# Wormhole Developer Documentation (LLMS Format)
This file contains documentation for Wormhole (https://wormhole.com). A cross-chain messaging protocol used to move data and assets between blockchains.
It is intended for use with large language models (LLMs) to support developers working with Wormhole. The content includes selected pages from the official docs, organized by product category and section.
This file includes documentation for the product: Queries
## AI Prompt Template
You are an AI developer assistant for Wormhole (https://wormhole.com). Your task is to assist developers in understanding and using the product described in this file.
- Provide accurate answers based on the included documentation.
- Do not assume undocumented features, behaviors, or APIs.
- If unsure, respond with “Not specified in the documentation.
## List of doc pages:
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/overview.md [type: overview]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/get-started.md [type: get-started]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/reference/supported-methods.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/reference/supported-networks.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/faqs.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/guides/use-queries.md [type: guide]
## Full content for each doc page
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/queries/overview.md
--- BEGIN CONTENT ---
---
title: Queries Overview
description: Learn how Wormhole Queries enable smart contracts to fetch real-time, Guardian-verified data across multiple blockchains.
categories: Queries
---
# Queries Overview
Queries provide on-demand access to Guardian-attested on-chain data. They allow smart contracts to fetch real-time, verifiable data from across the multichain ecosystem, such as prices, rates, and liquidity.
## Key Features
- **On-demand data access**: Fetch price feeds, interest rates, and other data in real-time.
- **Guardian attested**: All data is signed by [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} for trustless validation.
- **Cross-chain ready**: Request data on one chain, use it on another.
- **Smart contract integration**: Results are delivered as [Verified Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank}, readable by smart contracts.
- **Chain agnostic**: Works across supported EVM chains, Solana, Sui, and [more](/docs/products/queries/reference/supported-networks/){target=\_blank}.
## How It Works
A query request follows a simple but robust lifecycle. The off-chain service responsible for handling requests is called the CCQ Server (Cross-Chain Query Server), also referred to as the Query Server throughout this documentation.
1. An off-chain app sends a query to the CCQ Server via HTTPS.
2. The CCQ Server checks the request and shares it with [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank}.
3. [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} independently fetch the data, verify it, and sign the result.
4. Once enough Guardians (2/3 quorum) return matching results, the CCQ Server aggregates and sends the final response.
5. The off-chain app submits this result to a smart contract, which verifies the Guardian signatures and uses the data.
The CCQ Server is permissioned but trustless. Most queries resolve in under one second, and Guardians retry failed requests for up to one minute. Up to 255 queries can be batched together to optimize performance, supporting efficient multichain workflows.

## Use Cases
Queries enable a wide range of cross-chain applications. Below are common use cases and the Wormhole stack components you can use to build them.
- **Borrowing and Lending Across Chains (e.g., [Folks Finance](https://wormhole.com/case-studies/folks-finance){target=\_blank})**
- **[Queries](/docs/products/queries/get-started/){target=\_blank}**: Fetch rates and prices in real-time.
- **[Messaging](/docs/products/messaging/overview/){target=\_blank}**: Sync actions between chains.
- **[Native Token Transfers](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}**: Transfer collateral as native assets.
- **Cross-Chain Swaps and Liquidity Aggregation (e.g., [StellaSwap](https://app.stellaswap.com/exchange/swap){target=\_blank})**
- **[Queries](/docs/products/queries/get-started/){target=\_blank}**: Fetch live prices for optimal trade execution.
- **[Connect](/docs/products/connect/overview/){target=\_blank}**: Handle user-friendly asset transfers.
- **[Native Token Transfers](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}**: Moves native tokens.
- **Real-Time Price Feeds and Trading Strategies (e.g., [Infinex](https://wormhole.com/case-studies/infinex){target=\_blank})**
- **[Queries](/docs/products/queries/get-started/){target=\_blank}**: Fetch price feeds.
- **[Messaging](/docs/products/messaging/overview/){target=\_blank}**: Trigger trades.
- **Multichain Prediction Markets**
- **[Queries](/docs/products/queries/get-started/){target=\_blank}**: Fetch market data and odds.
- **[Settlement](/docs/products/settlement/overview/){target=\_blank}**: Automates token execution.
- **Oracle Networks (e.g., [Pyth](https://wormhole.com/case-studies/pyth){target=\_blank})**
- **[Queries](/docs/products/queries/get-started/){target=\_blank}**: Source data from chains.
- **[Messaging](/docs/products/messaging/overview/){target=\_blank}**: Ensures tamper-proof data relay across networks.
## Next Steps
Follow these steps to get started with Queries:
[timeline(wormhole-docs/.snippets/text/products/queries/queries-timeline.json)]
--- END CONTENT ---
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--- BEGIN CONTENT ---
---
title: Get Started with Queries
description: Follow this guide to run your first multichain, verifiable query with the Wormhole Queries SDK and Proxy, using eth_call to fetch token metadata.
categories: Queries
---
# Get Started with Queries
[Queries](/docs/products/queries/overview) lets you fetch on-chain data from supported blockchains using `eth_call`-style requests without submitting transactions or paying gas. The Guardian network signs the result, making it verifiable and suitable for use on-chain.
This guide walks you through requesting an API key, constructing your first query using the [Wormhole Query SDK](https://www.npmjs.com/package/@wormhole-foundation/wormhole-query-sdk){target=\_blank}, and decoding the result.
## Prerequisites
Before you begin, make sure you have the following:
- [Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm){target=\_blank}.
- A basic understanding of JavaScript or TypeScript.
- An RPC endpoint for a supported chain (e.g., Ethereum Sepolia).
- A Wormhole Queries API key.
## Request an API Key
Wormhole Queries is in closed beta, but you can start building today.
To interact with the system, you will use the Query Proxy. This hosted service receives your query, routes it to the appropriate chain, and returns a signed, verifiable response from the Guardian network. The Query Proxy allows you to fetch on-chain data without infrastructure overhead.
To request access, join the beta by filling out the [access form](https://forms.clickup.com/45049775/f/1aytxf-10244/JKYWRUQ70AUI99F32Q){target=\_blank}. Once approved, you will receive an API key via email.
## Construct a Query and Decode the Response
Using the Wormhole Query Proxy, you will write a lightweight script to query a token contract's `name()` on Ethereum Sepolia. The response is signed by the Guardian network and locally decoded for use in your application.
1. Create a new directory for your script and initialize a Node.js project:
```bash
mkdir queries
cd queries
npm init -y
```
2. Add the [Wormhole Query SDK](https://www.npmjs.com/package/@wormhole-foundation/wormhole-query-sdk){target=\_blank}, [Axios](https://www.npmjs.com/package/axios){target=\_blank}, [Web3](https://www.npmjs.com/package/web3){target=\_blank}, and helper tools:
```bash
npm install axios web3 @wormhole-foundation/wormhole-query-sdk
npm install -D tsx typescript
```
3. Add a new `query.ts` script where you will write and run your query logic:
```bash
touch query.ts
```
4. Paste the following script into `query.ts` to build and submit a query to the token contract's `name()` function on Ethereum Sepolia, then decode the Guardian-signed response:
```typescript
// Import the SDK types and helpers for making the query
import {
EthCallQueryRequest,
EthCallQueryResponse,
PerChainQueryRequest,
QueryRequest,
QueryResponse,
} from '@wormhole-foundation/wormhole-query-sdk';
import axios from 'axios';
import * as eth from 'web3';
// Define the endpoint and query parameters
const query_url = 'https://testnet.query.wormhole.com/v1/query';
const rpc = 'https://ethereum-sepolia.rpc.subquery.network/public';
const chain_id = 10002; // Sepolia (Wormhole chain ID)
const token = '0x1c7D4B196Cb0C7B01d743Fbc6116a902379C7238'; // USDC contract
const data = '0x06fdde03'; // function selector for `name()`
// Load your API key from environment variables
const apiKey = process.env.API_KEY;
if (!apiKey) throw new Error('API_KEY is not set in your environment');
(async () => {
// Fetch the latest block number (required to anchor the query)
const latestBlock = (
await axios.post(rpc, {
method: 'eth_getBlockByNumber',
params: ['latest', false],
id: 1,
jsonrpc: '2.0',
})
).data?.result?.number;
// Build the query targeting the token contract's name() function
const request = new QueryRequest(1, [
new PerChainQueryRequest(
chain_id,
new EthCallQueryRequest(latestBlock, [{ to: token, data: data }])
),
]);
const serialized = request.serialize();
// Send the query to the Wormhole Query Proxy
const response = await axios.post(
query_url,
{ bytes: Buffer.from(serialized).toString('hex') },
{ headers: { 'X-API-Key': apiKey } }
);
// Decode the response returned by the Guardian network
const queryResponse = QueryResponse.from(response.data.bytes);
const chainResponse = queryResponse.responses[0]
.response as EthCallQueryResponse;
const name = eth.eth.abi.decodeParameter('string', chainResponse.results[0]);
// Output the results
console.log('\n\nParsed chain response:');
console.log(chainResponse);
console.log('\nToken name:', name);
})();
```
5. Use your API key to execute the script:
```bash
API_KEY=INSERT_QUERIES_API_KEY npx tsx query.ts
```
The expected output should be similar to this:
## Next Steps
Now that you've successfully run your first verifiable query, you are ready to go deeper. Check out the following guides to build on what you've learned:
- **[Query Solana](https://github.com/wormhole-foundation/demo-queries-ts/blob/main/src/query_solana_stake_pool.ts){target=\_blank}**: Try fetching Solana stake pools to see how cross-chain queries apply beyond EVM.
- **[Use Queries](/docs/products/queries/guides/use-queries){target=\_blank}**: Take a deeper look at the complete Queries lifecycle.
- **Browse the [Supported Networks](/docs/products/queries/reference/supported-networks){target=\_blank}**: See where Queries are supported.
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--- BEGIN CONTENT ---
---
title: Queries Supported Methods
description: Retrieve multichain data via historical timestamp queries, finality confirmation queries, and Solana lookups.
categories: Queries
---
# Supported Methods
Wormhole Queries provides on-demand access to [Guardian](/docs/protocol/infrastructure/guardians/){target=\_blank}-attested on-chain data through a simple REST endpoint. It offers a faster, gasless alternative to traditional transaction-based data retrieval, removing the need for gas fees and transaction finality delays. Requests are handled off-chain and processed by the Guardians, delivering verified data efficiently and cost-effectively.
This page describes Wormhole Queries, their functionality, and available methods, aiming to assist new developers in utilizing the service.
## Supported Query Types
Wormhole currently supports five distinct query types, each designed for specific data retrieval tasks across various chains.
!!! note
For a more comprehensive technical description and further specifics on each query type, please consult the [white paper](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0013_ccq.md).
### eth_call
The [`eth_call`](https://ethereum.org/en/developers/docs/apis/json-rpc/#eth_call){target=\_blank} query type allows you to perform read-only calls to a smart contract on a specific block, identified by its number or hash. Some of eth_call's configurations include:
- **Batching**: Group multiple calls, even to different contracts, into a single query targeting the same block, which is processed as one batch RPC call to simplify on-chain verification.
- **Capacity**: Batch up to 255 individual in a single `eth_call` query.
- **Result data**: Provides the specified block's number, hash, timestamp, and the output from the contract call.
### eth_call_by_timestamp
The [`eth_call_by_timestamp`](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0013_ccq.md#timestamp-and-block-id-hints-in-eth_call_by_timestamp){target=\_blank} query is similar to a standard `eth_call` but targets a specific timestamp instead of a block ID. This is useful for retrieving on-chain data based on a precise point in time, especially for correlating information across different chains.
The query returns your target timestamp and the latest block details at or before your specified `target_time` immediately preceding the subsequent block.
### eth_call_with_finality
The [`eth_call_with_finality`](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0013_ccq.md#desired-finality-in-eth_call_with_finality){target=\_blank} query type functions like a standard `eth_call`, but with an added critical assurance: it will only return the query results once the specified block has reached a designated level of finality on its chain.
You can specify one of two finality levels for your query:
- **Finalized**: Indicates the highest level of assurance that a block is permanent and will not be altered or removed from the chain.
- **Safe**: Refers to a block considered highly unlikely to be reorganized, offering a substantial degree of confidence, though the network's consensus may not fully finalize it.
!!! note
If the target blockchain does not natively support or recognize the safe finality tag, requesting safe finality will be treated as a request for finalized finality instead.
### sol_account
The [`sol_account`](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0013_ccq.md#solana-queries){target=\_blank} query reads on-chain data for one or more specified accounts on the Solana blockchain. This functionality is similar to using Solana's native [`getMultipleAccounts`](https://solana.com/docs/rpc/http/getmultipleaccounts){target=\_blank} RPC method, enabling you to retrieve information for multiple accounts simultaneously
### sol_pda
The [`sol_pda`](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0013_ccq.md#solana_queries){target=\_blank} query reads data for one or more Solana [Program Derived Addresses](https://www.anchor-lang.com/docs/basics/pda){target=\_blank}. It streamlines the standard process of deriving a PDA and fetching its account data.
This is particularly useful for accessing multiple PDAs owned by a specific program or for verifying Solana PDA derivations on another blockchain, such as how associated token accounts are all derived from the [Associated Token Account Program](https://www.solana-program.com/docs/associated-token-account){target=\_blank}.
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--- BEGIN CONTENT ---
---
title: Queries Supported Networks
description: Reference table of chains supported by Wormhole Queries, including method support, finality, and expected historical data availability.
categories: Queries
---
# Supported Networks
This page provides a quick reference for chains supported by Wormhole Queries, including each chain's Wormhole chain ID and the level of support for key methods: [`eth_call`](/docs/products/queries/reference/supported-methods/#eth_call){target=\_blank}, [`eth_call_by_timestamp`](/docs/products/queries/reference/supported-methods/#eth_call_by_timestamp){target=\_blank}, and [`eth_call_with_finality`](/docs/products/queries/reference/supported-methods/#eth_call_with_finality){target=\_blank}.
The **Expected History** column shows how much recent state data is typically available for querying, though this can vary depending on the chain and the configuration of each Guardian node.
The support shown in the table reflects what has been confirmed through testing. However, query success ultimately depends on whether the underlying call can be executed on each Guardian’s RPC node.
For example, many chains use a fork of [Geth](https://github.com/ethereum/go-ethereum){target=\_blank}, which by default retains 128 blocks of state in memory (unless archive mode is enabled). On Ethereum mainnet, this covers around 25 minutes of history—but on faster chains like Optimism, it may span only about three minutes. While Guardian nodes are expected to have access to recent state, there are currently no guarantees on how far back historical data is available.
## Mainnet
| Chain | Wormhole Chain ID | eth_call | eth_call_by_timestamp | eth_call_with_finality | Expected History |
|:-------------:|:-----------------:|:--------:|:---------------------:|:----------------------:|:----------------:|
| Ethereum | 2 | ✅ | ✅ | ✅ | 128 blocks |
| BSC | 4 | ✅ | ✅ | ✅ | 128 blocks |
| Polygon | 5 | ✅ | ✅ | ✅ | 128 blocks |
| Avalanche | 6 | ✅ | ✅ | ✅ | 32 blocks |
| Oasis Emerald | 7 | ✅ | ✅ | ✅ | archive |
| Fantom | 10 | ✅ | ✅ | ✅ | 16 blocks |
| Karura | 11 | ✅ | ✅ | ✅ | archive |
| Acala | 12 | ✅ | ✅ | ✅ | archive |
| Kaia | 13 | ✅ | ✅ | ✅ | 128 blocks |
| Celo | 14 | ✅ | ℹ️ | ✅ | 128 blocks |
| Moonbeam | 16 | ✅ | ℹ️ | ✅ | 256 blocks |
| Arbitrum One | 23 | ✅ | ✅ | ✅ | ~6742 blocks |
| Optimism | 24 | ✅ | ✅ | ❌ | 128 blocks |
| Base | 30 | ✅ | ✅ | ✅ | archive |
ℹ️`EthCallByTimestamp` arguments for `targetBlock` and `followingBlock` are currently required for requests to be successful on these chains.
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--- BEGIN CONTENT ---
---
title: Queries FAQs
description: Wormhole Queries FAQ covering available libraries, query examples, response formats, and details about running query proxy servers.
categories: Queries
---
# Queries FAQs
## What is Queries?
Queries is Wormhole's on-demand, Guardian-attested data service. It lets you fetch real-time, verifiable on-chain data via a simple REST endpoint and use the signed result on-chain without sending a transaction or paying gas. You can request data on one chain and use the verified result on another. For a quick video summary, watch the [Queries speed round](https://www.youtube.com/watch?v=q-s8j7GAlfQ){target=\_blank}.
## What libraries are available to handle queries?
- The [Query TypeScript SDK](https://www.npmjs.com/package/@wormhole-foundation/wormhole-query-sdk){target=\_blank} can be used to create query requests, mock query responses for testing, and parse query responses. The SDK also includes utilities for posting query responses.
- The [Solidity `QueryResponseLib` library](https://github.com/wormhole-foundation/wormhole-solidity-sdk/blob/main/src/libraries/QueryResponse.sol){target=\_blank} can be used to parse and verify query responses on EVM chains. See the [Solana Stake Pool](https://github.com/wormholelabs-xyz/example-queries-solana-stake-pool){target=\_blank} repository as an example use case.
- [`QueryRequestBuilder.sol`](https://github.com/wormhole-foundation/wormhole-solidity-sdk/blob/main/src/testing/QueryRequestBuilder.sol){target=\_blank} can be used for mocking query requests and responses in Forge tests.
- The [Go query package](https://github.com/wormhole-foundation/wormhole/tree/main/node/pkg/query){target=\_blank} can also be used to create query requests and parse query responses.
!!! note
A Rust SDK for Solana is being actively investigated by the Wormhole contributors. See the [Solana Queries Verification](https://github.com/wormholelabs-xyz/example-queries-solana-verify){target=\_blank} repository as a proof of concept.
## Are there any query examples?
Certainly. You can find a complete guide on the [Use Queries page](/docs/products/queries/guides/use-queries/){target=\_blank}. Additionally, you can find full code examples in the following repositories:
- [Basic Example Query Demo](https://github.com/wormholelabs-xyz/example-queries-demo/){target=\_blank}
- [Solana Stake Pool Example Query](https://github.com/wormholelabs-xyz/example-queries-solana-stake-pool){target=\_blank}
- [Solana Program Derived Address (PDA) / Token Account Balance Example Query](https://github.com/wormholelabs-xyz/example-queries-solana-pda){target=\_blank}
- [Solana Queries Verification Example](https://github.com/wormholelabs-xyz/example-queries-solana-verify){target=\_blank}
## What is the format of the response signature?
The Guardian node calculates an ECDSA signature using [`Sign` function of the crypto package](https://pkg.go.dev/github.com/ethereum/go-ethereum@v1.10.21/crypto#Sign){target=\_blank} where the digest hash is:
```keccak256("query_response_0000000000000000000|"+keccak256(responseBytes))```
See the [Guardian Key Usage](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0009_guardian_signer.md){target=\_blank} white paper for more background. Once this signature is created, the Guardian's index in the Guardian set is appended to the end.
!!! note
If you are used to `ecrecover` you will notice that the `v` byte is `0` or `1` as opposed to `27` or `28`. The `signaturesToEvmStruct` method in the [Query TypeScript SDK](https://www.npmjs.com/package/@wormhole-foundation/wormhole-query-sdk){target=\_blank} accounts for this as well as structuring the signatures into an `IWormhole.SignatureStruct[]`.
## Can anyone run a query proxy server?
Permissions for Query Proxy are managed by the Guardians. The Guardian nodes are configured to only listen to a set of allow-listed proxies. However, it is possible that this restriction may be lifted in the future and/or more proxies could be added.
It is also important to note that the proxies don't impact the verifiability of the request or result, i.e., their role in the process is trustless.
## What Does Queries Offer over an RPC Service
Wormhole Queries provides on-demand, attested, on-chain, verifiable RPC results. Each Guardian independently executes the specified query and returns the result and their signature. The proxy handles aggregating the results and signatures, giving you a single result (all within one REST call) with a quorum of signatures suitable for on-chain submission, parsing, and verification using one of our examples or SDKs.
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--- BEGIN CONTENT ---
---
title: Use Queries
description: Explore a simple demo of interacting with Wormhole Queries using an eth_call request to query the supply of wETH on Ethereum using a Wormhole query.
categories: Queries
---
# Use Queries
You can visit the [Example Queries Demo](https://wormholelabs-xyz.github.io/example-queries-demo/){target=\_blank} to view an interactive example of an application interacting with the [Query Demo](https://github.com/wormholelabs-xyz/example-queries-demo/blob/main/src/QueryDemo.sol){target=\_blank} contract.
This guide covers using a simple `eth_call` request to get the total supply of WETH on Ethereum.
## Construct a Query {: #construct-a-query}
You can use the [Wormhole Query SDK](https://www.npmjs.com/package/@wormhole-foundation/wormhole-query-sdk){target=\_blank} to construct a query. You will also need an RPC endpoint from the provider of your choice. This example uses [Axios](https://www.npmjs.com/package/axios){target=\_blank} for RPC requests. Ensure that you also have [TypeScript](https://www.typescriptlang.org/download/){target=\_blank} installed.
```jsx
npm i @wormhole-foundation/wormhole-query-sdk axios
```
In order to make an `EthCallQueryRequest`, you need a specific block number or hash as well as the call data to request.
You can request the latest block from a public node using `eth_getBlockByNumber`.
```jsx
await axios.post(rpc, {
method: 'eth_getBlockByNumber',
params: ['latest', false],
id: 1,
jsonrpc: '2.0',
})
).data?.result?.number;
```
Then construct the call data.
```jsx
to: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2', // WETH
data: '0x18160ddd', // web3.eth.abi.encodeFunctionSignature("totalSupply()")
};
```
Finally, put it all together in a `QueryRequest`.
```jsx
const request = new QueryRequest(
0, // Nonce
[
new PerChainQueryRequest(
2, // Ethereum Wormhole Chain ID
new EthCallQueryRequest(latestBlock, [callData])
),
]
);
```
This request consists of one `PerChainQueryRequest`, which is an `EthCallQueryRequest` to Ethereum. You can use `console.log` to print the JSON object and review the structure.
```jsx
// {
// "nonce": 0,
// "requests": [
// {
// "chainId": 2,
// "query": {
// "callData": [
// {
// "to": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
// "data": "0x18160ddd"
// }
// ],
// "blockTag": "0x11e9068"
// }
// }
// ],
// "version": 1
// }
```
## Mock a Query
For easier testing, the Query SDK provides a `QueryProxyMock` method. This method will perform the request and sign the result with the [Devnet](https://github.com/wormhole-foundation/wormhole/blob/main/DEVELOP.md){target=\_blank} Guardian key. The `mock` call returns the same format as the Query Proxy.
```jsx
const mockData = await mock.mock(request);
console.log(mockData);
// {
// signatures: ['...'],
// bytes: '...'
// }
```
This response is suited for on-chain use, but the SDK also includes a parser to make the results readable via the client.
```jsx
const mockQueryResult = (
mockQueryResponse.responses[0].response as EthCallQueryResponse
).results[0];
console.log(
`Mock Query Result: ${mockQueryResult} (${BigInt(mockQueryResult)})`
);
// Mock Query Result:
// 0x000000000000000000000000000000000000000000029fd09d4d81addb3ccfee
// (3172556167631284394053614)
```
Testing this all together might look like the following:
```jsx
import {
EthCallData,
EthCallQueryRequest,
EthCallQueryResponse,
PerChainQueryRequest,
QueryProxyMock,
QueryRequest,
QueryResponse,
} from '@wormhole-foundation/wormhole-query-sdk';
import axios from 'axios';
const rpc = 'https://ethereum.publicnode.com';
const callData: EthCallData = {
to: '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2', // WETH
data: '0x18160ddd', // web3.eth.abi.encodeFunctionSignature("totalSupply()")
};
(async () => {
const latestBlock: string = (
await axios.post(rpc, {
method: 'eth_getBlockByNumber',
params: ['latest', false],
id: 1,
jsonrpc: '2.0',
})
).data?.result?.number;
if (!latestBlock) {
console.error(`❌ Invalid block returned`);
return;
}
console.log('Latest Block: ', latestBlock, `(${BigInt(latestBlock)})`);
const targetResponse = await axios.post(rpc, {
method: 'eth_call',
params: [callData, latestBlock],
id: 1,
jsonrpc: '2.0',
});
// console.log(finalizedResponse.data);
if (targetResponse.data.error) {
console.error(`❌ ${targetResponse.data.error.message}`);
}
const targetResult = targetResponse.data?.result;
console.log('Target Result: ', targetResult, `(${BigInt(targetResult)})`);
// Form the query request
const request = new QueryRequest(
0, // Nonce
[
new PerChainQueryRequest(
2, // Ethereum Wormhole Chain ID
new EthCallQueryRequest(latestBlock, [callData])
),
]
);
console.log(JSON.stringify(request, undefined, 2));
const mock = new QueryProxyMock({ 2: rpc });
const mockData = await mock.mock(request);
console.log(mockData);
const mockQueryResponse = QueryResponse.from(mockData.bytes);
const mockQueryResult = (
mockQueryResponse.responses[0].response as EthCallQueryResponse
).results[0];
console.log(
`Mock Query Result: ${mockQueryResult} (${BigInt(mockQueryResult)})`
);
})();
```
### Fork Testing
It is common to test against a local fork of Mainnet with something like
```jsx
anvil --fork-url https://ethereum.publicnode.com
```
In order for mock requests to verify against the Mainnet Core Contract, you need to replace the current Guardian set with the single Devnet key used by the mock.
Here's an example for Ethereum Mainnet, where the `-a` parameter is the [Core Contract address](/docs/products/reference/contract-addresses/#core-contracts){target=\_blank} on that chain.
```jsx
npx @wormhole-foundation/wormhole-cli evm hijack -a 0x98f3c9e6E3fAce36bAAd05FE09d375Ef1464288B -g 0xbeFA429d57cD18b7F8A4d91A2da9AB4AF05d0FBe
```
If you are using `EthCallWithFinality`, you will need to mine additional blocks (32 if using [Anvil](https://getfoundry.sh/anvil/overview#anvil){target=\_blank}) after the latest transaction for it to become finalized. Anvil supports [auto-mining](https://book.getfoundry.sh/reference/anvil/#mining-modes){target=\_blank} with the `-b` flag if you want to test code that waits naturally for the chain to advance. For integration tests, you may want to simply `anvil_mine` with `0x20`.
## Make a Query Request
The standardized means of making a `QueryRequest` with an API key is as follows:
```jsx
const serialized = request.serialize();
const proxyResponse =
(await axios.post) <
QueryProxyQueryResponse >
(QUERY_URL,
{
bytes: Buffer.from(serialized).toString("hex"),
},
{ headers: { "X-API-Key": YOUR_API_KEY } });
```
Remember to always take steps to protect your sensitive API keys, such as defining them in `.env` files and including such files in your `.gitignore`.
A Testnet Query Proxy is available at `https://testnet.query.wormhole.com/v1/query`
A Mainnet Query Proxy is available at `https://query.wormhole.com/v1/query`
## Verify a Query Response On-Chain
A [`QueryResponseLib` library](https://github.com/wormhole-foundation/wormhole-solidity-sdk/blob/main/src/libraries/QueryResponse.sol){target=\_blank} is provided to assist with verifying query responses. You can begin by installing the [Wormhole Solidity SDK](https://github.com/wormhole-foundation/wormhole-solidity-sdk){target=\_blank} with the following command:
```bash
forge install wormhole-foundation/wormhole-solidity-sdk
```
Broadly, using a query response on-chain comes down to three main steps:
1. Parse and verify the query response.
2. The `parseAndVerifyQueryResponse` handles verifying the Guardian signatures against the current Guardian set stored in the Core bridge contract.
3. Validate the request details. This may be different for every integrator depending on their use case, but generally checks the following:
- Is the request against the expected chain?
- Is the request of the expected type? The `parseEthCall` helpers perform this check when parsing.
- Is the resulting block number and time expected? Some consumers might require that a block number be higher than the last, or the block time be within the last 5 minutes. `validateBlockNum` and `validateBlockTime` can help with the checks.
- Is the request for the expected contract and function signature? The `validateMultipleEthCallData` can help with non-parameter-dependent cases.
- Is the result of the expected length for the expected result type?
4. Run `abi.decode` on the result.
See the [QueryDemo](https://github.com/wormholelabs-xyz/example-queries-demo/blob/main/src/QueryDemo.sol){target=\_blank} contract for an example and read the docstrings of the preceding methods for detailed usage instructions.
??? code "View the complete `QueryDemo`"
```solidity
// contracts/query/QueryDemo.sol
// SPDX-License-Identifier: Apache 2
pragma solidity ^0.8.0;
import "wormhole-solidity-sdk/libraries/BytesParsing.sol";
import "wormhole-solidity-sdk/interfaces/IWormhole.sol";
import "wormhole-solidity-sdk/QueryResponse.sol";
error InvalidOwner();
// @dev for the onlyOwner modifier
error InvalidCaller();
error InvalidCalldata();
error InvalidForeignChainID();
error ObsoleteUpdate();
error StaleUpdate();
error UnexpectedResultLength();
error UnexpectedResultMismatch();
/// @dev QueryDemo is an example of using the QueryResponse library to parse and verify Cross Chain Query (CCQ) responses.
contract QueryDemo is QueryResponse {
using BytesParsing for bytes;
struct ChainEntry {
uint16 chainID;
address contractAddress;
uint256 counter;
uint256 blockNum;
uint256 blockTime;
}
address private immutable owner;
uint16 private immutable myChainID;
mapping(uint16 => ChainEntry) private counters;
uint16[] private foreignChainIDs;
bytes4 public GetMyCounter = bytes4(hex"916d5743");
constructor(address _owner, address _wormhole, uint16 _myChainID) QueryResponse(_wormhole) {
if (_owner == address(0)) {
revert InvalidOwner();
}
owner = _owner;
myChainID = _myChainID;
counters[_myChainID] = ChainEntry(_myChainID, address(this), 0, 0, 0);
}
// updateRegistration should be used to add the other chains and to set / update contract addresses.
function updateRegistration(uint16 _chainID, address _contractAddress) public onlyOwner {
if (counters[_chainID].chainID == 0) {
foreignChainIDs.push(_chainID);
counters[_chainID].chainID = _chainID;
}
counters[_chainID].contractAddress = _contractAddress;
}
// getMyCounter (call signature 916d5743) returns the counter value for this chain. It is meant to be used in a cross chain query.
function getMyCounter() public view returns (uint256) {
return counters[myChainID].counter;
}
// getState() returns this chain's view of all the counters. It is meant to be used in the front end.
function getState() public view returns (ChainEntry[] memory) {
ChainEntry[] memory ret = new ChainEntry[](foreignChainIDs.length + 1);
ret[0] = counters[myChainID];
uint256 length = foreignChainIDs.length;
for (uint256 i = 0; i < length;) {
ret[i + 1] = counters[foreignChainIDs[i]];
unchecked {
++i;
}
}
return ret;
}
// @notice Takes the cross chain query response for the other counters, stores the results for the other chains, and updates the counter for this chain.
function updateCounters(bytes memory response, IWormhole.Signature[] memory signatures) public {
ParsedQueryResponse memory r = parseAndVerifyQueryResponse(response, signatures);
uint256 numResponses = r.responses.length;
if (numResponses != foreignChainIDs.length) {
revert UnexpectedResultLength();
}
for (uint256 i = 0; i < numResponses;) {
// Create a storage pointer for frequently read and updated data stored on the blockchain
ChainEntry storage chainEntry = counters[r.responses[i].chainId];
if (chainEntry.chainID != foreignChainIDs[i]) {
revert InvalidForeignChainID();
}
EthCallQueryResponse memory eqr = parseEthCallQueryResponse(r.responses[i]);
// Validate that update is not obsolete
validateBlockNum(eqr.blockNum, chainEntry.blockNum);
// Validate that update is not stale
validateBlockTime(eqr.blockTime, block.timestamp - 300);
if (eqr.result.length != 1) {
revert UnexpectedResultMismatch();
}
// Validate addresses and function signatures
address[] memory validAddresses = new address[](1);
bytes4[] memory validFunctionSignatures = new bytes4[](1);
validAddresses[0] = chainEntry.contractAddress;
validFunctionSignatures[0] = GetMyCounter;
validateMultipleEthCallData(eqr.result, validAddresses, validFunctionSignatures);
require(eqr.result[0].result.length == 32, "result is not a uint256");
chainEntry.blockNum = eqr.blockNum;
chainEntry.blockTime = eqr.blockTime / 1_000_000;
chainEntry.counter = abi.decode(eqr.result[0].result, (uint256));
unchecked {
++i;
}
}
counters[myChainID].blockNum = block.number;
counters[myChainID].blockTime = block.timestamp;
counters[myChainID].counter += 1;
}
modifier onlyOwner() {
if (owner != msg.sender) {
revert InvalidOwner();
}
_;
}
}
```
## Submit a Query Response On-Chain
The `QueryProxyQueryResponse` result requires a slight tweak when submitting to the contract to match the format of `function parseAndVerifyQueryResponse(bytes memory response, IWormhole.Signature[] memory signatures)`. A helper function, `signaturesToEvmStruct`, is provided in the SDK for this.
This example submits the transaction to the demo contract:
```jsx
const tx = await contract.updateCounters(
`0x${response.data.bytes}`,
signaturesToEvmStruct(response.data.signatures)
);
```
--- END CONTENT ---
## Shared Concepts from basics
The following section contains foundational documentation shared across all Wormhole products. It describes the architecture and messaging infrastructure that serve as the backbone for all integrations built with Wormhole. This context is provided to help understand how the system works under the hood, but responses should stay focused on the specific product unless the user explicitly asks about the general architecture.
---
## List of Shared Concept Pages:
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/overview.md [type: overview]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/overview.md [type: overview]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/get-started.md [type: get-started]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/glossary.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/concepts/solana-shim.md [type: concept]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/core-contracts.md [type: guide]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/solana-shims/sol-emission.md [type: guide]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/solana-shims/sol-verification.md [type: guide]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/wormhole-relayers.md [type: guide]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/cross-chain-contracts.md [type: tutorial]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/cross-chain-token-contracts.md [type: tutorial]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/replace-signatures.md [type: tutorial]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/architecture.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/ecosystem.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/core-contracts.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/guardians.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/relayer.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/spy.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/vaas.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/introduction.md [type: other]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/security.md [type: other]
## Full content for shared concepts:
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/overview.md
--- BEGIN CONTENT ---
---
title: Messaging Overview
description: With Wormhole Messaging, you can enable secure, multichain communication, build multichain apps, sync data, and coordinate actions across blockchains.
categories: Basics
---
# Messaging Overview
Wormhole Messaging is the core protocol of the Wormhole ecosystem—a generic, multichain message-passing layer that enables secure, fast communication between blockchains. It solves the critical problem of blockchain isolation by allowing data and assets to move freely across networks, empowering developers to build true multichain applications.
## Key Features
- **Multichain messaging**: Send arbitrary data between blockchains, enabling xDapps, governance actions, or coordination across ecosystems.
- **Decentralized validation**: A network of independent [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} observes and signs multichain messages, producing [Verifiable Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank} that ensure integrity.
- **Composable architecture**: Works with smart contracts, token bridges, or decentralized applications, providing a flexible foundation for multichain use cases.
## How It Works
The messaging flow consists of several core components:
1. **Source chain (emitter contract)**: A contract emits a message by calling the Wormhole [Core Contract](/docs/protocol/infrastructure/core-contracts/){target=\_blank} on the source chain.
2. **Guardian Network**: [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} observe the message, validate it, and generate a signed [VAA](/docs/protocol/infrastructure/vaas/){target=\_blank}.
3. **Relayers**: Off-chain or on-chain [relayers](/docs/protocol/infrastructure/relayer/){target=\_blank} transport the VAA to the destination chain.
4. **Target chain (recipient contract)**: The [Core Contract](/docs/protocol/infrastructure/core-contracts/){target=\_blank} on the destination chain verifies the VAA and triggers the specified application logic.

## Use Cases
Wormhole Messaging enables a wide range of multichain applications. Below are common use cases and the Wormhole stack components you can use to build them.
- **Borrowing and Lending Across Chains (e.g., [Folks Finance](https://wormhole.com/case-studies/folks-finance){target=\_blank})**
- **[Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Coordinate actions across chains.
- **[Native Token Transfers](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}**: Transfer collateral as native assets.
- **[Queries](/docs/products/queries/overview/){target=\_blank}**: Fetch rates and prices in real-time.
- **Oracle Networks (e.g., [Pyth](https://wormhole.com/case-studies/pyth){target=\_blank})**
- **[Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Relay verified data.
- **[Queries](/docs/products/queries/overview/){target=\_blank}**: Aggregate multi-chain sources.
- **Gas Abstraction**
- **[Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Coordinate gas logic.
- **[Native Token Transfers](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}**: Handle native token swaps.
- **Bridging Intent Library**
- **[Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Dispatch and execute intents.
- **[Settlement](/docs/products/settlement/overview/){target=\_blank}**: Execute user-defined bridging intents.
- **Decentralized Social Platforms (e.g., [Chingari](https://chingari.io/){target=\_blank})**
- **[Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Facilitate decentralized interactions.
- **[Wrapped Token Transfers](/docs/products/token-transfers/wrapped-token-transfers/overview/){target=\_blank}**: Enable tokenized rewards.
## Next Steps
Follow these steps to work with Wormhole Messaging:
- **[Get Started with Messaging](/docs/products/messaging/get-started/){target=\_blank}**: Use the core protocol to publish a multichain message and return transaction info with VAA identifiers.
- **[Use Wormhole Relayers](/docs/products/messaging/guides/wormhole-relayers/){target=\_blank}**: Send and receive messages without off-chain infrastructure.
For lower-cost, efficient integration with Core Bridge on Solana, consider using shim programs:
- [**Solana Shims**](/docs/products/messaging/concepts/solana-shim/){target=\_blank} : Learn about the purpose and benefits of using shims on Solana.
- [**Emission Shim**](/docs/products/messaging/guides/solana-shims/sol-emission/){target=\_blank}: Emit messages without creating permanent accounts, reducing rent costs.
- [**Verification Shim**](/docs/products/messaging/guides/solana-shims/sol-verification/){target=\_blank}: Efficiently verify Wormhole VAAs without leaving rent-exempt accounts.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/overview.md
--- BEGIN CONTENT ---
---
title: Compare Wormhole's Cross-Chain Solutions
description: Compare Wormhole’s cross-chain solutions for bridging, native transfers, data queries, and governance to enable seamless blockchain interoperability.
categories: Transfer, Basics
---
# Products
Wormhole provides a comprehensive suite of cross-chain solutions, enabling seamless asset transfers, data retrieval, and governance across blockchain ecosystems.
Wormhole provides multiple options for asset transfers: Connect for a plug-and-play bridging UI, Native Token Transfers (NTT) for moving native assets without wrapped representations, and Wrapped Token Transfers (WTT) for a secure lock-and-mint mechanism.
Beyond transfers, Wormhole extends interoperability with tools for cross-chain data access, decentralized governance, and an intent-based protocol through Wormhole Settlement.
## Transfer Products
Wormhole offers different solutions for cross-chain asset transfer, each designed for various use cases and integration requirements.
- **[Native Token Transfers (NTT)](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}**: A mechanism to transfer native tokens cross-chain seamlessly without conversion to a wrapped asset. Best for projects that require maintaining token fungibility and native chain functionality across multiple networks.
- **[Wrapped Token Transfers (WTT)](/docs/products/token-transfers/wrapped-token-transfers/overview/){target=\_blank}**: A bridging solution that uses a lock and mint mechanism. Best for projects that need cross-chain liquidity using wrapped assets and the ability to send messages.
- **[Settlement](/docs/products/settlement/overview/){target=\_blank}**: Intent-based protocols enabling fast multichain transfers, optimized liquidity flows, and interoperability without relying on traditional bridging methods.
For a deeper dive into how token transfers work and the differences between NTT and WTT, see the [Token Transfers Overview](/docs/products/token-transfers/overview/){target=\_blank}.
Beyond asset transfers, Wormhole provides additional tools for cross-chain data and governance.
## Bridging UI
[**Connect**](/docs/products/connect/overview/){target=\_blank} is a pre-built bridging UI for cross-chain token transfers, requiring minimal setup. Best for projects seeking an easy-to-integrate UI for bridging without modifying contracts.
## Real-time Data
[**Queries**](/docs/products/queries/overview/){target=\_blank} is a data retrieval service to fetch on-chain data from multiple networks. Best for applications that need multichain analytics, reporting, and data aggregation.
## Multichain Governance
[**MultiGov**](/docs/products/multigov/overview/){target=\_blank} is a unified governance framework that manages multichain protocol governance through a single mechanism. Best for projects managing multichain governance and protocol updates.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/get-started.md
--- BEGIN CONTENT ---
---
title: Get Started with Messaging
description: Follow this guide to use Wormhole's core protocol to publish a multichain message and return transaction information with VAA identifiers.
categories: Basics, Typescript SDK
---
# Get Started with Messaging
Wormhole's core functionality allows you to send any data packet from one supported chain to another. This guide demonstrates how to publish your first simple, arbitrary data message from an EVM environment source chain using the Wormhole TypeScript SDK's core messaging capabilities.
## Prerequisites
Before you begin, ensure you have the following:
- [Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm){target=\_blank} installed.
- [TypeScript](https://www.typescriptlang.org/download/){target=\_blank} installed.
- [Ethers.js](https://docs.ethers.org/v6/getting-started/){target=\_blank} installed (this example uses version 6).
- A small amount of testnet tokens for gas fees. This example uses [Sepolia ETH](https://sepolia-faucet.pk910.de/){target=\_blank} but can be adapted for any supported network.
- A private key for signing blockchain transactions.
## Configure Your Messaging Environment
1. Create a directory and initialize a Node.js project:
```bash
mkdir core-message
cd core-message
npm init -y
```
2. Install TypeScript, tsx, Node.js type definitions, and Ethers.js:
```bash
npm install --save-dev tsx typescript @types/node ethers
```
3. Create a `tsconfig.json` file if you don't have one. You can generate a basic one using the following command:
```bash
npx tsc --init
```
Make sure your `tsconfig.json` includes the following settings:
```json
{
"compilerOptions": {
// es2020 or newer
"target": "es2020",
// Use esnext if you configured your package.json with type: "module"
"module": "commonjs",
"esModuleInterop": true,
"forceConsistentCasingInFileNames": true,
"strict": true,
"skipLibCheck": true,
"resolveJsonModule": true
}
}
```
4. Install the [TypeScript SDK](/docs/tools/typescript-sdk/get-started/){target=\_blank}:
```bash
npm install @wormhole-foundation/sdk
```
5. Create a new file named `main.ts`:
```bash
touch main.ts
```
## Construct and Publish Your Message
1. Open `main.ts` and update the code there as follows:
```ts title="main.ts"
import {
wormhole,
signSendWait,
toNative,
encoding,
type Chain,
type Network,
type NativeAddress,
type WormholeMessageId,
type UnsignedTransaction,
type TransactionId,
type WormholeCore,
type Signer as WormholeSdkSigner,
type ChainContext,
} from '@wormhole-foundation/sdk';
// Platform-specific modules
import EvmPlatformLoader from '@wormhole-foundation/sdk/evm';
import { getEvmSigner } from '@wormhole-foundation/sdk-evm';
import {
ethers,
Wallet,
JsonRpcProvider,
Signer as EthersSigner,
} from 'ethers';
/**
* The required value (SEPOLIA_PRIVATE_KEY) must
* be loaded securely beforehand, for example via a keystore, secrets
* manager, or environment variables (not recommended).
*/
const SEPOLIA_PRIVATE_KEY = SEPOLIA_PRIVATE_KEY!;
// Provide a private endpoint RPC URL for Sepolia, defaults to a public node
// if not set
const RPC_URL =
process.env.SEPOLIA_RPC_URL || 'https://ethereum-sepolia-rpc.publicnode.com';
async function main() {
// Initialize Wormhole SDK
const network = 'Testnet';
const wh = await wormhole(network, [EvmPlatformLoader]);
console.log('Wormhole SDK Initialized.');
// Get the EVM signer and provider
let ethersJsSigner: EthersSigner;
let ethersJsProvider: JsonRpcProvider;
try {
if (!SEPOLIA_PRIVATE_KEY) {
console.error('Please set the SEPOLIA_PRIVATE_KEY environment variable.');
process.exit(1);
}
ethersJsProvider = new JsonRpcProvider(RPC_URL);
const wallet = new Wallet(SEPOLIA_PRIVATE_KEY);
ethersJsSigner = wallet.connect(ethersJsProvider);
console.log(
`Ethers.js Signer obtained for address: ${await ethersJsSigner.getAddress()}`,
);
} catch (error) {
console.error('Failed to get Ethers.js signer and provider:', error);
process.exit(1);
}
// Define the source chain context
const sourceChainName: Chain = 'Sepolia';
const sourceChainContext = wh.getChain(sourceChainName) as ChainContext<
'Testnet',
'Sepolia',
'Evm'
>;
console.log(`Source chain context obtained for: ${sourceChainContext.chain}`);
// Get the Wormhole SDK signer, which is a wrapper around the Ethers.js
// signer using the Wormhole SDK's signing and transaction handling
// capabilities
let sdkSigner: WormholeSdkSigner;
try {
sdkSigner = await getEvmSigner(ethersJsProvider, ethersJsSigner);
console.log(
`Wormhole SDK Signer obtained for address: ${sdkSigner.address()}`,
);
} catch (error) {
console.error('Failed to get Wormhole SDK Signer:', error);
process.exit(1);
}
// Construct your message payload
const messageText = `HelloWormholeSDK-${Date.now()}`;
const payload: Uint8Array = encoding.bytes.encode(messageText);
console.log(`Message to send: "${messageText}"`);
// Define message parameters
const messageNonce = Math.floor(Math.random() * 1_000_000_000);
const consistencyLevel = 1;
try {
// Get the core protocol client
const coreProtocolClient: WormholeCore =
await sourceChainContext.getWormholeCore();
// Generate the unsigned transactions
const whSignerAddress: NativeAddress = toNative(
sdkSigner.chain(),
sdkSigner.address(),
);
console.log(
`Preparing to publish message from ${whSignerAddress.toString()} on ${
sourceChainContext.chain
}...`,
);
const unsignedTxs: AsyncGenerator> =
coreProtocolClient.publishMessage(
whSignerAddress,
payload,
messageNonce,
consistencyLevel,
);
// Sign and send the transactions
console.log(
'Signing and sending the message publication transaction(s)...',
);
const txIds: TransactionId[] = await signSendWait(
sourceChainContext,
unsignedTxs,
sdkSigner,
);
if (!txIds || txIds.length === 0) {
throw new Error('No transaction IDs were returned from signSendWait.');
}
const primaryTxIdObject = txIds[txIds.length - 1];
const primaryTxid = primaryTxIdObject.txid;
console.log(`Primary transaction ID for parsing: ${primaryTxid}`);
console.log(
`View on Sepolia Etherscan: https://sepolia.etherscan.io/tx/${primaryTxid}`,
);
console.log(
'\nWaiting a few seconds for transaction to propagate before parsing...',
);
await new Promise((resolve) => setTimeout(resolve, 8000));
// Retrieve VAA identifiers
console.log(
`Attempting to parse VAA identifiers from transaction: ${primaryTxid}...`,
);
const messageIds: WormholeMessageId[] =
await sourceChainContext.parseTransaction(primaryTxid);
if (messageIds && messageIds.length > 0) {
const wormholeMessageId = messageIds[0];
console.log('--- VAA Identifiers (WormholeMessageId) ---');
console.log(' Emitter Chain:', wormholeMessageId.chain);
console.log(' Emitter Address:', wormholeMessageId.emitter.toString());
console.log(' Sequence:', wormholeMessageId.sequence.toString());
console.log('-----------------------------------------');
} else {
console.error(
`Could not parse Wormhole message IDs from transaction ${primaryTxid}.`,
);
}
} catch (error) {
console.error(
'Error during message publishing or VAA identifier retrieval:',
error,
);
if (error instanceof Error && error.stack) {
console.error('Stack Trace:', error.stack);
}
}
}
main().catch((e) => {
console.error('Critical error in main function (outer catch):', e);
if (e instanceof Error && e.stack) {
console.error('Stack Trace:', e.stack);
}
process.exit(1);
});
```
This script initializes the SDK, defines values for the source chain, creates an EVM signer, constructs the message, uses the core protocol to generate, sign, and send the transaction, and returns the VAA identifiers upon successful publication of the message.
2. Run the script using the following command:
```bash
npx tsx main.ts
```
You will see terminal output similar to the following:
npx tsx main.tsWormhole SDK Initialized.Ethers.js Signer obtained for address: 0xCD8Bcd9A793a7381b3C66C763c3f463f70De4e12Source chain context obtained for: SepoliaWormhole SDK Signer obtained for address: 0xCD8Bcd9A793a7381b3C66C763c3f463f70De4e12Message to send: "HelloWormholeSDK-1748362375390"Preparing to publish message from 0xCD8Bcd9A793a7381b3C66C763c3f463f70De4e12 on Sepolia...Signing and sending the message publication transaction(s)...Primary Transaction ID for parsing: 0xeb34f35f91c72e4e5198509071d24fd25d8a979aa93e2f168de075e3568e1508View on Sepolia Etherscan: https://sepolia.etherscan.io/tx/0xeb34f35f91c72e4e5198509071d24fd25d8a979aa93e2f168de075e3568e1508Waiting a few seconds for transaction to propagate before parsing...Attempting to parse VAA identifiers from transaction:
0xeb34f35f91c72e4e5198509071d24fd25d8a979aa93e2f168de075e3568e1508...--- VAA Identifiers (WormholeMessageId) --- Emitter Chain: Sepolia Emitter Address: 0x000000000000000000000000cd8bcd9a793a7381b3c66c763c3f463f70de4e12 Sequence: 1-----------------------------------------
3. Make a note of the transaction ID and VAA identifier values. You can use the transaction ID to [view the transaction on Wormholescan](https://wormholescan.io/#/tx/0xeb34f35f91c72e4e5198509071d24fd25d8a979aa93e2f168de075e3568e1508?network=Testnet){target=\_blank}. The emitter chain, emitter address, and sequence values are used to retrieve and decode signed messages.
Congratulations! You've published your first multichain message using Wormhole's TypeScript SDK and core protocol functionality. Consider the following options to build upon what you've accomplished.
## Next Steps
- **[Get Started with WTT](/docs/products/token-transfers/wrapped-token-transfers/get-started/){target=\_blank}**: Follow this guide to start working with multichain token transfers using Wormhole Wrapped Token Transfers' lock and mint mechanism to send tokens across chains.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/glossary.md
--- BEGIN CONTENT ---
---
title: Glossary
description: Explore a comprehensive glossary of technical terms and key concepts used in the Wormhole network, covering Chain ID, Guardian, VAA, and more.
categories: Basics
---
# Glossary
This glossary is an index of technical term definitions for words commonly used in Wormhole documentation.
## Chain ID
Wormhole assigns a unique `u16` integer chain ID to each supported blockchain. These chain IDs are specific to Wormhole and may differ from those used by blockchains to identify their networks.
You can find each chain ID documented on the [Wormhole Chain IDs](/docs/products/reference/chain-ids/){target=\_blank} page.
## Consistency Level
The level of finality (consistency) a transaction should meet before being signed by a Guardian. See the [Wormhole Finality](/docs/products/reference/consistency-levels/){target=\_blank} reference page for details.
## Delivery Provider
A Delivery Provider monitors for Wormhole Relayer delivery requests and delivers those requests to the intended target chain as instructed.
## Emitter
The emitter contract makes the call to the Wormhole Core Contract. The published message includes the emitter contract address and, a sequence number for the message is tracked to provide a unique ID.
## Finality
The finality of a transaction depends on its blockchain properties. Once a transaction is considered final, you can assume the resulting state changes it caused won't be reverted.
## Guardian
A [Guardian](/docs/protocol/infrastructure/guardians/){target=\_blank} is one of the 19 parties running validators in the Guardian Network contributing to the VAA multisig.
## Guardian Network
Validators in their own P2P network who serve as Wormhole's oracle by observing activity on-chain and generating signed messages attesting to that activity.
## Guardian Set
The Guardian Set is a set of guardians responsible for validating a message emitted from the core contracts. Occasionally, the members of the set will change through a governance action.
## Heartbeat
Each Guardian will issue a `heartbeat` on a 15-second interval to signal that it is still running and convey details about its identity, uptime, version, and the status of the connected nodes.
You can view the heartbeats on the [Wormhole dashboard](https://wormhole-foundation.github.io/wormhole-dashboard/#/?endpoint=Mainnet){target=\_blank}.
## Observation
An Observation is a data structure describing a message emitted by the Core Contract and noticed by the Guardian node.
## Relayer
A relayer is any process that delivers VAAs to a destination.
## Sequence
A nonce, strictly increasing, which is tracked by the Wormhole Core Contract and unique to the emitter chain and address.
## Spy
A Spy is a daemon that eavesdrops on the messages passed between Guardians, typically to track VAAs as they get signed.
## VAA
[Verifiable Action Approvals](/docs/protocol/infrastructure/vaas/){target=\_blank} (VAAs) are the base data structure in the Wormhole ecosystem. They contain emitted messages along with information such as what contract emitted the message.
## Validator
A daemon configured to monitor a blockchain node and observe messages emitted by the Wormhole contracts.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/concepts/solana-shim.md
--- BEGIN CONTENT ---
---
title: Solana Shims
description: Understand how Wormhole uses shim programs on Solana to optimize message emission and VAA verification without modifying the Core Bridge.
categories: Basics
---
# Solana Shims
Wormhole shims on Solana are lightweight programs that enable cheaper and more flexible message emission and verification while preserving Guardian observation guarantees. They are designed for integrators who want to reduce Solana rent costs without sacrificing core protocol security or Guardian compatibility.
## The Core Bridge Account Problem
When you emit a message on Solana using the legacy [Wormhole core bridge](/docs/protocol/infrastructure/core-contracts/){target=\_blank}, it creates a new on-chain account, a Program Derived Address (PDA), for every message. Each of these accounts must hold enough SOL to be rent-exempt, locking up lamports that cannot be reclaimed since the core bridge does not allow these accounts to be closed. Over time, this results in two big problems:
- **Permanent On-Chain State**: Every message leaves behind a permanent account, increasing long-term storage needs on Solana.
- **Lost Lamports to Rent**: Integrators lose SOL for every message, as the lamports needed for rent exemption remain locked in the message accounts indefinitely.
Solana’s rent-exemption model isn't the fundamental limitation; the constraint lies in the legacy `post_message` function of the core bridge, which always creates a new, non-reclaimable account every time it’s called. Even after a message is consumed, these accounts can’t be closed or reused, resulting in unrecoverable rent costs.
Although the `post_message_unreliable` function allows for account reuse, it comes with strict tradeoffs. Once a message is overwritten, it can no longer be recovered, making it no longer observable by Guardians. It also locks you into the original account size, as the feature predates Solana’s account resizing.
Verification has similar costs. The `post_vaa` instruction creates additional temporary accounts for signatures and VAA data, which again require rent and aren’t automatically cleaned up. Over time, these add to both storage bloat and unrecoverable SOL.
This design ensures reliability, as message data is always available on-chain for Guardians to observe. However, it comes at a cost in both storage and lost SOL. To address these issues, Wormhole introduces Solana shims, which fundamentally change the cost model for emission and verification.
## What Are the Solana Shims?
To address the limitations of the core bridge, Wormhole deploys two specialized Solana programs called shims:
- **[Post Message Shim (`EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX`)](https://explorer.solana.com/address/EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX){target=\_blank}**: Emits Wormhole messages efficiently, without creating new message accounts for each emission, reducing rent costs.
- **[Verify VAA Shim (`EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at`)](https://explorer.solana.com/address/EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at){target=\_blank}**: Verifies VAAs on-chain without leaving permanent accounts.
Both act as lightweight wrappers around the existing core bridge. There are two different options, depending on whether you are emitting messages or verifying VAAs:
### Emission Shim
The [Emission Shim](/docs/products/messaging/guides/solana-shims/sol-emission/){target=\_blank} is a Solana program deployed at [`EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX`](https://explorer.solana.com/address/EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX){target=\_blank}. It wraps the core bridge’s `post_message_unreliable` instruction and emits message data as a log event instead of storing it in a rent-exempt message account. This eliminates rent costs and prevents long-term state bloat. Guardians are configured to observe this canonical shim, allowing integrators to send messages through it without additional setup.
It works by calling the [`post_message`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/idls/wormhole_post_message_shim.json){target=_blank} instruction on the Post Message Shim program. This emits the Wormhole message as a log event instead of creating a rent-exempt message account.
The shim differs from the standard `post_message` approach in two key ways. First, it utilizes a Program Derived Address (PDA) per emitter for message accounts, eliminating the need to generate a new key pair for each emission. Second, instead of writing the message into a persistent, rent-exempt account, it emits the data via an Anchor CPI event, which Guardians can observe directly. This design reduces rent costs and prevents unused accounts from being left behind.
The shim works through a few main components:
- **Shim Program**: Provides a `post_message` instruction modeled on the core bridge’s `post_message_unreliable`.
- **Sequence Handling**: The core bridge continues to manage sequence numbers. It reads the sequence number from the core bridge and emits it in a [CPI event](https://www.anchor-lang.com/docs/basics/cpi){target=\_blank}, along with the timestamp.
- **Message Account**: Calls `post_message_unreliable` on the core bridge, writing an empty payload, so no unique message is stored on-chain.
- **Guardian Role**: Guardians reconstruct the message from instruction data and the emitted event, not from a persistent account.
```mermaid
graph LR
A[Integrator Program]
B[Emission Shim]
C[Core Bridge]
D[Guardians]
A -- call post_message --> B
B -- emits event & calls core --> C
C -- instruction data & event --> D
```
The emission fee is still paid, and the core bridge continues to manage sequence numbers as before. The difference is that instead of creating a new message account for each emission, the shim emits a CPI event with the message data. All the information Guardians need is captured in the transaction logs, without leaving behind permanent accounts.
### Verification Shim
The [Verification Shim](/docs/products/messaging/guides/solana-shims/sol-verification/){target=\_blank} is a Solana program deployed at [`EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at`](https://explorer.solana.com/address/EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at){target=\_blank}. It provides a [`verify_hash`](https://github.com/wormhole-foundation/wormhole/blob/4656bd4a72cb99f4e94a771a802856c9451af844/svm/wormhole-core-shims/programs/verify-vaa/src/lib.rs#L195){target=\_blank} instruction that checks Guardian signatures against the active Guardian set for a VAA's digest. It ensures quorum, validates each signature in order, recovers the public keys, and matches them against the Guardian set. If all checks pass, the VAA is verified without creating persistent rent-exempt accounts. This replaces using the core bridge’s `post_vaa`. Integrators can call the canonical shim, but existing programs may need to be modified to adopt this approach.
It works by first calling the [`post_signatures`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/idls/wormhole_verify_vaa_shim.json#L43){target=_blank} on the Verification Shim to store Guardian signatures in a temporary account. Then, from within your program, call [`verify_hash`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/programs/verify-vaa/README.md#verify-hash-technical-details){target=_blank} to check the VAA’s digest against Guardian signatures. In the same transaction, close the signatures account with [`close_signatures`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/idls/wormhole_verify_vaa_shim.json#L11){target=\_blank} to reclaim rent.
Instead of the core bridge instructions, such as `verify_signatures` and `post_vaa`, the verification shim provides its own flow using `post_signatures`, `verify_hash`, and `close_signatures`. The flow is a simpler sequence that avoids leaving permanent accounts on-chain:
1. Call `post_signatures`: Creates (or appends to) a temporary `GuardianSignatures` account that stores the collected Guardian signatures. This account is owned and managed by the verification shim.
2. Call `verify_hash`: Verifies the digest of the VAA against the active Guardian set and checks quorum by recovering and validating each Guardian signature. If verification succeeds, your program can continue its logic.
3. Call `close_signatures`: Immediately closes the `GuardianSignatures` account to reclaim the lamports paid for its creation.
```mermaid
graph LR
A[post_signatures] --> B[verify_hash]
B --> C[Process Logic]
C --> D[close_signatures]
```
This flow ensures verification is both rent-efficient and secure, no permanent accounts remain, and Guardians still enforce quorum and integrity guarantees.
## Guardian Observation Methods
| | Legacy Model | Shim Model |
|----------------------|------------------------|--------------------------|
| Message Storage | On-chain account | Transaction logs (CPI) |
| Data Permanence | Permanent | Until RPC history pruned |
| Guardian Observation | Reads account data | Reads transaction logs |
| Cost | High (rent + compute) | Low (compute only) |
| Closing Accounts | Not possible | Not needed |
With shims, the message’s existence depends on the transaction log, so cost drops, but indefinite on-chain visibility is no longer guaranteed. Sequence tracking remains the same as the legacy model, so integrators can switch between the two without disrupting sequence numbers.
## Transaction Costs
Solana charges for two main resources when processing transactions: compute units (for execution) and rent (for storing data on-chain). Understanding how each contributes to the overall cost is key to seeing why shims are cheaper.
- **Compute Units (CU)**: Solana measures CPU resource usage per transaction as “compute units”. Each transaction has a CU limit (usually ~200,000 — which can be increased for a fee).
- **Rent**: One-time cost in SOL to keep an account on-chain. Most of the core bridge’s cost comes from rent, not CUs.
Even though the shim uses slightly more compute (extra logic for logging), it avoids account creation entirely. Since rent is the most significant cost, the total emission cost drops.
## Safety, Tradeoffs & Limitations
Shims preserve the same security guarantees as the core bridge so that integrators can adopt shims without weakening protocol safety. The only difference is where data lives: instead of being stored permanently in message accounts, it is emitted in transaction logs or held temporarily until verification completes. Guardians are explicitly configured to observe shim output, ensuring messages and VAAs remain verifiable across the network.
The main tradeoff is durability. In the legacy model, messages and VAAs were always available on-chain for re-observation. With shims, message data persists only as long as transaction history is retained by RPC providers. This is sufficient for Guardian observation, but doesn’t provide indefinite public access to raw message data. Applications that rely on long-term on-chain storage may still prefer the legacy path, while most integrators benefit from the reduced cost and state bloat.
Finally, adopting shims may require some integration changes. For emission, developers should route messages through the Post Message Shim rather than directly through the core bridge. For verification, programs must update their logic to call `verify_hash` and manage temporary accounts in the same transaction. These are lightweight adjustments, but they are necessary to take full advantage of the cost savings.
## Next Steps
To put these concepts into practice, explore the dedicated guides for emission and verification on Solana:
- [Efficient Emission on Solana](/docs/products/messaging/guides/solana-shims/sol-emission/){target=\_blank}
- [Efficient Verification on Solana](/docs/products/messaging/guides/solana-shims/sol-verification/){target=\_blank}
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/core-contracts.md
--- BEGIN CONTENT ---
---
title: Get Started with Core Contracts
description: This guide walks through the key methods of the Core Contracts, providing you with the knowledge needed to integrate them into your cross-chain contracts
categories: Basics
---
# Get Started with Core Contracts
Wormhole's Core Contracts, deployed on each supported blockchain network, enable the fundamental operations of sending and receiving cross-chain messages.
While the implementation details of the Core Contracts varies by network, the core functionality remains consistent across chains. Each version of the Core Contract facilitates secure and reliable cross-chain communication, ensuring that developers can effectively publish and verify messages.
This guide will walk you through the variations and key methods of the Core Contracts, providing you with the knowledge needed to integrate them into your cross-chain contracts. To learn more about Core Contracts' features and how it works, please refer to the [Core Contracts](/docs/protocol/infrastructure/core-contracts/){target=\_blank} page in the Learn section.
## Prerequisites
To interact with the Wormhole Core Contract, you'll need the following:
- The [address of the Core Contract](/docs/products/reference/contract-addresses/#core-contracts){target=\_blank} on the chains you're deploying your contract on.
- The [Wormhole chain ID](/docs/products/reference/chain-ids/){target=\_blank} of the chains you're deploying your contract on.
- The [Wormhole Finality](/docs/products/reference/consistency-levels/){target=\_blank} (consistency) levels (required finality) for the chains you're deploying your contract on.
## How to Interact with Core Contracts
Before writing your own contracts, it's essential to understand the key functions and events of the Wormhole Core Contracts. The primary functionality revolves around:
- **Sending messages**: Submitting messages to the Wormhole network for cross-chain communication.
- **Receiving and verifying messages**: Validating messages received from other chains via the Wormhole network.
While the implementation details of the Core Contracts vary by network, the core functionality remains consistent across chains.
### Sending Messages
To send a message, regardless of the environment or chain, the Core Contract is invoked with a message argument from an [emitter](/docs/products/reference/glossary/#emitter){target=\_blank}. This emitter might be your contract or an existing application such as the [Wrapped Token Transfers (WTT)](/docs/products/token-transfers/wrapped-token-transfers/overview/){target=\_blank}.
=== "EVM"
The `IWormhole.sol` interface provides the `publishMessage` function, which can be used to publish a message directly to the Core Contract:
```solidity
function publishMessage(
uint32 nonce,
bytes memory payload,
uint8 consistencyLevel
) external payable returns (uint64 sequence);
```
??? interface "Parameters"
`nonce` ++"uint32"++
A free integer field that can be used however you like. Note that changing the `nonce` will result in a different digest.
---
`payload` ++"bytes memory"++
The content of the emitted message. Due to the constraints of individual blockchains, it may be capped to a certain maximum length.
---
`consistencyLevel` ++"uint8"++
A value that defines the required level of finality that must be reached before the Guardians will observe and attest to emitted events.
??? interface "Returns"
`sequence` ++"uint64"++
A unique number that increments for every message for a given emitter (and implicitly chain). This, combined with the emitter address and emitter chain ID, allows the VAA for this message to be queried from the [Wormholescan API](https://docs.wormholescan.io/){target=\_blank}.
??? interface "Example"
```solidity
IWormhole wormhole = IWormhole(wormholeAddr);
// Get the fee for publishing a message
uint256 wormholeFee = wormhole.messageFee();
// Check fee and send parameters
// Create the HelloWorldMessage struct
HelloWorldMessage memory parsedMessage = HelloWorldMessage({
payloadID: uint8(1),
message: helloWorldMessage
});
// Encode the HelloWorldMessage struct into bytes
bytes memory encodedMessage = encodeMessage(parsedMessage);
// Send the HelloWorld message by calling publishMessage on the
// wormhole core contract and paying the Wormhole protocol fee.
messageSequence = wormhole.publishMessage{value: wormholeFee}(
0, // batchID
encodedMessage,
wormholeFinality()
);
```
View the complete Hello World example in the [Wormhole Scaffolding](https://github.com/wormhole-foundation/wormhole-scaffolding/tree/main/evm/src/01_hello_world){target=\_blank} repository on GitHub.
=== "Solana"
The `wormhole_anchor_sdk::wormhole` module and the Wormhole program account can be used to pass a message directly to the Core Contract via the `wormhole::post_message` function:
```rs
pub fn post_message<'info>(
ctx: CpiContext<'_, '_, '_, 'info, PostMessage<'info>>,
batch_id: u32,
payload: Vec,
finality: Finality
) -> Result<()>
```
??? interface "Parameters"
`ctx` ++"CpiContext<'_, '_, '_, 'info, PostMessage<'info>>"++
Provides the necessary context for executing the function, including the accounts and program information required for the Cross-Program Invocation (CPI).
??? child "Type `pub struct CpiContext<'a, 'b, 'c, 'info, T>`"
```rs
pub struct CpiContext<'a, 'b, 'c, 'info, T>
where
T: ToAccountMetas + ToAccountInfos<'info>,
{
pub accounts: T,
pub remaining_accounts: Vec>,
pub program: AccountInfo<'info>,
pub signer_seeds: &'a [&'b [&'c [u8]]],
}
```
For more information, please refer to the [`wormhole_anchor_sdk` Rust docs](https://docs.rs/anchor-lang/0.29.0/anchor_lang/context/struct.CpiContext.html){target=\_blank}.
??? child "Type `PostMessage<'info>`"
```rs
pub struct PostMessage<'info> {
pub config: AccountInfo<'info>,
pub message: AccountInfo<'info>,
pub emitter: AccountInfo<'info>,
pub sequence: AccountInfo<'info>,
pub payer: AccountInfo<'info>,
pub fee_collector: AccountInfo<'info>,
pub clock: AccountInfo<'info>,
pub rent: AccountInfo<'info>,
pub system_program: AccountInfo<'info>,
}
```
For more information, please refer to the [`wormhole_anchor_sdk` Rust docs](https://docs.rs/wormhole-anchor-sdk/latest/wormhole_anchor_sdk/wormhole/instructions/struct.PostMessage.html){target=\_blank}.
---
`batch_id` ++"u32"++
An identifier for the message batch.
---
`payload` ++"Vec"++
The data being sent in the message. This is a variable-length byte array that contains the actual content or information being transmitted. To learn about the different types of payloads, check out the [VAAs](/docs/protocol/infrastructure/vaas#payload-types){target=\_blank} page.
---
`finality` ++"Finality"++
Specifies the level of finality or confirmation required for the message.
??? child "Type `Finality`"
```rs
pub enum Finality {
Confirmed,
Finalized,
}
```
??? interface "Returns"
++"Result<()>"++
The result of the function’s execution. If the function completes successfully, it returns `Ok(())`, otherwise it returns `Err(E)`, indicating that an error occurred along with the details about the error
??? interface "Example"
```rust
let fee = ctx.accounts.wormhole_bridge.fee();
// ... Check fee and send parameters
let config = &ctx.accounts.config
let payload: Vec = HelloWorldMessage::Hello { message }.try_to_vec()?;
// Invoke `wormhole::post_message`.
wormhole::post_message(
CpiContext::new_with_signer(
ctx.accounts.wormhole_program.to_account_info(),
wormhole::PostMessage {
// ... Set fields
},
&[
// ... Set seeds
],
),
config.batch_id,
payload,
config.finality.into(),
)?;
```
View the complete Hello World example in the [Wormhole Scaffolding](https://github.com/wormhole-foundation/wormhole-scaffolding/tree/main/solana/programs/01_hello_world){target=\_blank} repository on GitHub.
Once the message is emitted from the Core Contract, the [Guardian Network](/docs/protocol/infrastructure/guardians/){target=\_blank} will observe the message and sign the digest of an Attestation [VAA](/docs/protocol/infrastructure/vaas/){target=\_blank}. On EVM chains, the body of the VAA is hashed twice with keccak256 to produce the signed digest message. On Solana, the [Solana secp256k1 program](https://solana.com/docs/core/programs#secp256k1-program){target=\_blank} will hash the message passed. In this case, the argument for the message should be a single hash of the body, not the twice-hashed body.
VAAs are [multicast](/docs/protocol/infrastructure/core-contracts/#multicast){target=\_blank} by default. This means there is no default target chain for a given message. The application developer decides on the format of the message and its treatment upon receipt.
### Receiving Messages
The way a message is received and handled depends on the environment.
=== "EVM"
On EVM chains, the message passed is the raw VAA encoded as binary. The `IWormhole.sol` interface provides the `parseAndVerifyVM` function, which can be used to parse and verify the received message.
```solidity
function parseAndVerifyVM(
bytes calldata encodedVM
) external view returns (VM memory vm, bool valid, string memory reason);
```
??? interface "Parameters"
`encodedVM` ++"bytes calldata"++
The encoded message as a Verified Action Approval (VAA), which contains all necessary information for verification and processing.
??? interface "Returns"
`vm` ++"VM memory"++
The valid parsed VAA, which will include the original `emitterAddress`, `sequenceNumber`, and `consistencyLevel`, among other fields outlined on the [VAAs](/docs/protocol/infrastructure/vaas/) page.
??? child "Struct `VM`"
```solidity
struct VM {
uint8 version;
uint32 timestamp;
uint32 nonce;
uint16 emitterChainId;
bytes32 emitterAddress;
uint64 sequence;
uint8 consistencyLevel;
bytes payload;
uint32 guardianSetIndex;
Signature[] signatures;
bytes32 hash;
}
```
For more information, refer to the [`IWormhole.sol` interface](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/interfaces/IWormhole.sol){target=\_blank}.
---
`valid` ++"bool"++
A boolean indicating whether the VAA is valid or not.
---
`reason` ++"string"++
If the VAA is not valid, a reason will be provided
??? interface "Example"
```solidity
function receiveMessage(bytes memory encodedMessage) public {
// Call the Wormhole core contract to parse and verify the encodedMessage
(
IWormhole.VM memory wormholeMessage,
bool valid,
string memory reason
) = wormhole().parseAndVerifyVM(encodedMessage);
// Perform safety checks here
// Decode the message payload into the HelloWorldMessage struct
HelloWorldMessage memory parsedMessage = decodeMessage(
wormholeMessage.payload
);
// Your custom application logic here
}
```
View the complete Hello World example in the [Wormhole Scaffolding](https://github.com/wormhole-foundation/wormhole-scaffolding/tree/main/evm/src/01_hello_world){target=\_blank} repository on GitHub.
=== "Solana"
On Solana, the VAA is first posted and verified by the Core Contract, after which it can be read by the receiving contract and action taken.
Retrieve the raw message data:
```rs
let posted_message = &ctx.accounts.posted;
posted_message.data()
```
??? interface "Example"
```rust
pub fn receive_message(ctx: Context, vaa_hash: [u8; 32]) -> Result<()> {
let posted_message = &ctx.accounts.posted
if let HelloWorldMessage::Hello { message } = posted_message.data() {
// Check message
// Your custom application logic here
Ok(())
} else {
Err(HelloWorldError::InvalidMessage.into())
}
}
```
View the complete Hello World example in the [Wormhole Scaffolding](https://github.com/wormhole-foundation/wormhole-scaffolding/tree/main/solana/programs/01_hello_world){target=\_blank} repository on GitHub.
#### Validating the Emitter
When processing cross-chain messages, it's critical to ensure that the message originates from a trusted sender (emitter). This can be done by verifying the emitter address and chain ID in the parsed VAA.
Typically, contracts should provide a method to register trusted emitters and check incoming messages against this list before processing them. For example, the following check ensures that the emitter is registered and authorized:
```solidity
require(isRegisteredSender(emitterChainId, emitterAddress), "Invalid emitter");
```
This check can be applied after the VAA is parsed, ensuring only authorized senders can interact with the receiving contract. Trusted emitters can be registered using a method like `setRegisteredSender` during contract deployment or initialization.
```typescript
const tx = await receiverContract.setRegisteredSender(
sourceChain.chainId,
ethers.zeroPadValue(senderAddress as BytesLike, 32)
);
await tx.wait();
```
#### Additional Checks
In addition to environment-specific checks that should be performed, a contract should take care to check other [fields in the body](/docs/protocol/infrastructure/vaas/){target=\_blank}, including:
- **Sequence**: Is this the expected sequence number? How should out-of-order deliveries be handled?
- **Consistency level**: For the chain this message came from, is the [Wormhole Finality](/docs/products/reference/consistency-levels/){target=\_blank} level enough to guarantee the transaction won't be reverted after taking some action?
The VAA digest is separate from the VAA body but is also relevant. It can be used for replay protection by checking if the digest has already been seen. Since the payload itself is application-specific, there may be other elements to check to ensure safety.
## Source Code References
For a deeper understanding of the Core Contract implementation for a specific blockchain environment and to review the actual source code, please refer to the following links:
- [Algorand Core Contract source code](https://github.com/wormhole-foundation/wormhole/blob/main/algorand/wormhole_core.py){target=\_blank}
- [Aptos Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/aptos/wormhole){target=\_blank}
- [EVM Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/ethereum/contracts){target=\_blank} ([`IWormhole.sol` interface](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/interfaces/IWormhole.sol){target=\_blank})
- [NEAR Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/near/contracts/wormhole){target=\_blank}
- [Solana Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/solana/bridge/program){target=\_blank}
- [Sui Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/sui/wormhole){target=\_blank}
- [Terra Core Contract source code](https://github.com/wormhole-foundation/wormhole/tree/main/terra/contracts/wormhole){target=\_blank}
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/solana-shims/sol-emission.md
--- BEGIN CONTENT ---
---
title: Solana Message Emission via Shim
description: Learn how to reduce rent costs when emitting Wormhole messages on Solana by using the emission shim instead of post_message.
categories: Basics
---
# Solana Message Emission via Shim
The emission shim is a lightweight Solana program that lets integrators emit Wormhole messages without creating a new rent-exempt account for every message. It passes an empty payload to the core bridge and emits the message data through transaction logs, reducing rent costs and avoiding state bloat while remaining fully compatible with Guardian observation.
Migrating from the legacy path is straightforward: no account resizing is needed, and programs can call the shim directly. The Wormhole fee is still paid through the `fee_collector`, with the same parallelization limits as before.
Guardians are configured to observe the canonical shim address, reading message data, emitter, and nonce from the transaction logs and CPI events, rather than on-chain accounts. They also ignore the empty core bridge payload to prevent duplicate VAAs. On mainnet, all 19 Guardians support shim emissions, and, as with all Wormhole messages, at least 13 attestations are required for a valid VAA.
!!!note
For on-chain programs that only call the shim via CPI, consider emitting a dummy/empty message after migration to avoid edge cases with initial CPI depth (Solana limits the depth of cross-program calls).
For more background, see [Emission Shim concept section](/docs/products/messaging/concepts/solana-shim/#emission-shim){target=\_blank}.
## Prerequisites
To interact with the emission shim, you'll need the following:
- [Rust and Solana CLI](https://docs.solana.com/cli/install-solana-cli-tools){target=\_blank} installed.
- [Anchor installed](https://www.anchor-lang.com/docs/installation){target=\_blank}.
- The canonical emission shim program already deployed at [`EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX`](https://explorer.solana.com/address/EtZMZM22ViKMo4r5y4Anovs3wKQ2owUmDpjygnMMcdEX){target=\_blank}.
- The shim’s [IDL](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/idls/wormhole_post_message_shim.json){target=\_blank} for wiring accounts.
- A payer (signer) funded with enough SOL to cover compute and message fees.
## Setup
To start, import the shim crate to call `wormhole_post_message_shim::cpi::post_message`. Then, pull the core bridge addresses needed to be passed along.
```rs
declare_program!(wormhole_post_message_shim);
use anchor_lang::prelude::*;
use wormhole_post_message_shim::{program::WormholePostMessageShim, types::Finality};
use wormhole_solana_consts::{
CORE_BRIDGE_CONFIG, CORE_BRIDGE_FEE_COLLECTOR, CORE_BRIDGE_PROGRAM_ID,
};
#[derive(Accounts)]
pub struct PostMessage<'info> {
#[account(mut)]
payer: Signer<'info>,
wormhole_post_message_shim: Program<'info, WormholePostMessageShim>,
#[account(mut, address = CORE_BRIDGE_CONFIG)]
/// CHECK: Wormhole bridge config. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub bridge: UncheckedAccount<'info>,
#[account(mut, seeds = [&emitter.key.to_bytes()], bump, seeds::program = wormhole_post_message_shim::ID)]
/// CHECK: Wormhole Message. [`wormhole::post_message`] requires this account be signer and mutable.
/// Seeds constraint added for IDL generation / convenience, it will be enforced by the shim.
pub message: UncheckedAccount<'info>,
#[account(seeds = [b"emitter"], bump)]
/// CHECK: Our emitter
/// Seeds constraint added for IDL generation / convenience, it will be enforced to match the signer used in the CPI call.
pub emitter: UncheckedAccount<'info>,
#[account(mut)]
/// CHECK: Emitter's sequence account. [`wormhole::post_message`] requires this account be mutable.
/// Explicitly do not re-derive this account. The core bridge verifies the derivation anyway and
/// as of Anchor 0.30.1, auto-derivation for other programs' accounts via IDL doesn't work.
pub sequence: UncheckedAccount<'info>,
#[account(mut, address = CORE_BRIDGE_FEE_COLLECTOR)]
/// CHECK: Wormhole fee collector. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub fee_collector: UncheckedAccount<'info>,
/// Clock sysvar.
/// Type added for IDL generation / convenience, it will be enforced by the core bridge.
pub clock: Sysvar<'info, Clock>,
/// System program.
/// Type for IDL generation / convenience, it will be enforced by the core bridge.
pub system_program: Program<'info, System>,
#[account(address = CORE_BRIDGE_PROGRAM_ID)]
/// CHECK: Wormhole program.
/// Address constraint added for IDL generation / convenience, it will be enforced by the shim.
pub wormhole_program: UncheckedAccount<'info>,
/// CHECK: Shim event authority
/// TODO: An address constraint could be included if this address was published to wormhole_solana_consts
/// Address will be enforced by the shim.
pub wormhole_post_message_shim_ea: UncheckedAccount<'info>,
}
pub fn post_message(ctx: Context) -> Result<()> {
// wormhole::post_message may require that a fee be sent to the fee_collector account of the core bridge.
// The following code could be used to handle this via CPI call.
// However, this example handles this complexity on the client side using a `preInstruction`
//
// let fee = ctx.accounts.wormhole_bridge.fee();
// if fee > 0 {
// solana_program::program::invoke(
// &solana_program::system_instruction::transfer(
// &ctx.accounts.payer.key(),
// &ctx.accounts.fee_collector.key(),
// fee,
// ),
// &ctx.accounts.to_account_infos(),
// )?;
// }
wormhole_post_message_shim::cpi::post_message(
CpiContext::new_with_signer(
ctx.accounts.wormhole_post_message_shim.to_account_info(),
wormhole_post_message_shim::cpi::accounts::PostMessage {
payer: ctx.accounts.payer.to_account_info(),
bridge: ctx.accounts.bridge.to_account_info(),
message: ctx.accounts.message.to_account_info(),
emitter: ctx.accounts.emitter.to_account_info(),
sequence: ctx.accounts.sequence.to_account_info(),
fee_collector: ctx.accounts.fee_collector.to_account_info(),
clock: ctx.accounts.clock.to_account_info(),
system_program: ctx.accounts.system_program.to_account_info(),
wormhole_program: ctx.accounts.wormhole_program.to_account_info(),
program: ctx.accounts.wormhole_post_message_shim.to_account_info(),
event_authority: ctx.accounts.wormhole_post_message_shim_ea.to_account_info(),
},
&[&[b"emitter", &[ctx.bumps.emitter]]],
),
0,
Finality::Finalized,
b"your message goes here!".to_vec(),
)?;
Ok(())
}
```
## Accounts
When calling the shim’s `post_message` instruction, you need to pass:
- `bridge`: Holds the Wormhole core bridge config.
- `message`: Represents the PDA derived from the emitter and is reused by the shim instead of generating new accounts.
- `emitter`: Serves as the emitter address (signer).
- `sequence`: Tracks the emitter's sequence account.
- `payer`: Pays compute and any rent needed on first use (signer).
- `fee_collector`: Collects the Wormhole message fee.
- `clock`: Provides the current Solana time from the sysvar.
- `system_program`: Supplies the standard Solana system program for account creation on first use.
- `wormhole_program`: Points to the Wormhole core bridge program.
- `event_authority`: Acts as the PDA used by the shim to emit log events (Anchor CPI events).
- `program`: Specifies the shim program itself.
The struct below defines the accounts required by your instruction and wires the shim to the core bridge, ensuring the emitter PDA can sign the CPI via seeds.
```rs
pub struct PostMessage<'info> {
#[account(mut)]
payer: Signer<'info>,
wormhole_post_message_shim: Program<'info, WormholePostMessageShim>,
#[account(mut, address = CORE_BRIDGE_CONFIG)]
/// CHECK: Wormhole bridge config. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub bridge: UncheckedAccount<'info>,
#[account(mut, seeds = [&emitter.key.to_bytes()], bump, seeds::program = wormhole_post_message_shim::ID)]
/// CHECK: Wormhole Message. [`wormhole::post_message`] requires this account be signer and mutable.
/// Seeds constraint added for IDL generation / convenience, it will be enforced by the shim.
pub message: UncheckedAccount<'info>,
#[account(seeds = [b"emitter"], bump)]
/// CHECK: Our emitter
/// Seeds constraint added for IDL generation / convenience, it will be enforced to match the signer used in the CPI call.
pub emitter: UncheckedAccount<'info>,
#[account(mut)]
/// CHECK: Emitter's sequence account. [`wormhole::post_message`] requires this account be mutable.
/// Explicitly do not re-derive this account. The core bridge verifies the derivation anyway and
/// as of Anchor 0.30.1, auto-derivation for other programs' accounts via IDL doesn't work.
pub sequence: UncheckedAccount<'info>,
#[account(mut, address = CORE_BRIDGE_FEE_COLLECTOR)]
/// CHECK: Wormhole fee collector. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub fee_collector: UncheckedAccount<'info>,
/// Clock sysvar.
/// Type added for IDL generation / convenience, it will be enforced by the core bridge.
pub clock: Sysvar<'info, Clock>,
/// System program.
/// Type for IDL generation / convenience, it will be enforced by the core bridge.
pub system_program: Program<'info, System>,
#[account(address = CORE_BRIDGE_PROGRAM_ID)]
/// CHECK: Wormhole program.
/// Address constraint added for IDL generation / convenience, it will be enforced by the shim.
pub wormhole_program: UncheckedAccount<'info>,
/// CHECK: Shim event authority
/// TODO: An address constraint could be included if this address was published to wormhole_solana_consts
/// Address will be enforced by the shim.
pub wormhole_post_message_shim_ea: UncheckedAccount<'info>,
}
```
This instruction reuses a single per-emitter message PDA (no per-message rent). When invoked, the shim emits your payload as an Anchor CPI event and, in the same transaction, calls the core bridge with an empty payload, allowing the core bridge to still assign the sequence and enforce fees/finality. Guardians read the Core call (sequence/finality) and the shim event (payload) from the transaction logs, producing a standard VAA without leaving a persistent message account.
## Call post_message
The `post_message` function builds a `CpiContext` and invokes the shim’s `post_message` instruction, forwarding the nonce, finality, and your payload. The Core Bridge enforces fee requirements and assigns the sequence, while the shim emits the payload as an event in the same transaction.
```rs
declare_program!(wormhole_post_message_shim);
use anchor_lang::prelude::*;
use wormhole_post_message_shim::{program::WormholePostMessageShim, types::Finality};
use wormhole_solana_consts::{
CORE_BRIDGE_CONFIG, CORE_BRIDGE_FEE_COLLECTOR, CORE_BRIDGE_PROGRAM_ID,
};
#[derive(Accounts)]
pub struct PostMessage<'info> {
#[account(mut)]
payer: Signer<'info>,
wormhole_post_message_shim: Program<'info, WormholePostMessageShim>,
#[account(mut, address = CORE_BRIDGE_CONFIG)]
/// CHECK: Wormhole bridge config. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub bridge: UncheckedAccount<'info>,
#[account(mut, seeds = [&emitter.key.to_bytes()], bump, seeds::program = wormhole_post_message_shim::ID)]
/// CHECK: Wormhole Message. [`wormhole::post_message`] requires this account be signer and mutable.
/// Seeds constraint added for IDL generation / convenience, it will be enforced by the shim.
pub message: UncheckedAccount<'info>,
#[account(seeds = [b"emitter"], bump)]
/// CHECK: Our emitter
/// Seeds constraint added for IDL generation / convenience, it will be enforced to match the signer used in the CPI call.
pub emitter: UncheckedAccount<'info>,
#[account(mut)]
/// CHECK: Emitter's sequence account. [`wormhole::post_message`] requires this account be mutable.
/// Explicitly do not re-derive this account. The core bridge verifies the derivation anyway and
/// as of Anchor 0.30.1, auto-derivation for other programs' accounts via IDL doesn't work.
pub sequence: UncheckedAccount<'info>,
#[account(mut, address = CORE_BRIDGE_FEE_COLLECTOR)]
/// CHECK: Wormhole fee collector. [`wormhole::post_message`] requires this account be mutable.
/// Address constraint added for IDL generation / convenience, it will be enforced by the core bridge.
pub fee_collector: UncheckedAccount<'info>,
/// Clock sysvar.
/// Type added for IDL generation / convenience, it will be enforced by the core bridge.
pub clock: Sysvar<'info, Clock>,
/// System program.
/// Type for IDL generation / convenience, it will be enforced by the core bridge.
pub system_program: Program<'info, System>,
#[account(address = CORE_BRIDGE_PROGRAM_ID)]
/// CHECK: Wormhole program.
/// Address constraint added for IDL generation / convenience, it will be enforced by the shim.
pub wormhole_program: UncheckedAccount<'info>,
/// CHECK: Shim event authority
/// TODO: An address constraint could be included if this address was published to wormhole_solana_consts
/// Address will be enforced by the shim.
pub wormhole_post_message_shim_ea: UncheckedAccount<'info>,
}
pub fn post_message(ctx: Context) -> Result<()> {
// wormhole::post_message may require that a fee be sent to the fee_collector account of the core bridge.
// The following code could be used to handle this via CPI call.
// However, this example handles this complexity on the client side using a `preInstruction`
//
// let fee = ctx.accounts.wormhole_bridge.fee();
// if fee > 0 {
// solana_program::program::invoke(
// &solana_program::system_instruction::transfer(
// &ctx.accounts.payer.key(),
// &ctx.accounts.fee_collector.key(),
// fee,
// ),
// &ctx.accounts.to_account_infos(),
// )?;
// }
wormhole_post_message_shim::cpi::post_message(
CpiContext::new_with_signer(
ctx.accounts.wormhole_post_message_shim.to_account_info(),
wormhole_post_message_shim::cpi::accounts::PostMessage {
payer: ctx.accounts.payer.to_account_info(),
bridge: ctx.accounts.bridge.to_account_info(),
message: ctx.accounts.message.to_account_info(),
emitter: ctx.accounts.emitter.to_account_info(),
sequence: ctx.accounts.sequence.to_account_info(),
fee_collector: ctx.accounts.fee_collector.to_account_info(),
clock: ctx.accounts.clock.to_account_info(),
system_program: ctx.accounts.system_program.to_account_info(),
wormhole_program: ctx.accounts.wormhole_program.to_account_info(),
program: ctx.accounts.wormhole_post_message_shim.to_account_info(),
event_authority: ctx.accounts.wormhole_post_message_shim_ea.to_account_info(),
},
&[&[b"emitter", &[ctx.bumps.emitter]]],
),
0,
Finality::Finalized,
b"your message goes here!".to_vec(),
)?;
Ok(())
}
```
## Limitations and Considerations
- **Rent**: No persistent account rent is paid for every emission; the cost is now dominated by compute and the emission fee.
- **Logs**: Since all observability is log-based, re-observation is only possible while Solana transaction history is available.
- **Parallelization**: Still limited by the `fee_collector` account being mutable.
- **CPI Depth**: The first shim call for an emitter adds one extra stack depth. This is only relevant if you are near the Solana CPI limit (4).
## Conclusion
By using the emission shim, you can dramatically reduce rent costs when emitting Wormhole messages from Solana, while ensuring compatibility with Guardian observation and core bridge sequencing.
For a complete, working reference, see the full example implementation in the Wormhole repo: [`post_message.rs`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/programs/wormhole-integrator-example/src/instructions/post_message.rs){target=\_blank}.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/solana-shims/sol-verification.md
--- BEGIN CONTENT ---
---
title: Solana VAA Verification via Shim
description: Efficiently verify Wormhole VAAs on Solana using the Verification Shim, which avoids persistent rent-exempt accounts while keeping full security guarantees.
categories: Basics
---
# Solana VAA Verification via Shim
Verifying VAAs on Solana with the legacy core bridge requires creating multiple rent-exempt accounts for signatures and posted VAAs. These accounts persist even after verification is complete, which increases costs and bloats the on-chain state.
The verification shim solves this by replacing the core bridge verification flow with its own instructions:
- `post_signatures`: Accumulates Guardian signatures into a temporary account.
- `verify_hash`: Validates the VAA by checking the signatures against the active Guardian set and ensuring quorum.
- `close_signatures`: Closes the temporary account to reclaim lamports.
Because the shim avoids leaving permanent accounts behind, verification becomes much cheaper while keeping the same security guarantees.
This page introduces the Verification Shim, explains how it works, and shows how integrators can adopt it in place of the core bridge’s `verify_signatures` and `post_vaa` functions.
For more background, see the [Verification Shim concept section](/docs/products/messaging/concepts/solana-shim/#verification-shim){target=\_blank}.
## Prerequisites
To interact with the verification shim, you'll need the following:
- [Rust and Solana CLI installed](https://docs.solana.com/cli/install-solana-cli-tools){target=\_blank}.
- [Anchor installed](https://www.anchor-lang.com/docs/installation){target=\_blank}.
- The canonical verification shim program already deployed at [`EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at`](https://explorer.solana.com/address/EFaNWErqAtVWufdNb7yofSHHfWFos843DFpu4JBw24at){target=\_blank}.
- The shim’s [IDL](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/idls/wormhole_verify_vaa_shim.json){target=\_blank} for wiring accounts.
- A payer (signer) funded for compute and temporary account rent (you’ll close and reclaim).
## Setup
To start, add the verification shim CPI and declare the external program so your instruction can CPI into it. This lets your program verify a VAA digest against the active Guardian set without creating persistent core bridge accounts.
```rs
declare_program!(wormhole_verify_vaa_shim);
use anchor_lang::{
prelude::*,
solana_program::{self, keccak},
};
use wormhole_verify_vaa_shim::cpi::accounts::VerifyHash;
use wormhole_verify_vaa_shim::program::WormholeVerifyVaaShim;
#[derive(Accounts)]
pub struct ConsumeVaa<'info> {
/// CHECK: Guardian set used for signature verification by shim.
/// Derivation is checked by the shim.
guardian_set: UncheckedAccount<'info>,
/// CHECK: Stored guardian signatures to be verified by shim.
/// Ownership ownership and discriminator is checked by the shim.
guardian_signatures: UncheckedAccount<'info>,
wormhole_verify_vaa_shim: Program<'info, WormholeVerifyVaaShim>,
}
pub fn consume_vaa(
ctx: Context,
guardian_set_bump: u8,
vaa_body: Vec,
) -> Result<()> {
// Compute the message hash.
let message_hash = &solana_program::keccak::hashv(&[&vaa_body]).to_bytes();
let digest = keccak::hash(message_hash.as_slice()).to_bytes();
// Verify the hash against the signatures.
wormhole_verify_vaa_shim::cpi::verify_hash(
CpiContext::new(
ctx.accounts.wormhole_verify_vaa_shim.to_account_info(),
VerifyHash {
guardian_set: ctx.accounts.guardian_set.to_account_info(),
guardian_signatures: ctx.accounts.guardian_signatures.to_account_info(),
},
),
guardian_set_bump,
digest,
)?;
// Decode vaa_body, perform security checks, and do your thing.
Ok(())
}
```
## Accounts
You’ll wire three accounts for verification:
- `guardian_set`: Core bridge `GuardianSet` PDA for the VAA’s `guardianSetIndex` (shim checks derivation).
- `guardian_signatures`: Temporary account created by `post_signatures` (shim checks ownership & discriminator).
- `wormhole_verify_vaa_shim`: The verification shim program.
```rs
pub struct ConsumeVaa<'info> {
/// CHECK: Guardian set used for signature verification by shim.
/// Derivation is checked by the shim.
guardian_set: UncheckedAccount<'info>,
/// CHECK: Stored guardian signatures to be verified by shim.
/// Ownership ownership and discriminator is checked by the shim.
guardian_signatures: UncheckedAccount<'info>,
wormhole_verify_vaa_shim: Program<'info, WormholeVerifyVaaShim>,
}
```
Here, `guardian_set` is a core bridge PDA, and `guardian_signatures` is created and owned by the verification shim. Derive `guardian_set = PDA(["GuardianSet", index_be_bytes], CORE_BRIDGE_PROGRAM_ID)` using the `guardianSetIndex` from the VAA header (big-endian), compute its bump, and pass that bump into your instruction.
## Verify the VAA
The `consume_vaa` function computes the digest, calls the shim’s `verify_hash`, and then proceeds with your logic. This step validates Guardian signatures and quorum against the active Guardian set for the VAA’s `guardianSetIndex`, then lets your program proceed without persisting a `PostedVAA`.
```rs
declare_program!(wormhole_verify_vaa_shim);
use anchor_lang::{
prelude::*,
solana_program::{self, keccak},
};
use wormhole_verify_vaa_shim::cpi::accounts::VerifyHash;
use wormhole_verify_vaa_shim::program::WormholeVerifyVaaShim;
#[derive(Accounts)]
pub struct ConsumeVaa<'info> {
/// CHECK: Guardian set used for signature verification by shim.
/// Derivation is checked by the shim.
guardian_set: UncheckedAccount<'info>,
/// CHECK: Stored guardian signatures to be verified by shim.
/// Ownership ownership and discriminator is checked by the shim.
guardian_signatures: UncheckedAccount<'info>,
wormhole_verify_vaa_shim: Program<'info, WormholeVerifyVaaShim>,
}
pub fn consume_vaa(
ctx: Context,
guardian_set_bump: u8,
vaa_body: Vec,
) -> Result<()> {
// Compute the message hash.
let message_hash = &solana_program::keccak::hashv(&[&vaa_body]).to_bytes();
let digest = keccak::hash(message_hash.as_slice()).to_bytes();
// Verify the hash against the signatures.
wormhole_verify_vaa_shim::cpi::verify_hash(
CpiContext::new(
ctx.accounts.wormhole_verify_vaa_shim.to_account_info(),
VerifyHash {
guardian_set: ctx.accounts.guardian_set.to_account_info(),
guardian_signatures: ctx.accounts.guardian_signatures.to_account_info(),
},
),
guardian_set_bump,
digest,
)?;
// Decode vaa_body, perform security checks, and do your thing.
Ok(())
}
```
## Limitations and Security Considerations
- You must be the payer and/or account owner to reclaim lamports from the `GuardianSignatures` account.
- The verification proof is not a permanent on-chain record unless you keep the account.
- Compute usage (CU) is higher for the rent-efficient pattern, but the total cost is dramatically lower than keeping permanent accounts.
- All validation guarantees remain as strong as with the legacy method.
- If you do not close accounts you create, rent will be lost as before.
- This approach assumes you do not need to later re-validate the VAA from an on-chain artifact.
## Conclusion
By following this flow, you can efficiently verify VAAs on Solana with minimal rent overhead, leaving no unnecessary state behind on-chain. For a complete, working reference, see the full example implementation in the Wormhole repo: [`consume_vaa.rs`](https://github.com/wormhole-foundation/wormhole/blob/main/svm/wormhole-core-shims/anchor/programs/wormhole-integrator-example/src/instructions/consume_vaa.rs){target=\_blank}.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/guides/wormhole-relayers.md
--- BEGIN CONTENT ---
---
title: Wormhole-Deployed Relayers
description: Learn about the Wormhole-deployed relayer configuration for seamless cross-chain messaging between contracts on different EVM blockchains without off-chain deployments.
categories: Relayers, Basics
---
# Wormhole Relayer
The Wormhole-deployed relayers provide a mechanism for contracts on one blockchain to send messages to contracts on another without requiring off-chain infrastructure. Through the Wormhole relayer module, developers can use an untrusted delivery provider to transport VAAs, saving the need to build and maintain custom relaying solutions. The option to [run a custom relayer](/docs/protocol/infrastructure-guides/run-relayer/) is available for more complex needs.
This section covers the components and interfaces involved in using the Wormhole relayer module, such as message sending and receiving, delivery guarantees, and considerations for building reliable and efficient cross-chain applications. Additionally, you'll find details on how to handle specific implementation scenarios and track message delivery progress using the Wormhole CLI tool.
## Get Started with the Wormhole Relayer
Before getting started, it's important to note that the Wormhole-deployed relayer configuration is currently **limited to EVM environments**. The complete list of EVM environment blockchains is on the [Supported Networks](/docs/products/reference/supported-networks/) page.
To interact with the Wormhole relayer, you'll need to create contracts on the source and target chains to handle the sending and receiving of messages. No off-chain logic needs to be implemented to take advantage of Wormhole-powered relaying.

The components outlined in blue must be implemented.
### Wormhole Relayer Interfaces
There are three relevant interfaces to discuss when utilizing the Wormhole relayer module:
- **[`IWormholeRelayer`](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayer.sol){target=\_blank}**: The primary interface by which you send and receive messages. It allows you to request the sending of messages and VAAs.
- **[`IWormholeReceiver`](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeReceiver.sol){target=\_blank}**: This is the interface you are responsible for implementing. It allows the selected delivery provider to deliver messages/VAAs to your contract.
- **[`IDeliveryProvider`](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IDeliveryProvider.sol){target=\_blank}**: This interface represents the delivery pricing information for a given relayer network. Each delivery provider implements this on every blockchain they support delivering from.
## Interact with the Wormhole Relayer
To start interacting with the Wormhole relayer in your contracts, you'll need to import the `IWormholeRelayer` interface and set up a reference using the contract address to the Wormhole-deployed relayer on the supported network of your choice.
To easily integrate with the Wormhole relayer interface, you can use the [Wormhole Solidity SDK](https://github.com/wormhole-foundation/wormhole-solidity-sdk){target=\_blank}.
To retrieve the contract address of the Wormhole relayer, refer to the Wormhole relayer section on the [Contract Addresses](/docs/products/reference/contract-addresses/#wormhole-relayer) reference page.
Your initial set up should resemble the following:
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.26;
import "wormhole-solidity-sdk/interfaces/IWormholeRelayer.sol";
contract Example {
IWormholeRelayer public wormholeRelayer;
constructor(address _wormholeRelayer) {
wormholeRelayer = IWormholeRelayer(_wormholeRelayer);
}
}
```
The code provided sets up the basic structure for your contract to interact with the Wormhole relayer using the address supplied to the constructor. By leveraging methods from the `IWormholeRelayer` interface, you can implement message sending and receiving functionalities. The following sections will detail the specific methods you need to use for these tasks.
### Send a Message
To send a message to a contract on another EVM chain, you can call the `sendPayloadToEvm` method provided by the `IWormholeRelayer` interface.
```solidity
function sendPayloadToEvm(
// Chain ID in Wormhole format
uint16 targetChain,
// Contract Address on target chain we're sending a message to
address targetAddress,
// The payload, encoded as bytes
bytes memory payload,
// How much value to attach to the delivery transaction
uint256 receiverValue,
// The gas limit to set on the delivery transaction
uint256 gasLimit
) external payable returns (
// Unique, incrementing ID, used to identify a message
uint64 sequence
);
```
!!! tip
To reduce transaction confirmation time, you can lower the consistency level using the [`sendToEvm`](https://github.com/wormhole-foundation/wormhole/blob/v{{repositories.wormhole.version}}/sdk/js/src/relayer/relayer/send.ts#L33){target=\_blank} method.
The `sendPayloadToEvm` method is marked `payable` to receive fee payment for the transaction. The value to attach to the invocation is determined by calling the `quoteEVMDeliveryPrice`, which provides an estimate of the cost of gas on the target chain.
```solidity
function quoteEVMDeliveryPrice(
// Chain ID in Wormhole format
uint16 targetChain,
// How much value to attach to delivery transaction
uint256 receiverValue,
// The gas limit to attach to the delivery transaction
uint256 gasLimit
) external view returns (
// How much value to attach to the send call
uint256 nativePriceQuote,
uint256 targetChainRefundPerGasUnused
);
```
This method should be called before sending a message, and the value returned for `nativePriceQuote` should be attached to the call to send the payload to cover the transaction's cost on the target chain.
In total, sending a message across EVM chains can be as simple as getting a fee quote and sending the message as follows:
```solidity
// Get a quote for the cost of gas for delivery
(cost, ) = wormholeRelayer.quoteEVMDeliveryPrice(
targetChain,
valueToSend,
GAS_LIMIT
);
// Send the message
wormholeRelayer.sendPayloadToEvm{value: cost}(
targetChain,
targetAddress,
abi.encode(payload),
valueToSend,
GAS_LIMIT
);
```
### Receive a Message
To receive a message using a Wormhole relayer, the target contract must implement the [`IWormholeReceiver`](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeReceiver.sol){target=\_blank} interface, as shown in the [previous section](#interact-with-the-wormhole-relayer).
```solidity
function receiveWormholeMessages(
bytes memory payload, // Message passed by source contract
bytes[] memory additionalVaas, // Any additional VAAs that are needed (Note: these are unverified)
bytes32 sourceAddress, // The address of the source contract
uint16 sourceChain, // The Wormhole chain ID
bytes32 deliveryHash // A hash of contents, useful for replay protection
) external payable;
```
The logic inside the function body may be whatever business logic is required to take action on the specific payload.
## Delivery Guarantees
The Wormhole relayer protocol is intended to create a service interface whereby mutually distrustful integrators and delivery providers can work together to provide a seamless dApp experience. You don't trust the delivery providers with your data, and the delivery providers don't trust your smart contract. The primary agreement between integrators and delivery providers is that when a delivery is requested, the provider will attempt to deliver the VAA within the provider's stated delivery timeframe.
This creates a marketplace whereby providers can set different price levels and service guarantees. Delivery providers effectively accept the slippage risk premium of delivering your VAAs in exchange for a set fee rate. Thus, the providers agree to deliver your messages even if they do so at a loss.
Delivery providers should set their prices such that they turn a profit on average but not necessarily on every single transfer. Thus, some providers may choose to set higher rates for tighter guarantees or lower rates for less stringent guarantees.
## Delivery Statuses
All deliveries result in one of the following four outcomes before the delivery provider's delivery timeframe. When they occur, these outcomes are emitted as EVM events from the Wormhole relayer contract. The four possible outcomes are:
- (0) Delivery Success
- (1) Receiver Failure
- (2) Forward Request Success
- (3) Forward Request Failure
A receiver failure is a scenario in which the selected provider attempted the delivery but it could not be completely successfully. The three possible causes for a delivery failure are:
- The target contract does not implement the `IWormholeReceiver` interface.
- The target contract threw an exception or reverted during the execution of `receiveWormholeMessages`.
- The target contract exceeded the specified `gasLimit` while executing `receiveWormholeMessages`.
All three of these scenarios can be avoided with correct design by the integrator, and thus, it is up to the integrator to resolve them. Any other scenario that causes a delivery to not be performed should be considered an outage by some component of the system, including potentially the blockchains themselves.
`Forward Request Success` and `Forward Failure` represent when the delivery succeeded and the user requested a forward during the delivery. If the user has enough funds left over as a refund to complete the forward, the forward will be executed, and the status will be `Forward Request Success`. Otherwise, it will be `Forward Request Failure`.
## Other Considerations
Some implementation details should be considered during development to ensure safety and a pleasant UX. Ensure that your engineering efforts have appropriately considered each of the following areas:
- Receiving a message from a relayer.
- Checking for expected emitter.
- Calling `parseAndVerify` on any additional VAAs.
- Replay protection.
- Message ordering (no guarantees on order of messages delivered).
- Forwarding and call chaining.
- Refunding overpayment of `gasLimit`.
- Refunding overpayment of value sent.
## Track the Progress of Messages with the Wormhole CLI
While no off-chain programs are required, a developer may want to track the progress of messages in flight. To track the progress of messages in flight, use the [Wormhole CLI](/docs/tools/cli/get-started/){target=\_blank} tool's `status` subcommand. As an example, you can use the following commands to track the status of a transfer by providing the environment, origin network, and transaction hash to the `worm status` command:
=== "Mainnet"
```bash
worm status mainnet ethereum INSERT_TRANSACTION_HASH
```
=== "Testnet"
```bash
worm status testnet ethereum INSERT_TRANSACTION_HASH
```
See the [Wormhole CLI tool docs](/docs/tools/cli/get-started/){target=\_blank} for installation and usage.
## Step-by-Step Tutorial
For detailed, step-by-step guidance on creating cross-chain contracts that interact with the Wormhole relayer, refer to the [Create Cross-Chain Contracts](/docs/products/messaging/tutorials/cross-chain-contracts/) tutorial.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/cross-chain-contracts.md
--- BEGIN CONTENT ---
---
title: Create Cross-Chain Contracts
description: Learn how to create cross-chain contracts using Wormhole's Solidity SDK. Deploy contracts on Avalanche and Celo Testnets and send messages across chains.
categories: Basics
---
# Create Cross-Chain Messaging Contracts
:simple-github: [Source code on GitHub](https://github.com/wormhole-foundation/demo-wormhole-messaging){target=\_blank}
Wormhole's cross-chain messaging allows smart contracts to interact seamlessly across multiple blockchains. This enables developers to build decentralized applications that leverage the strengths of different networks, whether it's Avalanche, Celo, Ethereum, or beyond. In this tutorial, we'll explore using [Wormhole's Solidity SDK](https://github.com/wormhole-foundation/wormhole-solidity-sdk){target=\_blank} to create cross-chain contracts to send and receive messages across chains.
Wormhole's messaging infrastructure simplifies data transmission, event triggering, and transaction initiation across blockchains. In this tutorial, we'll guide you through a simple yet powerful hands-on demonstration that showcases this practical capability. We'll deploy contracts on two Testnets—Avalanche Fuji and Celo Alfajores—and send messages from one chain to another. This tutorial is perfect for those new to cross-chain development and seeking hands-on experience with Wormhole's powerful toolkit.
By the end of this tutorial, you will have not only built a fully functioning cross-chain message sender and receiver using Solidity but also developed a comprehensive understanding of how to interact with the Wormhole relayer, manage cross-chain costs, and ensure your smart contracts are configured correctly on both source and target chains.
This tutorial assumes a basic understanding of Solidity and smart contract development. Before diving in, it may be helpful to review [the basics of Wormhole](/docs/protocol/introduction/){target=\_blank} to familiarize yourself with the protocol.
## Wormhole Overview
We'll interact with two key Wormhole components: the [Wormhole relayer](/docs/protocol/infrastructure/relayer/){target=\_blank} and the [Wormhole Core Contracts](/docs/protocol/infrastructure/core-contracts/){target=\_blank}. The relayer handles cross-chain message delivery and ensures the message is accurately received on the target chain. This allows smart contracts to communicate across blockchains without developers worrying about the underlying complexity.
Additionally, we'll rely on the Wormhole relayer to automatically determine cross-chain transaction costs and facilitate payments. This feature simplifies cross-chain development by allowing you to specify only the target chain and the message. The relayer handles the rest, ensuring that the message is transmitted with the appropriate fee.

## Prerequisites
Before starting this tutorial, ensure you have the following:
- [Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm){target=\_blank} installed on your machine.
- [Foundry](https://getfoundry.sh/introduction/installation/){target=\_blank} for deploying contracts.
- Testnet tokens for [Avalanche-Fuji](https://core.app/tools/testnet-faucet/?token=C){target=\_blank} and [Celo-Alfajores](https://faucet.celo.org/alfajores){target=\_blank} to cover gas fees.
- Wallet private key.
## Build Cross-Chain Messaging Contracts
In this section, we'll deploy two smart contracts: one to send a message from Avalanche Fuji and another to receive it on Celo Alfajores. The contracts interact with the Wormhole relayer to transmit messages across chains.
At a high level, our contracts will:
1. Send a message from Avalanche to Celo using the Wormhole relayer.
2. Receive and process the message on Celo, logging the content of the message.
Before diving into the deployment steps, let's first break down key parts of the contracts.
### Sender Contract: MessageSender
The `MessageSender` contract is responsible for quoting the cost of sending a message cross-chain and then sending that message.
Key functions include:
- **`quoteCrossChainCost`**: Calculates the cost of delivering a message to the target chain using the Wormhole relayer.
- **`sendMessage`**: Encodes the message and sends it to the target chain and contract address using the Wormhole relayer.
Here's the core of the contract:
```solidity
uint16 targetChain,
address targetAddress,
string memory message
) external payable {
uint256 cost = quoteCrossChainCost(targetChain);
require(
msg.value >= cost,
"Insufficient funds for cross-chain delivery"
);
wormholeRelayer.sendPayloadToEvm{value: cost}(
targetChain,
targetAddress,
abi.encode(message, msg.sender),
0,
GAS_LIMIT
);
}
```
You can find the full code for the `MessageSender.sol` below.
??? code "MessageSender.sol"
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;
import "lib/wormhole-solidity-sdk/src/interfaces/IWormholeRelayer.sol";
contract MessageSender {
IWormholeRelayer public wormholeRelayer;
uint256 constant GAS_LIMIT = 50000;
constructor(address _wormholeRelayer) {
wormholeRelayer = IWormholeRelayer(_wormholeRelayer);
}
function quoteCrossChainCost(
uint16 targetChain
) public view returns (uint256 cost) {
(cost, ) = wormholeRelayer.quoteEVMDeliveryPrice(
targetChain,
0,
GAS_LIMIT
);
}
function sendMessage(
uint16 targetChain,
address targetAddress,
string memory message
) external payable {
uint256 cost = quoteCrossChainCost(targetChain);
require(
msg.value >= cost,
"Insufficient funds for cross-chain delivery"
);
wormholeRelayer.sendPayloadToEvm{value: cost}(
targetChain,
targetAddress,
abi.encode(message, msg.sender),
0,
GAS_LIMIT
);
}
}
```
### Receiver Contract: MessageReceiver
The `MessageReceiver` contract handles incoming cross-chain messages. When a message arrives, it decodes the payload and logs the message content. It ensures that only authorized contracts can send and process messages, adding an extra layer of security in cross-chain communication.
#### Emitter Validation and Registration
In cross-chain messaging, validating the sender is essential to prevent unauthorized contracts from sending messages. The `isRegisteredSender` modifier ensures that messages can only be processed if they come from the registered contract on the source chain. This guards against malicious messages and enhances security.
Key implementation details include:
- **`registeredSender`**: Stores the address of the registered sender contract.
- **`setRegisteredSender`**: Registers the sender's contract address on the source chain. It ensures that only registered contracts can send messages, preventing unauthorized senders.
- **`isRegisteredSender`**: Restricts the processing of messages to only those from registered senders, preventing unauthorized cross-chain communication.
```solidity
require(
registeredSenders[sourceChain] == sourceAddress,
"Not registered sender"
);
_;
}
function setRegisteredSender(
uint16 sourceChain,
bytes32 sourceAddress
) public {
require(
msg.sender == registrationOwner,
"Not allowed to set registered sender"
);
registeredSenders[sourceChain] = sourceAddress;
}
```
#### Message Processing
The `receiveWormholeMessages` is the core function that processes the received message. It checks that the Wormhole relayer sent the message, decodes the payload, and emits an event with the message content. It is essential to verify the message sender to prevent unauthorized messages.
```solidity
bytes memory payload,
bytes[] memory,
bytes32 sourceAddress,
uint16 sourceChain,
bytes32
) public payable override isRegisteredSender(sourceChain, sourceAddress) {
require(
msg.sender == address(wormholeRelayer),
"Only the Wormhole relayer can call this function"
);
// Decode the payload to extract the message
string memory message = abi.decode(payload, (string));
// Example use of sourceChain for logging
if (sourceChain != 0) {
emit SourceChainLogged(sourceChain);
}
// Emit an event with the received message
emit MessageReceived(message);
}
```
You can find the full code for the `MessageReceiver.sol` below.
??? code "MessageReceiver.sol"
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.18;
import "lib/wormhole-solidity-sdk/src/interfaces/IWormholeRelayer.sol";
import "lib/wormhole-solidity-sdk/src/interfaces/IWormholeReceiver.sol";
contract MessageReceiver is IWormholeReceiver {
IWormholeRelayer public wormholeRelayer;
address public registrationOwner;
// Mapping to store registered senders for each chain
mapping(uint16 => bytes32) public registeredSenders;
event MessageReceived(string message);
event SourceChainLogged(uint16 sourceChain);
constructor(address _wormholeRelayer) {
wormholeRelayer = IWormholeRelayer(_wormholeRelayer);
registrationOwner = msg.sender; // Set contract deployer as the owner
}
modifier isRegisteredSender(uint16 sourceChain, bytes32 sourceAddress) {
require(
registeredSenders[sourceChain] == sourceAddress,
"Not registered sender"
);
_;
}
function setRegisteredSender(
uint16 sourceChain,
bytes32 sourceAddress
) public {
require(
msg.sender == registrationOwner,
"Not allowed to set registered sender"
);
registeredSenders[sourceChain] = sourceAddress;
}
// Update receiveWormholeMessages to include the source address check
function receiveWormholeMessages(
bytes memory payload,
bytes[] memory,
bytes32 sourceAddress,
uint16 sourceChain,
bytes32
) public payable override isRegisteredSender(sourceChain, sourceAddress) {
require(
msg.sender == address(wormholeRelayer),
"Only the Wormhole relayer can call this function"
);
// Decode the payload to extract the message
string memory message = abi.decode(payload, (string));
// Example use of sourceChain for logging
if (sourceChain != 0) {
emit SourceChainLogged(sourceChain);
}
// Emit an event with the received message
emit MessageReceived(message);
}
}
```
## Deploy Contracts
This section will guide you through deploying the cross-chain messaging contracts on the Avalanche Fuji and Celo Alfajores Testnets. Follow these steps to get your contracts up and running.
### Deployment Tools
We use _Foundry_ to deploy our smart contracts. However, you can use any tool you're comfortable with, such as:
- [Remix](https://remix.ethereum.org/){target=\_blank} for a browser-based IDE.
- [Hardhat](https://hardhat.org/hardhat-runner/docs/getting-started#installation){target=\_blank} for a more extensive JavaScript/TypeScript workflow.
- [Foundry](https://getfoundry.sh/introduction/installation/){target=\_blank} for a CLI-focused experience with built-in scripting and testing features.
The contracts and deployment steps remain the same regardless of your preferred tool. The key is to ensure you have the necessary Testnet funds and are deploying to the right networks.
### Repository Setup
To get started with cross-chain messaging using Wormhole, first clone the [GitHub repository](https://github.com/wormhole-foundation/demo-wormhole-messaging){target=\_blank}. This repository includes everything you need to deploy, interact, and test the message flow between chains.
This demo focuses on using the scripts, so it's best to take a look at them, starting with `deploySender.ts`, `deployReceiver.ts`, and `sendMessage.ts`.
To configure the dependencies properly, run the following command:
```bash
npm install
```
The repository includes:
- Two Solidity contracts:
- **`MessageSender.sol`**: Contract that sends the cross-chain message from Avalanche.
- **`MessageReceiver.sol`**: Contract that receives the cross-chain message on Celo.
- Deployment scripts located in the `script` directory:
- **`deploySender.ts`**: Deploys the `MessageSender` contract to Avalanche.
- **`deployReceiver.ts`**: Deploys the `MessageReceiver` contract to Celo.
- **`sendMessage.ts`**: Sends a message from Avalanche to Celo.
- Configuration files and ABI JSON files for easy deployment and interaction:
- **`chains.json`**: Configuration file that stores key information for the supported Testnets, including the Wormhole relayer addresses, RPC URLs, and chain IDs. You likely won't need to modify this file unless you're working with different networks.
- A dedicated `interfaces` directory inside the `src` folder for TypeScript type definitions:
- **`ChainsConfig.ts`**: Defines the types for the `chains.json` configuration file.
- **`DeployedContracts.ts`**: Contains types for deployed contract addresses and related information.
- **`MessageJsons.ts`**: Includes types for ABI and bytecode JSONs used by the deployment scripts.
- **`index.ts`**: Serves as an export aggregator for the interfaces, simplifying imports in other files.
### Important Setup Steps
1. **Add your private key**: Create a `.env` file in the root of the project and add your private key.
```env
touch .env
```
Inside `.env`, add your private key in the following format:
```env
PRIVATE_KEY=INSERT_PRIVATE_KEY
```
2. **Compile the contracts**: Ensure everything is set up correctly by compiling the contracts.
```bash
forge build
```
The expected output should be similar to this:
forge build > [⠒] Compiling... > [⠰] Compiling 30 files with 0.8.23 [⠔] Solc 0.8.23 finished in 2.29sCompiler run successful!
### Deployment Process
Both deployment scripts, `deploySender.ts` and `deployReceiver.ts`, perform the following key tasks:
1. **Load configuration and contract details**: Each script begins by loading the necessary configuration details, such as the network's RPC URL and the contract's ABI and bytecode. This information is essential for deploying the contract to the correct blockchain network.
=== "`chains.json`"
```json
{
"chains": [
{
"description": "Avalanche testnet fuji",
"chainId": 6,
"rpc": "https://api.avax-test.network/ext/bc/C/rpc",
"tokenBridge": "0x61E44E506Ca5659E6c0bba9b678586fA2d729756",
"wormholeRelayer": "0xA3cF45939bD6260bcFe3D66bc73d60f19e49a8BB",
"wormhole": "0x7bbcE28e64B3F8b84d876Ab298393c38ad7aac4C"
},
{
"description": "Celo Testnet",
"chainId": 14,
"rpc": "https://alfajores-forno.celo-testnet.org",
"tokenBridge": "0x05ca6037eC51F8b712eD2E6Fa72219FEaE74E153",
"wormholeRelayer": "0x306B68267Deb7c5DfCDa3619E22E9Ca39C374f84",
"wormhole": "0x88505117CA88e7dd2eC6EA1E13f0948db2D50D56"
}
]
}
```
=== "`deploySender.ts`"
```typescript
const chains: ChainsConfig = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
// Get the Avalanche Fuji configuration
const avalancheChain = chains.chains.find((chain) =>
chain.description.includes('Avalanche testnet')
);
```
=== "`deployReceiver.ts`"
```typescript
const chains: ChainsConfig = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
// Get the Celo Testnet configuration
const celoChain = chains.chains.find((chain) =>
chain.description.includes('Celo Testnet')
);
```
!!! note
The `chains.json` file contains the configuration details for the Avalanche Fuji and Celo Alfajores Testnets. You can modify this file to add more networks if needed. For a complete list of contract addresses, visit the [reference page](/docs/products/reference/contract-addresses/){target=\_blank}.
2. **Set up provider and wallet**: The scripts establish a connection to the blockchain using a provider and create a wallet instance using a private key. This wallet is responsible for signing the deployment transaction.
=== "`deploySender.ts`"
```typescript
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
```
=== "`deployReceiver.ts`"
```typescript
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
```
3. **Deploy the contract**: The contract is deployed to the network specified in the configuration. Upon successful deployment, the contract address is returned, which is crucial for interacting with the contract later on.
=== "`deploySender.ts`"
```typescript
avalancheChain.wormholeRelayer
);
await senderContract.waitForDeployment();
```
=== "`deployReceiver.ts`"
```typescript
celoChain.wormholeRelayer
);
await receiverContract.waitForDeployment();
```
4. **Register the `MessageSender` on the target chain**: After you deploy the `MessageReceiver` contract on the Celo Alfajores network, the sender contract address from Avalanche Fuji needs to be registered. This ensures that only messages from the registered `MessageSender` contract are processed.
This additional step is essential to enforce emitter validation, preventing unauthorized senders from delivering messages to the `MessageReceiver` contract
```typescript
const avalancheSenderAddress = deployedContracts.avalanche?.MessageSender;
if (!avalancheSenderAddress) {
throw new Error('Avalanche MessageSender address not found.');
}
// Define the source chain ID for Avalanche Fuji
const sourceChainId = 6;
// Call setRegisteredSender on the MessageReceiver contract
const tx = await (receiverContract as any).setRegisteredSender(
sourceChainId,
ethers.zeroPadValue(avalancheSenderAddress, 32)
);
await tx.wait();
```
You can find the full code for the `deploySender.ts` and `deployReceiver.ts` below.
??? code "deploySender.ts"
```typescript
import { ethers } from 'ethers';
import fs from 'fs';
import path from 'path';
import dotenv from 'dotenv';
import {
ChainsConfig,
DeployedContracts,
MessageSenderJson,
} from './interfaces';
dotenv.config();
async function main(): Promise {
// Load the chain configuration from JSON
const chains: ChainsConfig = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
// Get the Avalanche Fuji configuration
const avalancheChain = chains.chains.find((chain) =>
chain.description.includes('Avalanche testnet')
);
if (!avalancheChain) {
throw new Error(
'Avalanche testnet configuration not found in chains.json.'
);
}
// Set up the provider and wallet
const provider = new ethers.JsonRpcProvider(avalancheChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
// Load the ABI and bytecode of the MessageSender contract
const messageSenderJson: MessageSenderJson = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../out/MessageSender.sol/MessageSender.json'),
'utf8'
)
);
const { abi, bytecode } = messageSenderJson;
// Create a ContractFactory for MessageSender
const MessageSender = new ethers.ContractFactory(abi, bytecode, wallet);
// Deploy the contract using the Wormhole Relayer address for Avalanche Fuji
const senderContract = await MessageSender.deploy(
avalancheChain.wormholeRelayer
);
await senderContract.waitForDeployment();
console.log('MessageSender deployed to:', senderContract.target); // `target` is the address in ethers.js v6
// Update the deployedContracts.json file
const deployedContractsPath = path.resolve(
__dirname,
'../deploy-config/deployedContracts.json'
);
const deployedContracts: DeployedContracts = JSON.parse(
fs.readFileSync(deployedContractsPath, 'utf8')
);
deployedContracts.avalanche = {
MessageSender: senderContract.target as any,
deployedAt: new Date().toISOString(),
};
fs.writeFileSync(
deployedContractsPath,
JSON.stringify(deployedContracts, null, 2)
);
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
??? code "deployReceiver.ts"
```typescript
import { ethers } from 'ethers';
import fs from 'fs';
import path from 'path';
import dotenv from 'dotenv';
import {
ChainsConfig,
DeployedContracts,
MessageReceiverJson,
} from './interfaces';
dotenv.config();
async function main(): Promise {
// Load the chain configuration from the JSON file
const chains: ChainsConfig = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
// Get the Celo Testnet configuration
const celoChain = chains.chains.find((chain) =>
chain.description.includes('Celo Testnet')
);
if (!celoChain) {
throw new Error('Celo Testnet configuration not found.');
}
// Set up the provider and wallet
const provider = new ethers.JsonRpcProvider(celoChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
// Load the ABI and bytecode of the MessageReceiver contract
const messageReceiverJson: MessageReceiverJson = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/MessageReceiver.sol/MessageReceiver.json'
),
'utf8'
)
);
const { abi, bytecode } = messageReceiverJson;
// Create a ContractFactory for MessageReceiver
const MessageReceiver = new ethers.ContractFactory(abi, bytecode, wallet);
// Deploy the contract using the Wormhole Relayer address for Celo Testnet
const receiverContract = await MessageReceiver.deploy(
celoChain.wormholeRelayer
);
await receiverContract.waitForDeployment();
console.log('MessageReceiver deployed to:', receiverContract.target); // `target` is the contract address in ethers.js v6
// Update the deployedContracts.json file
const deployedContractsPath = path.resolve(
__dirname,
'../deploy-config/deployedContracts.json'
);
const deployedContracts: DeployedContracts = JSON.parse(
fs.readFileSync(deployedContractsPath, 'utf8')
);
// Retrieve the address of the MessageSender from the deployedContracts.json file
const avalancheSenderAddress = deployedContracts.avalanche?.MessageSender;
if (!avalancheSenderAddress) {
throw new Error('Avalanche MessageSender address not found.');
}
// Define the source chain ID for Avalanche Fuji
const sourceChainId = 6;
// Call setRegisteredSender on the MessageReceiver contract
const tx = await (receiverContract as any).setRegisteredSender(
sourceChainId,
ethers.zeroPadValue(avalancheSenderAddress, 32)
);
await tx.wait();
console.log(
`Registered MessageSender (${avalancheSenderAddress}) for Avalanche chain (${sourceChainId})`
);
deployedContracts.celo = {
MessageReceiver: receiverContract.target as any,
deployedAt: new Date().toISOString(),
};
fs.writeFileSync(
deployedContractsPath,
JSON.stringify(deployedContracts, null, 2)
);
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
### Deploy the Sender Contract
The sender contract will handle quoting and sending messages cross-chain.
1. Run the following command to deploy the sender contract:
```bash
npm run deploy:sender
```
2. Once deployed, the contract address will be displayed. You may check the contract on the [Avalanche Fuji Explorer](https://testnet.snowtrace.io/){target=\_blank}.
npm run deploy:sender > wormhole-cross-chain@1.0.0 deploy:sender > node script/deploySender.ts MessageSender deployed to: 0xf5c474f335fFf617fA6FD04DCBb17E20ee0cEfb1
### Deploy the Receiver Contract
The receiver contract listens for cross-chain messages and logs them when received.
1. Deploy the receiver contract with this command:
```bash
npm run deploy:receiver
```
2. After deployment, note down the contract address. You may check the contract on the [Celo Alfajores Explorer](https://alfajores.celoscan.io/){target=\_blank}.
## Send a Cross-Chain Message
Now that both the sender and receiver contracts are deployed, let's move on to the next exciting step: sending a cross-chain message from Avalanche Fuji to Celo Alfajores.
In this example, we will use the `sendMessage.ts` script to transmit a message from the sender contract on Avalanche to the receiver contract on Celo. The script uses [Ethers.js](https://docs.ethers.org/v6/){target=\_blank} to interact with the deployed contracts, calculate the cross-chain cost dynamically, and handle the transaction.
Let's break down the script step by step.
1. **Load configuration files**:
1. **`chains.json`**: Contains details about the supported Testnet chains, such as RPC URLs and relayer addresses.
2. **`deployedContracts.json`**: Stores the addresses of the deployed sender and receiver contracts. This file is dynamically updated when contracts are deployed, but users can also manually add their own deployed contract addresses if needed.
```typescript
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
const deployedContracts: DeployedContracts = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/deployedContracts.json'),
'utf8'
)
);
```
2. **Configure the provider and signer**: The script first reads the chain configurations and extracts the contract addresses. One essential step in interacting with a blockchain is setting up a _provider_. A provider is your connection to the blockchain network. It allows your script to interact with the blockchain, retrieve data, and send transactions. In this case, we're using a JSON-RPC provider.
Next, we configure the wallet, which will be used to sign transactions. The wallet is created using the private key and the provider. This ensures that all transactions sent from this wallet are broadcast to the Avalanche Fuji network.
```typescript
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
```
After setting up the wallet, the script loads the ABI for the `MessageSender.sol` contract and creates an instance of it.
```typescript
fs.readFileSync(
path.resolve(__dirname, '../out/MessageSender.sol/MessageSender.json'),
'utf8'
)
);
```
3. **Set up the message details**: The next part of the script defines the target chain (Celo) and the target address (the receiver contract on Celo).
```typescript
const targetAddress = deployedContracts.celo.MessageReceiver;
```
You can customize the message that will be sent across chains.
```typescript
```
4. **Estimate cross-chain cost**: Before sending the message, we dynamically calculate the cross-chain cost using the `quoteCrossChainCost` function.
```typescript
```
This ensures that the transaction includes enough funds to cover the gas fees for the cross-chain message.
5. **Send a message**: With everything set up, the message is sent using the `sendMessage` function.
```typescript
targetChain,
targetAddress,
message,
{
value: txCost,
}
);
```
After sending, the script waits for the transaction to be confirmed.
```typescript
```
6. **Run the script**: To send the message, run the following command:
```bash
npm run send:message
```
If everything is set up correctly, the message will be sent from the Avalanche Fuji Testnet to the Celo Alfajores Testnet. You can monitor the transaction and verify that the message was received on Celo using the [Wormhole Explorer](https://wormholescan.io/#/?network=TESTNET){target=\_blank}.
The console should output something similar to this:
npm run send:message > wormhole-cross-chain@1.0.0 send:message > node script/sendMessage.tsSender Contract Address: 0xD720BFF42a0960cfF1118454A907a44dB358f2b1Receiver Contract Address: 0x692550997C252cC5044742D1A2BD91E4f4b46D39...Transaction sent, waiting for confirmation......Message sent! Transaction hash:
0x9d359a66ba42baced80062229c0b02b4f523fe304aff3473dcf53117aee13fb6You may see the transaction status on the Wormhole Explorer:
https://wormholescan.io/#/tx/0x9d359a66ba42baced80062229c0b02b4f523fe304aff3473dcf53117aee13fb6?network=TESTNET
You can find the full code for the `sendMessage.ts` below.
??? code "sendMessage.ts"
```solidity
import { ethers } from 'ethers';
import fs from 'fs';
import path from 'path';
import dotenv from 'dotenv';
import { ChainsConfig, DeployedContracts } from './interfaces';
dotenv.config();
async function main(): Promise {
// Load the chain configuration and deployed contract addresses
const chains: ChainsConfig = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/chains.json'),
'utf8'
)
);
const deployedContracts: DeployedContracts = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../deploy-config/deployedContracts.json'),
'utf8'
)
);
console.log(
'Sender Contract Address: ',
deployedContracts.avalanche.MessageSender
);
console.log(
'Receiver Contract Address: ',
deployedContracts.celo.MessageReceiver
);
console.log('...');
// Get the Avalanche Fuji configuration
const avalancheChain = chains.chains.find((chain) =>
chain.description.includes('Avalanche testnet')
);
if (!avalancheChain) {
throw new Error(
'Avalanche testnet configuration not found in chains.json.'
);
}
// Set up the provider and wallet
const provider = new ethers.JsonRpcProvider(avalancheChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
// Load the ABI of the MessageSender contract
const messageSenderJson = JSON.parse(
fs.readFileSync(
path.resolve(__dirname, '../out/MessageSender.sol/MessageSender.json'),
'utf8'
)
);
const abi = messageSenderJson.abi;
// Create a contract instance for MessageSender
const MessageSender = new ethers.Contract(
deployedContracts.avalanche.MessageSender, // Automatically use the deployed address
abi,
wallet
);
// Define the target chain and target address (the Celo receiver contract)
const targetChain = 14; // Wormhole chain ID for Celo Alfajores
const targetAddress = deployedContracts.celo.MessageReceiver;
// The message you want to send
const message = 'Hello from Avalanche to Celo!';
// Dynamically quote the cross-chain cost
const txCost = await MessageSender.quoteCrossChainCost(targetChain);
// Send the message (make sure to send enough gas in the transaction)
const tx = await MessageSender.sendMessage(
targetChain,
targetAddress,
message,
{
value: txCost,
}
);
console.log('Transaction sent, waiting for confirmation...');
await tx.wait();
console.log('...');
console.log('Message sent! Transaction hash:', tx.hash);
console.log(
`You may see the transaction status on the Wormhole Explorer: https://wormholescan.io/#/tx/${tx.hash}?network=TESTNET`
);
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
## Conclusion
You're now fully equipped to build cross-chain contracts using the Wormhole protocol! With this tutorial, you've learned how to:
- Deploy sender and receiver contracts on different testnets.
- Send a cross-chain message from one blockchain to another.
- Monitor the status of your cross-chain transactions using Wormholescan and the Wormhole Solidity SDK.
Looking for more? Check out the [Wormhole Tutorial Demo repository](https://github.com/wormhole-foundation/demo-tutorials){target=\_blank} for additional examples.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/cross-chain-token-contracts.md
--- BEGIN CONTENT ---
---
title: Cross-Chain Token Transfers
description: Learn how to create cross-chain token transfers using Wormhole's Solidity SDK. Build and deploy smart contracts to send tokens from one blockchain to another.
categories: Basics
---
# Create Cross-Chain Token Transfer Contracts
:simple-github: [Source code on GitHub](https://github.com/wormhole-foundation/demo-cross-chain-token-transfer){target=\_blank}
In this tutorial, you'll learn how to create a simple cross-chain token transfer system using the Wormhole protocol via the [Wormhole Solidity SDK](https://github.com/wormhole-foundation/wormhole-solidity-sdk){target=\_blank}. We'll guide you through building and deploying smart contracts that enable seamless token transfers of IERC-20 tokens between blockchains. Whether you're a developer looking to explore cross-chain applications or just interested in the Wormhole protocol, this guide will help you understand the fundamentals.
By the end of this tutorial, you'll have a working cross-chain token transfer system built with the powerful tools provided by the Wormhole Solidity SDK, which you can further customize and integrate into your projects.
## Prerequisites
Before you begin, ensure you have the following:
- [Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm){target=\_blank} installed on your machine.
- [Foundry](https://getfoundry.sh/introduction/installation/){target=\_blank} for deploying contracts.
- Testnet tokens for [Avalanche-Fuji](https://core.app/tools/testnet-faucet/?token=C){target=\_blank} and [Celo-Alfajores](https://faucet.celo.org/alfajores){target=\_blank} to cover gas fees.
- [USDC Testnet](https://faucet.circle.com/){target=\_blank} tokens on Avalanche-Fuji or/and Celo-Alfajores for cross-chain transfer.
- Wallet private key.
## Valid Tokens for Transfer
It's important to note that this tutorial leverages [Wormhole's TokenBridge](https://github.com/wormhole-foundation/wormhole/blob/6130bbb6f456b42b789a71f7ea2fd049d632d2fb/ethereum/contracts/bridge/TokenBridge.sol){target=\_blank} to transfer tokens between chains. So, the tokens you'd like to transfer must have an attestation on the `TokenBridge` contract of the target blockchain.
To simplify this process, we've included a tool for verifying if a token has an attestation on the target chain. This tool uses the [`wrappedAsset`](https://github.com/wormhole-foundation/wormhole/blob/6130bbb6f456b42b789a71f7ea2fd049d632d2fb/ethereum/contracts/bridge/BridgeGetters.sol#L50-L52){target=\_blank} function from the `TokenBridge` contract. If the token has an attestation, the `wrappedAsset` function returns the address of the wrapped token on the target chain; otherwise, it returns the zero address.
???- tip "Check Token Attestation"
1. Clone the [repository](https://github.com/wormhole-foundation/demo-cross-chain-token-transfer){target=\_blank} and navigate to the project directory:
```bash
git clone https://github.com/wormhole-foundation/demo-cross-chain-token-transfer.git
cd cross-chain-token-transfers
```
2. Install the dependencies:
```bash
npm install
```
3. Run the script to check token attestation:
```bash
npm run verify
```
4. Follow the prompts:
1. Enter the RPC URL of the target chain.
2. Enter the `TokenBridge` contract address on the target chain.
3. Enter the token contract address on the source chain.
4. Enter the source chain ID.
5. The expected output when the token has an attestation:
npm run verify > cross-chain-token-transfer@1.0.0 verify > npx ts-node script/check-attestation.ts Enter the TARGET chain RPC URL: https://alfajores-forno.celo-testnet.org Enter the WTT contract address on the TARGET chain: 0x05...E153 Enter the token contract address on the SOURCE chain: 0x54...bc65 Enter the SOURCE chain ID: 6 The token is attested on the target chain. Wrapped token address: 0xDDB349c976cA2C873644F21f594767Eb5390C831
Using this tool ensures that you only attempt to transfer tokens with verified attestations, avoiding any potential issues during the cross-chain transfer process.
## Project Setup
Let's start by initializing a new Foundry project. This will set up a basic structure for our smart contracts.
1. Open your terminal and run the following command to initialize a new Foundry project:
```bash
forge init cross-chain-token-transfers
```
This will create a new directory named `cross-chain-token-transfers` with a basic project structure. This also initializes a new `git` repository.
2. Navigate into the newly created project directory:
```bash
cd cross-chain-token-transfers
```
3. Install the Wormhole Solidity SDK:
```bash
forge install wormhole-foundation/wormhole-solidity-sdk
```
To ease development, we'll use the Wormhole Solidity SDK, which provides useful helpers for cross-chain development.
This SDK includes the `TokenSender` and `TokenReceiver` abstract classes, which simplify sending and receiving tokens across chains.
## Build Cross-Chain Contracts
In this section, we'll build two smart contracts to send tokens from a source chain and receive them on a target chain. These contracts will interact with the Wormhole protocol to facilitate secure and seamless cross-chain token transfers.
At a high level, our contracts will:
1. Send tokens from one blockchain to another using the Wormhole protocol.
2. Receive and process the tokens on the target chain, ensuring they are correctly transferred to the intended recipient.
Before diving into the contract implementation steps, let’s first break down the key parts of the contracts.
### Sender Contract: CrossChainSender
The `CrossChainSender` contract calculates the cost of sending tokens across chains and then facilitates the actual token transfer.
Let's start writing the `CrossChainSender` contract:
1. Create a new file named `CrossChainSender.sol` in the `/src` directory:
```bash
touch src/CrossChainSender.sol
```
2. Open the file. First, we'll start with the imports and the contract setup:
```solidity
pragma solidity ^0.8.13;
import "lib/wormhole-solidity-sdk/src/WormholeRelayerSDK.sol";
import "lib/wormhole-solidity-sdk/src/interfaces/IERC20.sol";
contract CrossChainSender is TokenSender {
uint256 constant GAS_LIMIT = 250_000;
constructor(
address _wormholeRelayer,
address _tokenBridge,
address _wormhole
) TokenBase(_wormholeRelayer, _tokenBridge, _wormhole) {}
```
This sets up the basic structure of the contract, including the necessary imports and the constructor that initializes the contract with the Wormhole-related addresses.
With the contract structure in place, define the following functions within its body to enable multichain token transfers.
3. Next, let's add a function that estimates the cost of sending tokens across chains:
```solidity
uint16 targetChain
) public view returns (uint256 cost) {
uint256 deliveryCost;
(deliveryCost, ) = wormholeRelayer.quoteEVMDeliveryPrice(
targetChain,
0,
GAS_LIMIT
);
cost = deliveryCost + wormhole.messageFee();
}
```
This function, `quoteCrossChainDeposit`, helps calculate the cost of transferring tokens to a different chain. It factors in the delivery cost and the cost of publishing a message via the Wormhole protocol.
4. Finally, we'll add the function that sends the tokens across chains:
```solidity
uint16 targetChain,
address targetReceiver,
address recipient,
uint256 amount,
address token
) public payable {
uint256 cost = quoteCrossChainDeposit(targetChain);
require(
msg.value == cost,
"msg.value must equal quoteCrossChainDeposit(targetChain)"
);
IERC20(token).transferFrom(msg.sender, address(this), amount);
bytes memory payload = abi.encode(recipient);
sendTokenWithPayloadToEvm(
targetChain,
targetReceiver,
payload,
0,
GAS_LIMIT,
token,
amount
);
}
```
This `sendCrossChainDeposit` function is where the actual token transfer happens. It sends the tokens to the recipient on the target chain using the Wormhole protocol.
Here’s a breakdown of what happens in each step of the `sendCrossChainDeposit` function:
1. **Cost calculation**: The function starts by calculating the cost of the cross-chain transfer using `quoteCrossChainDeposit`(`targetChain`). This cost includes both the delivery fee and the Wormhole message fee. The `sendCrossChainDeposit` function then checks that the user has sent the correct amount of Ether to cover this cost (`msg.value`).
2. **Token transfer to contract**: The next step is to transfer the specified amount of tokens from the user to the contract itself using `IERC-20(token).transferFrom(msg.sender, address(this), amount)`. This ensures that the contract has custody of the tokens before initiating the cross-chain transfer.
3. **Payload encoding**: The recipient's address on the target chain is encoded into a payload using `abi.encode(recipient)`. This payload will be sent along with the token transfer, so the target contract knows who should receive the tokens on the destination chain.
4. **Cross-chain transfer**: The `sendTokenWithPayloadToEvm` function is called to initiate the cross-chain token transfer. This function does the following:
- Specifies the `targetChain` (the Wormhole chain ID of the destination blockchain).
- Sends the `targetReceiver` contract address on the target chain that will receive the tokens.
- Attaches the payload containing the recipient's address.
- Sets the `GAS_LIMIT` for the transaction.
- Passes the token `address` and `amount` to transfer.
This triggers the Wormhole protocol to handle the cross-chain messaging and token transfer, ensuring the tokens and payload reach the correct destination on the target chain.
You can find the complete code for the `CrossChainSender.sol` below.
??? code "MessageSender.sol"
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;
import "lib/wormhole-solidity-sdk/src/WormholeRelayerSDK.sol";
import "lib/wormhole-solidity-sdk/src/interfaces/IERC20.sol";
contract CrossChainSender is TokenSender {
uint256 constant GAS_LIMIT = 250_000;
constructor(
address _wormholeRelayer,
address _tokenBridge,
address _wormhole
) TokenBase(_wormholeRelayer, _tokenBridge, _wormhole) {}
// Function to get the estimated cost for cross-chain deposit
function quoteCrossChainDeposit(
uint16 targetChain
) public view returns (uint256 cost) {
uint256 deliveryCost;
(deliveryCost, ) = wormholeRelayer.quoteEVMDeliveryPrice(
targetChain,
0,
GAS_LIMIT
);
cost = deliveryCost + wormhole.messageFee();
}
// Function to send tokens and payload across chains
function sendCrossChainDeposit(
uint16 targetChain,
address targetReceiver,
address recipient,
uint256 amount,
address token
) public payable {
uint256 cost = quoteCrossChainDeposit(targetChain);
require(
msg.value == cost,
"msg.value must equal quoteCrossChainDeposit(targetChain)"
);
IERC20(token).transferFrom(msg.sender, address(this), amount);
bytes memory payload = abi.encode(recipient);
sendTokenWithPayloadToEvm(
targetChain,
targetReceiver,
payload,
0,
GAS_LIMIT,
token,
amount
);
}
}
```
### Receiver Contract: CrossChainReceiver
The `CrossChainReceiver` contract is designed to handle the receipt of tokens and payloads from another blockchain. It ensures that the tokens are correctly transferred to the designated recipient on the receiving chain.
Let's start writing the `CrossChainReceiver` contract:
1. Create a new file named `CrossChainReceiver.sol` in the `/src` directory:
```bash
touch src/CrossChainReceiver.sol
```
2. Open the file. First, we'll start with the imports and the contract setup:
```solidity
pragma solidity ^0.8.13;
import "lib/wormhole-solidity-sdk/src/WormholeRelayerSDK.sol";
import "lib/wormhole-solidity-sdk/src/interfaces/IERC20.sol";
contract CrossChainReceiver is TokenReceiver {
// The Wormhole relayer and registeredSenders are inherited from the Base.sol contract
constructor(
address _wormholeRelayer,
address _tokenBridge,
address _wormhole
) TokenBase(_wormholeRelayer, _tokenBridge, _wormhole) {}
```
Similar to the `CrossChainSender` contract, this sets up the basic structure of the contract, including the necessary imports and the constructor that initializes the contract with the Wormhole-related addresses.
3. Next, let's add a function inside the contract to handle receiving the payload and tokens:
```solidity
bytes memory payload,
TokenReceived[] memory receivedTokens,
bytes32 sourceAddress,
uint16 sourceChain,
bytes32 // deliveryHash
)
internal
override
onlyWormholeRelayer
isRegisteredSender(sourceChain, sourceAddress)
{
require(receivedTokens.length == 1, "Expected 1 token transfer");
// Decode the recipient address from the payload
address recipient = abi.decode(payload, (address));
// Transfer the received tokens to the intended recipient
IERC20(receivedTokens[0].tokenAddress).transfer(
recipient,
receivedTokens[0].amount
);
}
```
This `receivePayloadAndTokens` function processes the tokens and payload sent from another chain, decodes the recipient address, and transfers the tokens to them using the Wormhole protocol. This function also validates the emitter (`sourceAddress`) to ensure the message comes from a trusted sender.
This function ensures that:
- It only processes one token transfer at a time.
- The `sourceAddress` is checked against a list of registered senders using the `isRegisteredSender` modifier, which verifies if the emitter is allowed to send tokens to this contract.
- The recipient address is decoded from the payload, and the received tokens are transferred to them using the ERC-20 interface.
After we call `sendTokenWithPayloadToEvm` on the source chain, the message goes through the standard Wormhole message lifecycle. Once a [VAA (Verifiable Action Approval)](/docs/protocol/infrastructure/vaas/){target=\_blank} is available, the delivery provider will call `receivePayloadAndTokens` on the target chain and target address specified, with the appropriate inputs.
??? tip "Understanding the `TokenReceived` Struct"
Let’s delve into the fields provided to us in the `TokenReceived` struct:
```solidity
struct TokenReceived {
bytes32 tokenHomeAddress;
uint16 tokenHomeChain;
address tokenAddress;
uint256 amount;
uint256 amountNormalized;
}
```
- **`tokenHomeAddress`**: The original address of the token on its native chain. This is the same as the token field in the call to `sendTokenWithPayloadToEvm` unless the original token sent is a Wormhole-wrapped token. In that case, this will be the address of the original version of the token (on its native chain) in Wormhole address format (left-padded with 12 zeros).
- **`tokenHomeChain`**: The Wormhole chain ID corresponding to the home address above. This will typically be the source chain unless the original token sent is a Wormhole-wrapped asset, which will be the chain of the unwrapped version of the token.
- **`tokenAddress`**: The address of the IERC-20 token on the target chain that has been transferred to this contract. If `tokenHomeChain` equals the target chain, this will be the same as `tokenHomeAddress`; otherwise, it will be the Wormhole-wrapped version of the token sent.
- **`amount`**: The token amount sent to you with the same units as the original token. Since `TokenBridge` only sends with eight decimals of precision, if your token has 18 decimals, this will be the "amount" you sent, rounded down to the nearest multiple of 10^10.
- **`amountNormalized`**: The amount of token divided by (1 if decimals ≤ 8, else 10^(decimals - 8)).
You can find the complete code for the `CrossChainReceiver.sol` contract below:
??? code "CrossChainReceiver.sol"
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;
import "lib/wormhole-solidity-sdk/src/WormholeRelayerSDK.sol";
import "lib/wormhole-solidity-sdk/src/interfaces/IERC20.sol";
contract CrossChainReceiver is TokenReceiver {
// The Wormhole relayer and registeredSenders are inherited from the Base.sol contract
constructor(
address _wormholeRelayer,
address _tokenBridge,
address _wormhole
) TokenBase(_wormholeRelayer, _tokenBridge, _wormhole) {}
// Function to receive the cross-chain payload and tokens with emitter validation
function receivePayloadAndTokens(
bytes memory payload,
TokenReceived[] memory receivedTokens,
bytes32 sourceAddress,
uint16 sourceChain,
bytes32 // deliveryHash
)
internal
override
onlyWormholeRelayer
isRegisteredSender(sourceChain, sourceAddress)
{
require(receivedTokens.length == 1, "Expected 1 token transfer");
// Decode the recipient address from the payload
address recipient = abi.decode(payload, (address));
// Transfer the received tokens to the intended recipient
IERC20(receivedTokens[0].tokenAddress).transfer(
recipient,
receivedTokens[0].amount
);
}
}
```
## Deploy the Contracts
Now that you've written the `CrossChainSender` and `CrossChainReceiver` contracts, it's time to deploy them to your chosen networks.
1. **Set up deployment configuration**: Before deploying, you must configure the networks and the deployment environment. This information is stored in a configuration file.
1. Create a directory named deploy-config in the root of your project:
```bash
mkdir deploy-config
```
2. Create a `config.json` file in the `deploy-config` directory:
```bash
touch deploy-config/config.json
```
3. Open the `config.json` file and add the following configuration:
```json
{
"chains": [
{
"description": "Avalanche testnet fuji",
"chainId": 6,
"rpc": "https://api.avax-test.network/ext/bc/C/rpc",
"tokenBridge": "0x61E44E506Ca5659E6c0bba9b678586fA2d729756",
"wormholeRelayer": "0xA3cF45939bD6260bcFe3D66bc73d60f19e49a8BB",
"wormhole": "0x7bbcE28e64B3F8b84d876Ab298393c38ad7aac4C"
},
{
"description": "Celo Testnet",
"chainId": 14,
"rpc": "https://alfajores-forno.celo-testnet.org",
"tokenBridge": "0x05ca6037eC51F8b712eD2E6Fa72219FEaE74E153",
"wormholeRelayer": "0x306B68267Deb7c5DfCDa3619E22E9Ca39C374f84",
"wormhole": "0x88505117CA88e7dd2eC6EA1E13f0948db2D50D56"
}
]
}
```
This file specifies the details for each chain where you plan to deploy your contracts, including the RPC URL, the `TokenBridge` address, the Wormhole relayer, and the Wormhole Core contract.
For a complete list of Wormhole contract addresses on various blockchains, refer to the [Wormhole Contract Addresses](/docs/products/reference/contract-addresses/){target=\_blank}.
!!! note
You can add your desired chains to this file by specifying the required fields for each chain. In this example, we use the Avalanche Fuji and Celo Alfajores Testnets.
4. Create a `contracts.json` file in the `deploy-config` directory:
```bash
echo '{}' > deploy-config/contracts.json
```
This file can be left blank initially. It will be automatically updated with the deployed contract addresses after a successful deployment.
2. **Set up your Node.js environment**: You'll need to set up your Node.js environment to run the deployment script.
1. Initialize a Node.js project:
```bash
npm init -y
```
2. Create a `.gitignore` file to ensure your private key isn't accidentally exposed or committed to version control:
```bash
echo ".env" >> .gitignore
```
3. Install the necessary dependencies:
```bash
npm install ethers dotenv readline-sync @types/readline-sync
```
These dependencies are required for the deployment script to work properly.
3. **Compile your smart contracts**: Compile your smart contracts using Foundry. This ensures that your contracts are up-to-date and ready for deployment.
- Run the following command to compile your contracts:
```bash
forge build
```
This will generate the necessary ABI and bytecode files in a directory named `/out`.
The expected output should be similar to this:
forge build > [⠒] Compiling... > [⠰] Compiling 30 files with 0.8.23 [⠔] Solc 0.8.23 finished in 2.29sCompiler run successful!
4. **Write the deployment script**: You’ll need a script to automate the deployment of your contracts. Let’s create the deployment script.
1. Create a new file named `deploy.ts` in the `/script` directory:
```bash
touch script/deploy.ts
```
2. Open the file and load imports and configuration:
```typescript
import * as fs from 'fs';
import * as path from 'path';
import * as dotenv from 'dotenv';
import readlineSync from 'readline-sync';
dotenv.config();
```
Import the required libraries and modules to interact with Ethereum, handle file paths, load environment variables, and enable user interaction via the terminal.
3. Define interfaces to use for chain configuration and contract deployment:
```typescript
description: string;
chainId: number;
rpc: string;
tokenBridge: string;
wormholeRelayer: string;
wormhole: string;
}
interface DeployedContracts {
[chainId: number]: {
networkName: string;
CrossChainSender?: string;
CrossChainReceiver?: string;
deployedAt: string;
};
}
```
These interfaces define the structure of the chain configuration and the contract deployment details.
4. Load and select the chains for deployment:
```typescript
const configPath = path.resolve(__dirname, '../deploy-config/config.json');
return JSON.parse(fs.readFileSync(configPath, 'utf8')).chains;
}
function selectChain(
chains: ChainConfig[],
role: 'source' | 'target'
): ChainConfig {
console.log(`\nSelect the ${role.toUpperCase()} chain:`);
chains.forEach((chain, index) => {
console.log(`${index + 1}: ${chain.description}`);
});
const chainIndex =
readlineSync.questionInt(
`\nEnter the number for the ${role.toUpperCase()} chain: `
) - 1;
return chains[chainIndex];
}
```
The `loadConfig` function reads the chain configuration from the `config.json` file, and the `selectChain` function allows the user to choose the source and target chains for deployment interactively. The user is prompted in the terminal to select which chains to use, making the process interactive and user-friendly.
5. Define the main function for deployment and load the chain configuration:
```typescript
const chains = loadConfig();
const sourceChain = selectChain(chains, 'source');
const targetChain = selectChain(chains, 'target');
```
- The `main` function is the entry point for the deployment script.
- We then call the `loadConfig` function we previously defined to load the chain configuration from the `config.json` file.
6. Set up provider and wallet:
```typescript
const targetProvider = new ethers.JsonRpcProvider(targetChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY!, sourceProvider);
```
The scripts establish a connection to the blockchain using a provider and create a wallet instance using a private key. This wallet is responsible for signing the deployment transaction on the source chain.
7. Read the compiled contracts:
```typescript
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainSender.sol/CrossChainSender.json'
),
'utf8'
)
);
```
- This code reads the `CrossChainSender.json` file, the compiled output of the `CrossChainSender.sol` contract.
- The file is in the `../out/` directory, which contains the ABI (Application Binary Interface) and bytecode generated during contract compilation.
- It uses the `fs.readFileSync` function to read the file and `JSON.parse` to convert the file contents (in JSON format) into a JavaScript object.
8. Extract the contract ABI and bytecode:
```typescript
const bytecode = senderJson.bytecode;
```
- **ABI (Application Binary Interface)**: Defines the structure of the contract’s functions, events, and data types, allowing the front end to interact with the contract on the blockchain.
- **Bytecode**: This is the compiled machine code that will be deployed to the blockchain to create the contract.
9. Create the Contract Factory:
```typescript
abi,
bytecode,
wallet
);
```
- **`ethers.ContractFactory`**: Creates a new contract factory using the ABI, bytecode, and a wallet (representing the signer). The contract factory is responsible for deploying instances of the contract to the blockchain.
- This is a crucial step for deploying the contract since the factory will create and deploy the `CrossChainSender` contract.
10. Deploy the `CrossChainSender` and `CrossChainReceiver` contracts:
=== "`CrossChainSender`"
```typescript
const senderContract = await CrossChainSenderFactory.deploy(
sourceChain.wormholeRelayer,
sourceChain.tokenBridge,
sourceChain.wormhole
);
await senderContract.waitForDeployment();
```
=== "`CrossChainReceiver`"
```typescript
process.env.PRIVATE_KEY!,
targetProvider
);
const receiverJson = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainReceiver.sol/CrossChainReceiver.json'
),
'utf8'
)
);
const CrossChainReceiverFactory = new ethers.ContractFactory(
receiverJson.abi,
receiverJson.bytecode,
targetWallet
);
const receiverContract = await CrossChainReceiverFactory.deploy(
targetChain.wormholeRelayer,
targetChain.tokenBridge,
targetChain.wormhole
);
await receiverContract.waitForDeployment();
```
Both functions deploy the respective contracts to the selected chains.
For the `CrossChainReceiver` contract:
- It defines the wallet related to the target chain.
- The logic reads the compiled ABI and bytecode from the JSON file generated during compilation.
- It creates a new contract factory using the ABI, bytecode, and wallet.
- It deploys the contract to the selected chain passing in the Wormhole Relayer, `TokenBridge`, and Wormhole addresses.
11. Save the deployed contract addresses:
=== "`senderAddress`"
```typescript
console.log(
`CrossChainSender on ${sourceChain.description}: ${senderAddress}`
);
```
=== "`receiverAddress`"
```typescript
console.log(
`CrossChainReceiver on ${targetChain.description}: ${receiverAddress}`
);
```
You may display the deployed contract addresses in the terminal or save them to a JSON file for future reference.
12. Register the `CrossChainSender` address on the target chain:
```typescript
receiverAddress,
receiverJson.abi,
targetWallet
);
const tx = await CrossChainReceiverContract.setRegisteredSender(
sourceChain.chainId,
ethers.zeroPadValue(senderAddress as BytesLike, 32)
);
await tx.wait();
```
After you deploy the `CrossChainReceiver` contract on the target network, the sender contract address from the source chain needs to be registered. This ensures that only messages from the registered `CrossChainSender` contract are processed.
This additional step is essential to enforce emitter validation, preventing unauthorized senders from delivering messages to the `CrossChainReceiver` contract.
13. Save the deployment details:
???- example "Save Deployment Details Example"
```typescript
__dirname,
'../deploy-config/contracts.json'
);
let deployedContracts: DeployedContracts = {};
if (fs.existsSync(deployedContractsPath)) {
deployedContracts = JSON.parse(
fs.readFileSync(deployedContractsPath, 'utf8')
);
}
// Update the contracts.json file:
// If a contract already exists on a chain, update its address; otherwise, add a new entry.
if (!deployedContracts[sourceChain.chainId]) {
deployedContracts[sourceChain.chainId] = {
networkName: sourceChain.description,
deployedAt: new Date().toISOString(),
};
}
deployedContracts[sourceChain.chainId].CrossChainSender =
senderAddress.toString();
deployedContracts[sourceChain.chainId].deployedAt =
new Date().toISOString();
if (!deployedContracts[targetChain.chainId]) {
deployedContracts[targetChain.chainId] = {
networkName: targetChain.description,
deployedAt: new Date().toISOString(),
};
}
deployedContracts[targetChain.chainId].CrossChainReceiver =
receiverAddress.toString();
deployedContracts[targetChain.chainId].deployedAt =
new Date().toISOString();
// Save the updated contracts.json file
fs.writeFileSync(
deployedContractsPath,
JSON.stringify(deployedContracts, null, 2)
);
```
Add your desired logic to save the deployed contract addresses in a JSON file (or another format). This will be important later when transferring tokens, as you'll need these addresses to interact with the deployed contracts.
14. Handle errors and finalize the script:
```typescript
if (error.code === 'INSUFFICIENT_FUNDS') {
console.error(
'Error: Insufficient funds for deployment. Please make sure your wallet has enough funds to cover the gas fees.'
);
} else {
console.error('An unexpected error occurred:', error.message);
}
process.exit(1);
}
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
The try-catch block wraps the deployment logic to catch any errors that may occur.
- If the error is due to insufficient funds, it logs a clear message about needing more gas fees.
- For any other errors, it logs the specific error message to help with debugging.
The `process.exit(1)` ensures that the script exits with a failure status code if any error occurs.
You can find the full code for the `deploy.ts` file below:
??? code "deploy.ts"
```solidity
import { BytesLike, ethers } from 'ethers';
import * as fs from 'fs';
import * as path from 'path';
import * as dotenv from 'dotenv';
import readlineSync from 'readline-sync';
dotenv.config();
interface ChainConfig {
description: string;
chainId: number;
rpc: string;
tokenBridge: string;
wormholeRelayer: string;
wormhole: string;
}
interface DeployedContracts {
[chainId: number]: {
networkName: string;
CrossChainSender?: string;
CrossChainReceiver?: string;
deployedAt: string;
};
}
function loadConfig(): ChainConfig[] {
const configPath = path.resolve(__dirname, '../deploy-config/config.json');
return JSON.parse(fs.readFileSync(configPath, 'utf8')).chains;
}
function selectChain(
chains: ChainConfig[],
role: 'source' | 'target'
): ChainConfig {
console.log(`\nSelect the ${role.toUpperCase()} chain:`);
chains.forEach((chain, index) => {
console.log(`${index + 1}: ${chain.description}`);
});
const chainIndex =
readlineSync.questionInt(
`\nEnter the number for the ${role.toUpperCase()} chain: `
) - 1;
return chains[chainIndex];
}
async function main() {
const chains = loadConfig();
const sourceChain = selectChain(chains, 'source');
const targetChain = selectChain(chains, 'target');
const sourceProvider = new ethers.JsonRpcProvider(sourceChain.rpc);
const targetProvider = new ethers.JsonRpcProvider(targetChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY!, sourceProvider);
const senderJson = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainSender.sol/CrossChainSender.json'
),
'utf8'
)
);
const abi = senderJson.abi;
const bytecode = senderJson.bytecode;
const CrossChainSenderFactory = new ethers.ContractFactory(
abi,
bytecode,
wallet
);
try {
const senderContract = await CrossChainSenderFactory.deploy(
sourceChain.wormholeRelayer,
sourceChain.tokenBridge,
sourceChain.wormhole
);
await senderContract.waitForDeployment();
// Safely access the deployed contract's address
const senderAddress = (senderContract as ethers.Contract).target;
console.log(
`CrossChainSender on ${sourceChain.description}: ${senderAddress}`
);
const targetWallet = new ethers.Wallet(
process.env.PRIVATE_KEY!,
targetProvider
);
const receiverJson = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainReceiver.sol/CrossChainReceiver.json'
),
'utf8'
)
);
const CrossChainReceiverFactory = new ethers.ContractFactory(
receiverJson.abi,
receiverJson.bytecode,
targetWallet
);
const receiverContract = await CrossChainReceiverFactory.deploy(
targetChain.wormholeRelayer,
targetChain.tokenBridge,
targetChain.wormhole
);
await receiverContract.waitForDeployment();
// Safely access the deployed contract's address
const receiverAddress = (receiverContract as ethers.Contract).target;
console.log(
`CrossChainReceiver on ${targetChain.description}: ${receiverAddress}`
);
// Register the sender contract in the receiver contract
console.log(
`Registering CrossChainSender (${senderAddress}) as a valid sender in CrossChainReceiver (${receiverAddress})...`
);
const CrossChainReceiverContract = new ethers.Contract(
receiverAddress,
receiverJson.abi,
targetWallet
);
const tx = await CrossChainReceiverContract.setRegisteredSender(
sourceChain.chainId,
ethers.zeroPadValue(senderAddress as BytesLike, 32)
);
await tx.wait();
console.log(
`CrossChainSender registered as a valid sender on ${targetChain.description}`
);
// Load existing deployed contract addresses from contracts.json
const deployedContractsPath = path.resolve(
__dirname,
'../deploy-config/contracts.json'
);
let deployedContracts: DeployedContracts = {};
if (fs.existsSync(deployedContractsPath)) {
deployedContracts = JSON.parse(
fs.readFileSync(deployedContractsPath, 'utf8')
);
}
// Update the contracts.json file:
// If a contract already exists on a chain, update its address; otherwise, add a new entry.
if (!deployedContracts[sourceChain.chainId]) {
deployedContracts[sourceChain.chainId] = {
networkName: sourceChain.description,
deployedAt: new Date().toISOString(),
};
}
deployedContracts[sourceChain.chainId].CrossChainSender =
senderAddress.toString();
deployedContracts[sourceChain.chainId].deployedAt =
new Date().toISOString();
if (!deployedContracts[targetChain.chainId]) {
deployedContracts[targetChain.chainId] = {
networkName: targetChain.description,
deployedAt: new Date().toISOString(),
};
}
deployedContracts[targetChain.chainId].CrossChainReceiver =
receiverAddress.toString();
deployedContracts[targetChain.chainId].deployedAt =
new Date().toISOString();
// Save the updated contracts.json file
fs.writeFileSync(
deployedContractsPath,
JSON.stringify(deployedContracts, null, 2)
);
} catch (error: any) {
if (error.code === 'INSUFFICIENT_FUNDS') {
console.error(
'Error: Insufficient funds for deployment. Please make sure your wallet has enough funds to cover the gas fees.'
);
} else {
console.error('An unexpected error occurred:', error.message);
}
process.exit(1);
}
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
5. **Add your private key**: You'll need to provide your private key. It allows your deployment script to sign the transactions that deploy the smart contracts to the blockchain. Without it, the script won't be able to interact with the blockchain on your behalf.
Create a `.env` file in the root of the project and add your private key:
```bash
touch .env
```
Inside `.env`, add your private key in the following format:
```env
PRIVATE_KEY=INSERT_PRIVATE_KEY
```
6. **Run the deployment script**:
1. Open a terminal and run the following command:
```bash
npx ts-node script/deploy.ts
```
This will execute the deployment script, deploying both contracts to the selected chains.
2. Check the deployment output:
- You will see the deployed contract addresses printed in the terminal if successful. The `contracts.json` file will be updated with these addresses.
- If you encounter an error, the script will provide feedback, such as insufficient funds for gas.
If you followed the logic provided in the full code above, your terminal output should look something like this:
npx ts-node deploy.ts > cross-chain-token-transfer@1.0.0 deploy > npx ts-node script/deploy.ts Select the SOURCE chain: 1: Avalanche testnet fuji 2: Celo Testnet Enter the number for the SOURCE chain: 1 Select the TARGET chain: 1: Avalanche testnet fuji 2: Celo Testnet Enter the number for the TARGET chain: 2 CrossChainSender Avalanche testnet fuji: 0x1Cac52a183D02F9002fdb37b13eC2fAB950d44E3 CrossChainReceiver Celo Testnet: 0xD720BFF42a0960cfF1118454A907a44dB358f2b1 Registering CrossChainSender (0x1Cac52a183D02F9002fdb37b13eC2fAB950d44E3) as a valid sender in CrossChainReceiver (0xD720BFF42a0960cfF1118454A907a44dB358f2b1)... CrossChainSender registered as a valid sender on Celo Testnet
## Transfer Tokens Across Chains
### Quick Recap
Up to this point, you've set up a new Solidity project using Foundry, developed two key contracts (`CrossChainSender` and `CrossChainReceiver`), and created a deployment script to deploy these contracts to different blockchain networks. The deployment script also saves the new contract addresses for easy reference. With everything in place, it's time to transfer tokens using the deployed contracts.
In this step, you'll write a script to transfer tokens across chains using the `CrossChainSender` and `CrossChainReceiver` contracts you deployed earlier. This script will interact with the contracts and facilitate the cross-chain token transfer.
### Transfer Script
1. Set up the transfer script:
1. Create a new file named `transfer.ts` in the `/script` directory:
```bash
touch script/transfer.ts
```
2. Open the file. Start with the necessary imports, interfaces and configurations:
```typescript
import * as fs from 'fs';
import * as path from 'path';
import * as dotenv from 'dotenv';
import readlineSync from 'readline-sync';
dotenv.config();
interface ChainConfig {
description: string;
chainId: number;
rpc: string;
tokenBridge: string;
wormholeRelayer: string;
wormhole: string;
}
interface DeployedContracts {
[chainId: number]: {
networkName: string;
CrossChainSender?: string;
CrossChainReceiver?: string;
deployedAt: string;
};
}
```
These imports include the essential libraries for interacting with Ethereum, handling file paths, loading environment variables, and managing user input.
3. Load configuration and contracts:
```typescript
const configPath = path.resolve(__dirname, '../deploy-config/config.json');
return JSON.parse(fs.readFileSync(configPath, 'utf8')).chains;
}
function loadDeployedContracts(): DeployedContracts {
const contractsPath = path.resolve(
__dirname,
'../deploy-config/contracts.json'
);
if (
!fs.existsSync(contractsPath) ||
fs.readFileSync(contractsPath, 'utf8').trim() === ''
) {
console.error(
'No contracts found. Please deploy contracts first before transferring tokens.'
);
process.exit(1);
}
return JSON.parse(fs.readFileSync(contractsPath, 'utf8'));
}
```
These functions load the network and contract details that were saved during deployment.
4. Allow users to select source and target chains:
Refer to the deployed contracts and create logic as desired. In our example, we made this process interactive, allowing users to select the source and target chains from all the historically deployed contracts. This interactive approach helps ensure the correct chains are selected for the token transfer.
```typescript
chainId: number;
networkName: string;
} {
const sourceOptions = Object.entries(deployedContracts).filter(
([, contracts]) => contracts.CrossChainSender
);
if (sourceOptions.length === 0) {
console.error('No source chains available with CrossChainSender deployed.');
process.exit(1);
}
console.log('\nSelect the source chain:');
sourceOptions.forEach(([chainId, contracts], index) => {
console.log(`${index + 1}: ${contracts.networkName}`);
});
const selectedIndex =
readlineSync.questionInt(`\nEnter the number for the source chain: `) - 1;
return {
chainId: Number(sourceOptions[selectedIndex][0]),
networkName: sourceOptions[selectedIndex][1].networkName,
};
}
function selectTargetChain(deployedContracts: DeployedContracts): {
chainId: number;
networkName: string;
} {
const targetOptions = Object.entries(deployedContracts).filter(
([, contracts]) => contracts.CrossChainReceiver
);
if (targetOptions.length === 0) {
console.error(
'No target chains available with CrossChainReceiver deployed.'
);
process.exit(1);
}
console.log('\nSelect the target chain:');
targetOptions.forEach(([chainId, contracts], index) => {
console.log(`${index + 1}: ${contracts.networkName}`);
});
const selectedIndex =
readlineSync.questionInt(`\nEnter the number for the target chain: `) - 1;
return {
chainId: Number(targetOptions[selectedIndex][0]),
networkName: targetOptions[selectedIndex][1].networkName,
};
}
```
2. Implement the token transfer logic:
1. **Create the `main` function**: Add the token transfer logic, including the chain and contract details, wallet and provider for the source chain, and the `CrossChainSender` contract for interaction.
```typescript
const chains = loadConfig();
const deployedContracts = loadDeployedContracts();
// Select the source chain (only show chains with CrossChainSender deployed)
const { chainId: sourceChainId, networkName: sourceNetworkName } =
selectSourceChain(deployedContracts);
const sourceChain = chains.find((chain) => chain.chainId === sourceChainId)!;
// Select the target chain (only show chains with CrossChainReceiver deployed)
const { chainId: targetChainId, networkName: targetNetworkName } =
selectTargetChain(deployedContracts);
const targetChain = chains.find((chain) => chain.chainId === targetChainId)!;
// Set up providers and wallets
const sourceProvider = new ethers.JsonRpcProvider(sourceChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY!, sourceProvider);
// Load the ABI from the JSON file (use the compiled ABI from Forge or Hardhat)
const CrossChainSenderArtifact = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainSender.sol/CrossChainSender.json'
),
'utf8'
)
);
const abi = CrossChainSenderArtifact.abi;
// Create the contract instance using the full ABI
const CrossChainSender = new ethers.Contract(
deployedContracts[sourceChainId].CrossChainSender!,
abi,
wallet
);
```
2. **Ask the user for token transfer details**: You'll now ask the user for the token contract address, the recipient address on the target chain, and the amount of tokens to transfer.
```typescript
'Enter the token contract address: '
);
const recipientAddress = readlineSync.question(
'Enter the recipient address on the target chain: '
);
// Get the token contract
const tokenContractDecimals = new ethers.Contract(
tokenAddress,
[
'function decimals() view returns (uint8)',
'function approve(address spender, uint256 amount) public returns (bool)',
],
wallet
);
// Fetch the token decimals
const decimals = await tokenContractDecimals.decimals();
// Get the amount from the user, then parse it according to the token's decimals
const amount = ethers.parseUnits(
readlineSync.question('Enter the amount of tokens to transfer: '),
decimals
);
```
This section of the script prompts the user for the token contract address and the recipient's address, fetches the token's decimal value, and parses the amount accordingly.
3. **Initiate the transfer**: Finally, initiate the cross-chain transfer and log the details.
```typescript
// Approve the CrossChainSender contract to transfer tokens on behalf of the user
const tokenContract = new ethers.Contract(
tokenAddress,
['function approve(address spender, uint256 amount) public returns (bool)'],
wallet
);
const approveTx = await tokenContract.approve(
deployedContracts[sourceChainId].CrossChainSender!,
amount
);
await approveTx.wait();
console.log(`Approved tokens for cross-chain transfer.`);
// Initiate the cross-chain transfer
const transferTx = await CrossChainSender.sendCrossChainDeposit(
targetChainId,
deployedContracts[targetChainId].CrossChainReceiver!,
recipientAddress,
amount,
tokenAddress,
{ value: cost } // Attach the necessary fee for cross-chain transfer
);
await transferTx.wait();
console.log(
`Transfer initiated from ${sourceNetworkName} to ${targetNetworkName}. Transaction Hash: ${transferTx.hash}`
);
}
```
This part of the script first approves the token transfer, then initiates the cross-chain transfer using the `CrossChainSender` contract, and finally logs the transaction hash for the user to track.
4. **Finalize the script**: Call the `main` function and handle any errors that may occur during the token transfer process.
```typescript
console.error(error);
process.exit(1);
});
```
You can find the full code for the `transfer.ts` file below:
??? code "transfer.ts"
```solidity
import { ethers } from 'ethers';
import * as fs from 'fs';
import * as path from 'path';
import * as dotenv from 'dotenv';
import readlineSync from 'readline-sync';
dotenv.config();
interface ChainConfig {
description: string;
chainId: number;
rpc: string;
tokenBridge: string;
wormholeRelayer: string;
wormhole: string;
}
interface DeployedContracts {
[chainId: number]: {
networkName: string;
CrossChainSender?: string;
CrossChainReceiver?: string;
deployedAt: string;
};
}
function loadConfig(): ChainConfig[] {
const configPath = path.resolve(__dirname, '../deploy-config/config.json');
return JSON.parse(fs.readFileSync(configPath, 'utf8')).chains;
}
function loadDeployedContracts(): DeployedContracts {
const contractsPath = path.resolve(
__dirname,
'../deploy-config/contracts.json'
);
if (
!fs.existsSync(contractsPath) ||
fs.readFileSync(contractsPath, 'utf8').trim() === ''
) {
console.error(
'No contracts found. Please deploy contracts first before transferring tokens.'
);
process.exit(1);
}
return JSON.parse(fs.readFileSync(contractsPath, 'utf8'));
}
function selectSourceChain(deployedContracts: DeployedContracts): {
chainId: number;
networkName: string;
} {
const sourceOptions = Object.entries(deployedContracts).filter(
([, contracts]) => contracts.CrossChainSender
);
if (sourceOptions.length === 0) {
console.error('No source chains available with CrossChainSender deployed.');
process.exit(1);
}
console.log('\nSelect the source chain:');
sourceOptions.forEach(([chainId, contracts], index) => {
console.log(`${index + 1}: ${contracts.networkName}`);
});
const selectedIndex =
readlineSync.questionInt(`\nEnter the number for the source chain: `) - 1;
return {
chainId: Number(sourceOptions[selectedIndex][0]),
networkName: sourceOptions[selectedIndex][1].networkName,
};
}
function selectTargetChain(deployedContracts: DeployedContracts): {
chainId: number;
networkName: string;
} {
const targetOptions = Object.entries(deployedContracts).filter(
([, contracts]) => contracts.CrossChainReceiver
);
if (targetOptions.length === 0) {
console.error(
'No target chains available with CrossChainReceiver deployed.'
);
process.exit(1);
}
console.log('\nSelect the target chain:');
targetOptions.forEach(([chainId, contracts], index) => {
console.log(`${index + 1}: ${contracts.networkName}`);
});
const selectedIndex =
readlineSync.questionInt(`\nEnter the number for the target chain: `) - 1;
return {
chainId: Number(targetOptions[selectedIndex][0]),
networkName: targetOptions[selectedIndex][1].networkName,
};
}
async function main() {
const chains = loadConfig();
const deployedContracts = loadDeployedContracts();
// Select the source chain (only show chains with CrossChainSender deployed)
const { chainId: sourceChainId, networkName: sourceNetworkName } =
selectSourceChain(deployedContracts);
const sourceChain = chains.find((chain) => chain.chainId === sourceChainId)!;
// Select the target chain (only show chains with CrossChainReceiver deployed)
const { chainId: targetChainId, networkName: targetNetworkName } =
selectTargetChain(deployedContracts);
const targetChain = chains.find((chain) => chain.chainId === targetChainId)!;
// Set up providers and wallets
const sourceProvider = new ethers.JsonRpcProvider(sourceChain.rpc);
const wallet = new ethers.Wallet(process.env.PRIVATE_KEY!, sourceProvider);
// Load the ABI from the JSON file (use the compiled ABI from Forge or Hardhat)
const CrossChainSenderArtifact = JSON.parse(
fs.readFileSync(
path.resolve(
__dirname,
'../out/CrossChainSender.sol/CrossChainSender.json'
),
'utf8'
)
);
const abi = CrossChainSenderArtifact.abi;
// Create the contract instance using the full ABI
const CrossChainSender = new ethers.Contract(
deployedContracts[sourceChainId].CrossChainSender!,
abi,
wallet
);
// Display the selected chains
console.log(
`\nInitiating transfer from ${sourceNetworkName} to ${targetNetworkName}.`
);
// Ask the user for token transfer details
const tokenAddress = readlineSync.question(
'Enter the token contract address: '
);
const recipientAddress = readlineSync.question(
'Enter the recipient address on the target chain: '
);
// Get the token contract
const tokenContractDecimals = new ethers.Contract(
tokenAddress,
[
'function decimals() view returns (uint8)',
'function approve(address spender, uint256 amount) public returns (bool)',
],
wallet
);
// Fetch the token decimals
const decimals = await tokenContractDecimals.decimals();
// Get the amount from the user, then parse it according to the token's decimals
const amount = ethers.parseUnits(
readlineSync.question('Enter the amount of tokens to transfer: '),
decimals
);
// Calculate the cross-chain transfer cost
const cost = await CrossChainSender.quoteCrossChainDeposit(targetChainId);
// Approve the CrossChainSender contract to transfer tokens on behalf of the user
const tokenContract = new ethers.Contract(
tokenAddress,
['function approve(address spender, uint256 amount) public returns (bool)'],
wallet
);
const approveTx = await tokenContract.approve(
deployedContracts[sourceChainId].CrossChainSender!,
amount
);
await approveTx.wait();
console.log(`Approved tokens for cross-chain transfer.`);
// Initiate the cross-chain transfer
const transferTx = await CrossChainSender.sendCrossChainDeposit(
targetChainId,
deployedContracts[targetChainId].CrossChainReceiver!,
recipientAddress,
amount,
tokenAddress,
{ value: cost } // Attach the necessary fee for cross-chain transfer
);
await transferTx.wait();
console.log(
`Transfer initiated from ${sourceNetworkName} to ${targetNetworkName}. Transaction Hash: ${transferTx.hash}`
);
}
main().catch((error) => {
console.error(error);
process.exit(1);
});
```
### Transfer Tokens
Now that your transfer script is ready, it’s time to execute it and perform a cross-chain token transfer.
1. **Run the transfer script**: Open your terminal and run the transfer script.
```bash
npx ts-node script/transfer.ts
```
This command will start the script, prompting you to select the source and target chains, input the token address, recipient address, and the amount of tokens to transfer.
2. **Follow the prompts**: The script will guide you through selecting the source and target chains and entering the necessary details for the token transfer. Once you provide all the required information, the script will initiate the token transfer.
3. **Verify the transaction**: After running the script, you should see a confirmation message with the transaction hash. You can use this transaction hash to check the transfer status on the respective blockchain explorers.
You can verify the transaction on the [Wormhole Explorer](https://wormholescan.io/){target=\_blank} using the link provided in the terminal output. This explorer also offers the option to add the transferred token to your MetaMask wallet automatically.
If you followed the logic provided in the `transfer.ts` file above, your terminal output should look something like this:
npx ts-node transfer.ts > cross-chain-token-transfer@1.0.0 transfer > npx ts-node script/transfer.ts Select the source chain: 1: Avalanche testnet fuji 2: Celo Testnet Enter the number for the SOURCE chain: 1 Select the target chain: 1: Avalanche testnet fuji 2: Celo Testnet Enter the number for the TARGET chain: 2 Initiating transfer from Avalanche testnet fuji to Celo Testnet Enter the token contract address: 0x5425890298aed601595a70ab815c96711a31bc65 Enter the recipient address on the target chain: INSERT_YOUR_WALLET_ADDRESS Enter the amount of tokens to transfer: 2 Approved tokens for cross-chain transfer. Transfer initiated from Avalanche testnet fuji to Celo Testnet. Transaction Hash: 0x4a923975d955c1f226a1c2f61a1a0fa1ab1a9e229dc29ceaeadf8ef40acd071f
!!! note
In this example, we demonstrated a token transfer from the Avalanche Fuji Testnet to the Celo Alfajores Testnet. We sent two units of USDC Testnet tokens using the token contract address `0x5425890298aed601595a70ab815c96711a31bc65`. You can replace these details with those relevant to your project or use the same for testing purposes.
## Resources
If you'd like to explore the complete project or need a reference while following this tutorial, you can find the complete codebase in the [Cross-Chain Token Transfers GitHub repository](https://github.com/wormhole-foundation/demo-cross-chain-token-transfer){target=\_blank}. The repository includes all the scripts, contracts, and configurations needed to deploy and transfer tokens across chains using the Wormhole protocol.
## Conclusion
Congratulations! You've successfully built and deployed a cross-chain token transfer system using Solidity and the Wormhole protocol. You've learned how to:
- Set up a new Solidity project using Foundry.
- Develop smart contracts to send and receive tokens across chains.
- Write deployment scripts to manage and deploy contracts on different networks.
Looking for more? Check out the [Wormhole Tutorial Demo repository](https://github.com/wormhole-foundation/demo-tutorials){target=\_blank} for additional examples.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/tutorials/replace-signatures.md
--- BEGIN CONTENT ---
---
title: Replace Outdated Signatures in VAAs
description: Learn how to fetch, validate, and replace outdated signatures in Wormhole VAAs using Wormholescan and the Wormhole SDK to ensure seamless processing.
categories: Basics, Typescript SDK
---
# Replace Outdated Signatures in VAAs
:simple-github: [Source code on GitHub](https://github.com/wormhole-foundation/demo-vaa-signature-replacement){target=\_blank}
Cross-chain transactions in Wormhole rely on [Verifiable Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank}, which contain signatures from a trusted set of validators called [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank}. These signatures prove that the network approved an action, such as a token transfer.
However, the set of Guardians changes over time. If a user generates a transaction and waits too long before redeeming it, the Guardian set may have already changed. This means the VAA will contain outdated signatures from Guardians, who are no longer part of the network, causing the transaction to fail.
Instead of discarding these VAAs, we can fetch updated signatures and replace the outdated ones to ensure smooth processing.
In this tutorial, you'll build a script from scratch to:
- Fetch a VAA from [Wormholescan](https://wormholescan.io/#/developers/api-doc){target=\_blank}.
- Validate its signatures against the latest Guardian set.
- Replace outdated signatures using the [Wormhole SDK](https://github.com/wormhole-foundation/wormhole-sdk-ts){target=\_blank}.
- Output a valid VAA ready for submission.
By the end, you'll have a script that ensures VAAs remain valid and processable, avoiding transaction failures.
## Prerequisites
Before you begin, ensure you have the following:
- [Node.js and npm](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm){target=\_blank} installed on your machine.
- [TypeScript](https://www.typescriptlang.org/download/){target=\_blank} installed globally.
## Project Setup
In this section, you will create the directory, initialize a Node.js project, install dependencies, and configure TypeScript.
1. **Create the project**: Set up the directory and navigate into it.
```bash
mkdir wormhole-scan-api-demo
cd wormhole-scan-api-demo
```
2. **Initialize a Node.js project**: Generate a `package.json` file.
```bash
npm init -y
```
3. **Set up TypeScript**: Create a `tsconfig.json` file.
```bash
touch tsconfig.json
```
Then, add the following configuration:
```json title="tsconfig.json"
{
"compilerOptions": {
"target": "es2016",
"module": "commonjs",
"esModuleInterop": true,
"forceConsistentCasingInFileNames": true,
"strict": true,
"skipLibCheck": true
}
}
```
4. **Install dependencies**: Add the required packages.
```bash
npm install @wormhole-foundation/sdk axios web3 tsx @types/node
```
- **`@wormhole-foundation/sdk`**: Handles VAAs and cross-chain interactions.
- **`axios`**: Makes HTTP requests to the Wormholescan API.
- **`web3`**: Interacts with Ethereum transactions and contracts.
- **`tsx`**: Executes TypeScript files without compilation.
- **`@types/node`**: Provides Node.js type definitions.
5. **Create the project structure**: Set up the required directories and files.
```bash
mkdir -p src/config && touch src/config/constants.ts src/config/layouts.ts
mkdir -p src/helpers && touch src/helpers/vaaHelper.ts
mkdir -p src/scripts && touch scripts/replaceSignatures.ts
```
- **`src/config/*`**: Stores public configuration variables and layouts for serializing and deserializing data structures.
- **`src/helpers/*`**: Contains utility functions.
- **`src/scripts/*`**: Contains scripts for fetching and replacing signatures.
6. **Set variables**: Define key constants in `src/config/constants.ts`.
```bash title="src/config/constants.ts"
export const RPC = 'https://ethereum-rpc.publicnode.com';
export const ETH_CORE =
'0x98f3c9e6E3fAce36bAAd05FE09d375Ef1464288B'.toLowerCase();
export const WORMHOLESCAN_API = 'https://api.wormholescan.io/v1';
export const LOG_MESSAGE_PUBLISHED_TOPIC =
'0x6eb224fb001ed210e379b335e35efe88672a8ce935d981a6896b27ffdf52a3b2';
export const TXS = [
'0x3ad91ec530187bb2ce3b394d587878cd1e9e037a97e51fbc34af89b2e0719367',
'0x3c989a6bb40dcd4719453fbe7bbac420f23962c900ae75793124fc9cc614368c',
];
```
- **`RPC`**: Endpoint for interacting with an Ethereum RPC node.
- **`ETH_CORE`**: [Wormhole's Core Contract address on Ethereum](/docs/products/reference/contract-addresses/#core-contracts){target=\_blank} responsible for verifying VAAs.
- **`WORMHOLESCAN_API`**: Base URL for querying the Wormholescan API to fetch VAA data and Guardian sets.
- **`LOG_MESSAGE_PUBLISHED_TOPIC`**: The event signature hash for `LogMessagePublished`, a Wormhole contract event that signals when a VAA has been emitted. This is used to identify relevant logs in transaction receipts.
- **`TXS`**: List of example transaction hashes that will be used for testing.
7. **Define data structure for working with VAAs**: Specify the ABI for the Wormhole Core Contract's `parseAndVerifyVM` function, which parses and verifies VAAs. Defining the data structure, also referred to as a [layout](/docs/tools/typescript-sdk/guides/sdk-layout/){target=\_blank}, for this function ensures accurate decoding and validation of VAAs.
```typescript title="src/config/layouts.ts"
export const PARSE_AND_VERIFY_VM_ABI = {
inputs: [{ internalType: 'bytes', name: 'encodedVM', type: 'bytes' }],
name: 'parseAndVerifyVM',
outputs: [
{
components: [
{ internalType: 'uint8', name: 'version', type: 'uint8' },
{ internalType: 'uint32', name: 'timestamp', type: 'uint32' },
{ internalType: 'uint32', name: 'nonce', type: 'uint32' },
{ internalType: 'uint16', name: 'emitterChainId', type: 'uint16' },
{ internalType: 'bytes32', name: 'emitterAddress', type: 'bytes32' },
{ internalType: 'uint64', name: 'sequence', type: 'uint64' },
{ internalType: 'uint8', name: 'consistencyLevel', type: 'uint8' },
{ internalType: 'bytes', name: 'payload', type: 'bytes' },
{ internalType: 'uint32', name: 'guardianSetIndex', type: 'uint32' },
{
components: [
{ internalType: 'bytes32', name: 'r', type: 'bytes32' },
{ internalType: 'bytes32', name: 's', type: 'bytes32' },
{ internalType: 'uint8', name: 'v', type: 'uint8' },
{ internalType: 'uint8', name: 'guardianIndex', type: 'uint8' },
],
internalType: 'struct Structs.Signature[]',
name: 'signatures',
type: 'tuple[]',
},
{ internalType: 'bytes32', name: 'hash', type: 'bytes32' },
],
internalType: 'struct Structs.VM',
name: 'vm',
type: 'tuple',
},
{ internalType: 'bool', name: 'valid', type: 'bool' },
{ internalType: 'string', name: 'reason', type: 'string' },
],
stateMutability: 'view',
type: 'function',
};
```
## Create VAA Handling Functions
In this section, we'll create a series of helper functions in the `src/helpers/vaaHelper.ts` file that will retrieve and verify VAAs and fetch and replace outdated Guardian signatures to generate a correctly signed VAA.
To get started, import the necessary dependencies:
```typescript title="src/helpers/vaaHelper.ts"
import { eth } from 'web3';
import {
deserialize,
serialize,
VAA,
Signature,
} from '@wormhole-foundation/sdk';
import {
RPC,
ETH_CORE,
LOG_MESSAGE_PUBLISHED_TOPIC,
WORMHOLESCAN_API,
} from '../config/constants';
import { PARSE_AND_VERIFY_VM_ABI } from '../config/layouts';
```
### Fetch a VAA ID from a Transaction
To retrieve a VAA, we first need to get its VAA ID from a transaction hash. This ID allows us to fetch the full VAA later.
The VAA ID is structured as follows:
```bash
chain/emitter/sequence
```
- **`chain`**: The [Wormhole chain ID](/docs/products/reference/chain-ids/){target=\_blank} (Ethereum is 2).
- **`emitter`**: The contract address that emitted the VAA.
- **`sequence`**: A unique identifier for the event.
We must assemble the ID correctly since this is the format the Wormholescan API expects when querying VAAs.
Follow the below steps to process the transaction logs and construct the VAA ID:
1. **Get the transaction receipt**: Iterate over the array of transaction hashes and fetch the receipt to access its logs.
2. **Find the Wormhole event**: Iterate over the transaction logs and check for events emitted by the Wormhole Core contract. Look specifically for `LogMessagePublished` events, which indicate a VAA was created.
3. **Extract the emitter and sequence number**: If a matching event is found, extract the emitter address from `log.topics[1]` and remove the `0x` prefix. Then, the sequence number from `log.data` is extracted, converting it from hex to an integer.
4. **Construct the VAA ID**: Format the extracted data in `chain/emitter/sequence` format.
```typescript title="src/helpers/vaaHelper.ts"
const vaaIds: string[] = [];
for (const tx of txHashes) {
try {
const result = (
await axios.post(RPC, {
jsonrpc: '2.0',
id: 1,
method: 'eth_getTransactionReceipt',
params: [tx],
})
).data.result;
if (!result)
throw new Error(`Unable to fetch transaction receipt for ${tx}`);
for (const log of result.logs) {
if (
log.address === ETH_CORE &&
log.topics?.[0] === LOG_MESSAGE_PUBLISHED_TOPIC
) {
const emitter = log.topics[1].substring(2);
const seq = BigInt(log.data.substring(0, 66)).toString();
vaaIds.push(`2/${emitter}/${seq}`);
}
}
} catch (error) {
console.error(`Error processing ${tx}:`, error);
}
}
return vaaIds;
}
```
???- code "Try it out: VAA ID retrieval"
If you want to try out the function before moving forward, create a test file inside the `test` directory:
1. Create the directory and file:
```bash
mkdir -p test
touch test/fetchVaaId.run.ts
```
2. Add the function call:
```typescript title="test/fetchVaaId.run.ts"
import { fetchVaaId } from '../src/helpers/vaaHelper';
import { TXS } from '../src/config/constants';
const testFetchVaaId = async () => {
for (const tx of TXS) {
const vaaIds = await fetchVaaId([tx]);
if (vaaIds.length > 0) {
console.log(`Transaction: ${tx}`);
vaaIds.forEach((vaaId) => console.log(`VAA ID: ${vaaId}`));
} else {
console.log(`No VAA ID found for transaction: ${tx}`);
}
}
};
testFetchVaaId();
```
3. Run the script:
```bash
npx tsx test/fetchVaaId.run.ts
```
If successful, the output will be:
If no VAA ID is found, the script will log an error message.
### Fetch the Full VAA
Now that you have the VAA ID, we can use it to fetch the full VAA payload from the Wormholescan API. This payload contains the VAA bytes, which will later be used for signature validation.
Open `src/helpers/vaaHelper.ts` and create the `fetchVaa()` function to iterate through VAA IDs and extract the `vaaBytes` payload.
```typescript title="src/helpers/vaaHelper.ts"
vaaIds: string[]
): Promise<{ id: string; vaaBytes: string }[]> {
const results: { id: string; vaaBytes: string }[] = [];
for (const id of vaaIds) {
try {
const response = await axios.get(`${WORMHOLESCAN_API}/signed_vaa/${id}`);
const vaaBytes = response.data.vaaBytes;
results.push({ id, vaaBytes });
} catch (error) {
console.error(`Error fetching VAA for ${id}:`, error);
}
}
return results;
}
```
???- code "Try it out: VAA retrieval"
If you want to try the function before moving forward, create a script inside the `test` directory
1. Create the script file:
```bash
touch test/fetchVaa.run.ts
```
2. Add the function call:
```typescript title="test/fetchVaa.run.ts"
import { fetchVaaId, fetchVaa } from '../src/helpers/vaaHelper';
import { TXS } from '../src/config/constants';
const testFetchVaa = async () => {
for (const tx of TXS) {
const vaaIds = await fetchVaaId([tx]);
if (vaaIds.length === 0) {
console.log(`No VAA ID found for transaction: ${tx}`);
continue;
}
for (const vaaId of vaaIds) {
const vaaBytes = await fetchVaa([vaaId]);
console.log(
`Transaction: ${tx}\nVAA ID: ${vaaId}\nVAA Bytes: ${
vaaBytes.length > 0 ? vaaBytes[0].vaaBytes : 'Not found'
}`
);
}
}
};
testFetchVaa();
```
3. Run the script:
```bash
npx tsx test/fetchVaa.run.ts
```
If successful, the output will be:
If no VAA is found, the script will log an error message.
### Validate VAA Signatures
Now, we need to verify its validity. A VAA is only considered valid if it contains signatures from currently active Guardians and is correctly verified by the Wormhole Core contract.
Open `src/helpers/vaaHelper.ts` and add the `checkVaaValidity()` function. This function verifies whether a VAA is valid by submitting it to an Ethereum RPC node and checking for outdated signatures.
Follow these steps to implement the function:
1. **Prepare the VAA for verification**: Construct the VAA payload in a format that can be sent to the Wormhole Core contract.
2. **Send an `eth_call` request**: Submit the VAA to an Ethereum RPC node, calling the `parseAndVerifyVM` function on the Wormhole Core contract.
3. **Decode the response**: Check whether the VAA is valid. If it contains outdated signatures, further action will be required to replace them.
```typescript title="src/helpers/vaaHelper.ts"
try {
const vaa = Buffer.from(vaaBytes, 'base64');
vaa[4] = 4; // Set guardian set index to 4
const result = (
await axios.post(RPC, {
jsonrpc: '2.0',
id: 1,
method: 'eth_call',
params: [
{
from: null,
to: ETH_CORE,
data: eth.abi.encodeFunctionCall(PARSE_AND_VERIFY_VM_ABI, [
`0x${vaa.toString('hex')}`,
]),
},
'latest',
],
})
).data.result;
const decoded = eth.abi.decodeParameters(
PARSE_AND_VERIFY_VM_ABI.outputs,
result
);
console.log(
`${decoded.valid ? '✅' : '❌'} VAA Valid: ${decoded.valid}${
decoded.valid ? '' : `, Reason: ${decoded.reason}`
}`
);
return { valid: decoded.valid, reason: decoded.reason };
} catch (error) {
console.error(`Error checking VAA validity:`, error);
return { valid: false, reason: 'RPC error' };
}
}
```
???- code "Try it out: VAA Validity"
If you want to try the function before moving forward, create a script inside the `test` directory
1. Create the script file:
```bash
touch test/checkVaaValidity.run.ts
```
2. Add the function call:
```typescript title="test/checkVaaValidity.run.ts"
import {
fetchVaaId,
fetchVaa,
checkVaaValidity,
} from '../src/helpers/vaaHelper';
import { TXS } from '../src/config/constants';
const testCheckVaaValidity = async () => {
for (const tx of TXS) {
const vaaIds = await fetchVaaId([tx]);
if (vaaIds.length === 0) {
console.log(`No VAA ID found for transaction: ${tx}`);
continue;
}
for (const vaaId of vaaIds) {
const vaaData = await fetchVaa([vaaId]);
if (vaaData.length === 0 || !vaaData[0].vaaBytes) {
console.log(`VAA not found for ID: ${vaaId}`);
continue;
}
const result = await checkVaaValidity(vaaData[0].vaaBytes);
console.log(
`Transaction: ${tx}\nVAA ID: ${vaaId}\nVAA Validity:`,
result
);
}
}
};
testCheckVaaValidity();
```
3. Run the script:
```bash
npx tsx test/checkVaaValidity.run.ts
```
If the VAA is valid, the output will be:
### Fetch Observations (VAA Signatures)
Before replacing outdated signatures, we need to fetch the original VAA signatures from Wormholescan. This allows us to compare them with the latest Guardian set and determine which ones need updating.
Inside `src/helpers/vaaHelper.ts`, create the `fetchObservations()` function to query the Wormholescan API for observations related to a given VAA. Format the response by converting Guardian addresses to lowercase for consistency, and return an empty array if an error occurs.
```typescript title="src/helpers/vaaHelper.ts"
try {
console.log(`Fetching observations`);
const response = await axios.get(
`https://api.wormholescan.io/api/v1/observations/${vaaId}`
);
return response.data.map((obs: any) => ({
guardianAddr: obs.guardianAddr.toLowerCase(),
signature: obs.signature,
}));
} catch (error) {
console.error(`Error fetching observations:`, error);
return [];
}
}
```
???- code "Try it out: Fetch Observations"
If you want to try the function before moving forward, create a script inside the `test` directory
1. Create the script file:
```bash
touch test/fetchObservations.run.ts
```
2. Add the function call:
```typescript title="test/fetchObservations.run.ts"
import { fetchVaaId, fetchObservations } from '../src/helpers/vaaHelper';
import { TXS } from '../src/config/constants';
const testFetchObservations = async () => {
for (const tx of TXS) {
const vaaIds = await fetchVaaId([tx]);
if (vaaIds.length === 0) {
console.log(`No VAA ID found for transaction: ${tx}`);
continue;
}
for (const vaaId of vaaIds) {
const observations = await fetchObservations(vaaId);
if (observations.length === 0) {
console.log(`No observations found for VAA ID: ${vaaId}`);
continue;
}
console.log(
`Transaction: ${tx}\nVAA ID: ${vaaId}\nObservations:`,
observations
);
}
}
};
testFetchObservations();
```
3. Run the script:
```bash
npx tsx test/fetchObservations.run.ts
```
If successful, the output will be:
If no observations are found, the script will log an error message.
### Fetch the Latest Guardian Set
Now that we have the original VAA signatures, we must fetch the latest Guardian set from Wormholescan. This will allow us to compare the stored signatures with the current Guardians and determine which signatures need replacing.
Create the `fetchGuardianSet()` function inside `src/helpers/vaaHelper.ts` to fetch the latest Guardian set.
```typescript title="src/helpers/vaaHelper.ts"
export async function fetchGuardianSet() {
try {
console.log('Fetching current guardian set');
const response = await axios.get(`${WORMHOLESCAN_API}/guardianset/current`);
const guardians = response.data.guardianSet.addresses.map((addr: string) =>
addr.toLowerCase()
);
const guardianSet = response.data.guardianSet.index;
return [guardians, guardianSet];
} catch (error) {
console.error('Error fetching guardian set:', error);
return [];
}
}
```
???- code "Try it out: Fetch Guardian Set"
If you want to try the function before moving forward, create a script inside the `test` directory
1. Create the script file:
```bash
touch test/fetchGuardianSet.run.ts
```
2. Add the function call:
```typescript title="test/fetchGuardianSet.run.ts"
import { fetchGuardianSet } from '../src/helpers/vaaHelper';
const testFetchGuardianSet = async () => {
const [guardians, guardianSetIndex] = await fetchGuardianSet();
console.log('Current Guardian Set Index:', guardianSetIndex);
console.log('Guardian Addresses:', guardians);
};
testFetchGuardianSet();
```
3. Run the script:
```bash
npx tsx test/fetchGuardianSet.run.ts
```
If successful, the output will be:
npx tsx test/fetchGuardianSet.run.tsFetching current guardian setCurrent Guardian Set Index: 4Guardian Addresses: [
'0x5893b5a76c3f739645648885bdccc06cd70a3cd3',
'0xff6cb952589bde862c25ef4392132fb9d4a42157',
'0x114de8460193bdf3a2fcf81f86a09765f4762fd1',
'0x107a0086b32d7a0977926a205131d8731d39cbeb',
...]
If an error occurs while fetching the Guardian set, a `500` status error will be logged.
### Replace Outdated Signatures
With the full VAA, Guardian signatures, and the latest Guardian set, we can now update outdated signatures while maintaining the required signature count.
1. **Create the `replaceSignatures()` function**: Open `src/helpers/vaaHelper.ts` and add the function header. To catch and handle errors properly, all logic will be wrapped inside a `try` block.
```typescript title="src/helpers/vaaHelper.ts"
vaa: string | Uint8Array,
observations: { guardianAddr: string; signature: string }[],
currentGuardians: string[],
guardianSetIndex: number
) {
console.log('Replacing Signatures...');
try {
// Add logic in the following steps here
console.error('Unexpected error in replaceSignatures:', error);
}
}
```
- **`vaa`**: Original VAA bytes.
- **`observations`**: Observed signatures from the network.
- **`currentGuardians`**: Latest Guardian set.
- **`guardianSetIndex`**: Current Guardian set index.
2. **Validate input data**: Ensure all required parameters are present before proceeding. If any required input is missing, the function throws an error to prevent execution with incomplete data. The Guardian set should never be empty; if it is, this likely indicates an error in fetching the Guardian set in a previous step.
```typescript
if (currentGuardians.length === 0)
throw new Error('Guardian set is empty.');
if (observations.length === 0) throw new Error('No observations provided.');
```
3. **Filter valid signatures**: Remove signatures from inactive Guardians, keeping only valid ones. If there aren't enough valid signatures to replace the outdated ones, execution is halted to prevent an incomplete or invalid VAA.
```typescript
currentGuardians.includes(sig.guardianAddr)
);
if (validSigs.length === 0)
throw new Error('No valid signatures found. Cannot proceed.');
```
4. **Convert valid signatures**: Ensure signatures are correctly formatted for verification. Convert hex-encoded signatures if necessary and extract their components.
```typescript
.map((sig) => {
try {
const sigBuffer = Buffer.from(sig.signature, 'base64');
// If it's 130 bytes, it's hex-encoded and needs conversion
const sigBuffer1 =
sigBuffer.length === 130
? Buffer.from(sigBuffer.toString(), 'hex')
: sigBuffer;
const r = BigInt('0x' + sigBuffer1.subarray(0, 32).toString('hex'));
const s = BigInt('0x' + sigBuffer1.subarray(32, 64).toString('hex'));
const vRaw = sigBuffer1[64];
const v = vRaw < 27 ? vRaw : vRaw - 27;
return {
guardianIndex: currentGuardians.indexOf(sig.guardianAddr),
signature: new Signature(r, s, v),
};
} catch (error) {
console.error(
`Failed to process signature for guardian: ${sig.guardianAddr}`,
error
);
return null;
}
})
.filter(
(sig): sig is { guardianIndex: number; signature: Signature } =>
sig !== null
); // Remove null values
```
5. **Deserialize the VAA**: Convert the raw VAA data into a structured format for further processing.
```typescript
try {
parsedVaa = deserialize('Uint8Array', vaa);
} catch (error) {
throw new Error(`Error deserializing VAA: ${error}`);
}
```
6. **Identify outdated signatures**: Compare the current VAA signatures with the newly formatted ones to detect which signatures belong to outdated Guardians. Remove these outdated signatures to ensure only valid ones remain.
```typescript
.filter(
(vaaSig) =>
!formattedSigs.some(
(sig) => sig.guardianIndex === vaaSig.guardianIndex
)
)
.map((sig) => sig.guardianIndex);
console.log('Outdated Guardian Indexes:', outdatedGuardianIndexes);
let updatedSignatures = parsedVaa.signatures.filter(
(sig) => !outdatedGuardianIndexes.includes(sig.guardianIndex)
);
```
7. **Replace outdated signatures**: Substitute outdated signatures with valid ones while maintaining the correct number of signatures. If there aren’t enough valid replacements, execution stops.
```typescript
(sig) =>
!updatedSignatures.some((s) => s.guardianIndex === sig.guardianIndex)
);
// Check if we have enough valid signatures to replace outdated ones**
if (outdatedGuardianIndexes.length > validReplacements.length) {
console.warn(
`Not enough valid replacement signatures! Need ${outdatedGuardianIndexes.length}, but only ${validReplacements.length} available.`
);
return;
}
updatedSignatures = [
...updatedSignatures,
...validReplacements.slice(0, outdatedGuardianIndexes.length),
];
updatedSignatures.sort((a, b) => a.guardianIndex - b.guardianIndex);
```
8. **Serialize the updated VAA**: Reconstruct the VAA with the updated signatures and convert it into a format suitable for submission.
```typescript
...parsedVaa,
guardianSet: guardianSetIndex,
signatures: updatedSignatures,
};
let patchedVaa: Uint8Array;
try {
patchedVaa = serialize(updatedVaa);
} catch (error) {
throw new Error(`Error serializing updated VAA: ${error}`);
}
```
9. **Send the updated VAA for verification and handle errors**: Submit the updated VAA to an Ethereum RPC node for validation, ensuring it can be proposed for Guardian approval. If an error occurs during submission or signature replacement, log the issue and prevent further execution.
```typescript
if (!(patchedVaa instanceof Uint8Array))
throw new Error('Patched VAA is not a Uint8Array!');
const vaaHex = `0x${Buffer.from(patchedVaa).toString('hex')}`;
console.log('Sending updated VAA to RPC...');
const result = await axios.post(RPC, {
jsonrpc: '2.0',
id: 1,
method: 'eth_call',
params: [
{
from: null,
to: ETH_CORE,
data: eth.abi.encodeFunctionCall(PARSE_AND_VERIFY_VM_ABI, [vaaHex]),
},
'latest',
],
});
const verificationResult = result.data.result;
console.log('Updated VAA (hex):', vaaHex);
return verificationResult;
} catch (error) {
throw new Error(`Error sending updated VAA to RPC: ${error}`);
}
```
???- code "Complete Function"
```typescript
vaa: string | Uint8Array,
observations: { guardianAddr: string; signature: string }[],
currentGuardians: string[],
guardianSetIndex: number
) {
console.log('Replacing Signatures...');
try {
if (!vaa) throw new Error('VAA is undefined or empty.');
if (currentGuardians.length === 0)
throw new Error('Guardian set is empty.');
if (observations.length === 0) throw new Error('No observations provided.');
const validSigs = observations.filter((sig) =>
currentGuardians.includes(sig.guardianAddr)
);
if (validSigs.length === 0)
throw new Error('No valid signatures found. Cannot proceed.');
const formattedSigs = validSigs
.map((sig) => {
try {
const sigBuffer = Buffer.from(sig.signature, 'base64');
// If it's 130 bytes, it's hex-encoded and needs conversion
const sigBuffer1 =
sigBuffer.length === 130
? Buffer.from(sigBuffer.toString(), 'hex')
: sigBuffer;
const r = BigInt('0x' + sigBuffer1.subarray(0, 32).toString('hex'));
const s = BigInt('0x' + sigBuffer1.subarray(32, 64).toString('hex'));
const vRaw = sigBuffer1[64];
const v = vRaw < 27 ? vRaw : vRaw - 27;
return {
guardianIndex: currentGuardians.indexOf(sig.guardianAddr),
signature: new Signature(r, s, v),
};
} catch (error) {
console.error(
`Failed to process signature for guardian: ${sig.guardianAddr}`,
error
);
return null;
}
})
.filter(
(sig): sig is { guardianIndex: number; signature: Signature } =>
sig !== null
); // Remove null values
let parsedVaa: VAA<'Uint8Array'>;
try {
parsedVaa = deserialize('Uint8Array', vaa);
} catch (error) {
throw new Error(`Error deserializing VAA: ${error}`);
}
const outdatedGuardianIndexes = parsedVaa.signatures
.filter(
(vaaSig) =>
!formattedSigs.some(
(sig) => sig.guardianIndex === vaaSig.guardianIndex
)
)
.map((sig) => sig.guardianIndex);
console.log('Outdated Guardian Indexes:', outdatedGuardianIndexes);
let updatedSignatures = parsedVaa.signatures.filter(
(sig) => !outdatedGuardianIndexes.includes(sig.guardianIndex)
);
const validReplacements = formattedSigs.filter(
(sig) =>
!updatedSignatures.some((s) => s.guardianIndex === sig.guardianIndex)
);
// Check if we have enough valid signatures to replace outdated ones**
if (outdatedGuardianIndexes.length > validReplacements.length) {
console.warn(
`Not enough valid replacement signatures! Need ${outdatedGuardianIndexes.length}, but only ${validReplacements.length} available.`
);
return;
}
updatedSignatures = [
...updatedSignatures,
...validReplacements.slice(0, outdatedGuardianIndexes.length),
];
updatedSignatures.sort((a, b) => a.guardianIndex - b.guardianIndex);
const updatedVaa: VAA<'Uint8Array'> = {
...parsedVaa,
guardianSet: guardianSetIndex,
signatures: updatedSignatures,
};
let patchedVaa: Uint8Array;
try {
patchedVaa = serialize(updatedVaa);
} catch (error) {
throw new Error(`Error serializing updated VAA: ${error}`);
}
try {
if (!(patchedVaa instanceof Uint8Array))
throw new Error('Patched VAA is not a Uint8Array!');
const vaaHex = `0x${Buffer.from(patchedVaa).toString('hex')}`;
console.log('Sending updated VAA to RPC...');
const result = await axios.post(RPC, {
jsonrpc: '2.0',
id: 1,
method: 'eth_call',
params: [
{
from: null,
to: ETH_CORE,
data: eth.abi.encodeFunctionCall(PARSE_AND_VERIFY_VM_ABI, [vaaHex]),
},
'latest',
],
});
const verificationResult = result.data.result;
console.log('Updated VAA (hex):', vaaHex);
return verificationResult;
} catch (error) {
throw new Error(`Error sending updated VAA to RPC: ${error}`);
}
} catch (error) {
console.error('Unexpected error in replaceSignatures:', error);
}
}
```
## Create Script to Replace Outdated VAA Signatures
Now that we have all the necessary helper functions, we will create a script to automate replacing outdated VAA signatures. This script will retrieve a transaction’s VAA sequentially, check its validity, fetch the latest Guardian set, and update its signatures. By the end, it will output a correctly signed VAA that can be proposed for Guardian approval.
1. **Open the file**: Inside `src/scripts/replaceSignatures.ts`, import the required helper functions needed to process the VAAs.
```typescript title="src/scripts/replaceSignatures.ts"
fetchVaaId,
fetchVaa,
checkVaaValidity,
fetchObservations,
fetchGuardianSet,
replaceSignatures,
} from '../helpers/vaaHelper';
import { TXS } from '../config/constants';
```
2. **Define the main execution function**: Add the following function inside `src/scripts/replaceSignatures.ts` to process each transaction in `TXS`, going step by step through the signature replacement process.
```typescript
try {
for (const tx of TXS) {
console.log(`\nProcessing TX: ${tx}\n`);
// 1. Fetch Transaction VAA IDs:
const vaaIds = await fetchVaaId([tx]);
if (!vaaIds.length) continue;
// 2. Fetch VAA Data:
const vaaData = await fetchVaa(vaaIds);
if (!vaaData.length) continue;
const vaaBytes = vaaData[0].vaaBytes;
if (!vaaBytes) continue;
// 3. Check VAA Validity:
const { valid } = await checkVaaValidity(vaaBytes);
if (valid) continue;
// 4. Fetch Observations (VAA signatures):
const observations = await fetchObservations(vaaIds[0]);
// 5. Fetch Current Guardian Set:
const [currentGuardians, guardianSetIndex] = await fetchGuardianSet();
// 6. Replace Signatures:
const response = await replaceSignatures(
Buffer.from(vaaBytes, 'base64'),
observations,
currentGuardians,
guardianSetIndex
);
if (!response) continue;
}
} catch (error) {
console.error('❌ Error in execution:', error);
process.exit(1);
}
}
```
3. **Make the script executable**: Ensure it runs when executed.
```typescript
```
To run the script, use the following command:
```bash
npx tsx src/scripts/replaceSignatures.ts
```
npx tsx src/scripts/replaceSignatures.tsProcessing TX: 0x3ad91ec530187bb2ce3b394d587878cd1e9e037a97e51fbc34af89b2e0719367❌ VAA Valid: false, Reason: VM signature invalidFetching observationsFetching current guardian setReplacing Signatures...Outdated Guardian Indexes: [ 0 ]Sending updated VAA to RPC...Updated VAA (hex): 0x01000000040d010019447b72d51e33923a3d6b28496ccd3722d5f1e33e2...
The script logs each step, skipping valid VAAs, replacing outdated signatures for invalid VAAs, and logging any errors. It then completes with a valid VAA ready for submission.
## Resources
You can explore the complete project and find all necessary scripts and configurations in Wormhole's [demo GitHub repository](https://github.com/wormhole-foundation/demo-vaa-signature-replacement){target=\_blank}.
The demo repository includes a bonus script to check the VAA redemption status on Ethereum and Solana, allowing you to verify whether a transaction has already been redeemed on the destination chain.
## Conclusion
You've successfully built a script to fetch, validate, and replace outdated signatures in VAAs using Wormholescan and the Wormhole SDK.
It's important to note that this tutorial does not update VAAs in the Wormhole network. Before redeeming the VAA, you must propose it for Guardian approval to finalize the process.
Looking for more? Check out the [Wormhole Tutorial Demo repository](https://github.com/wormhole-foundation/demo-tutorials){target=\_blank} for additional examples.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/architecture.md
--- BEGIN CONTENT ---
---
title: Architecture
description: Overview of Wormhole's architecture, detailing key on-chain and off-chain components like the Core Contract, Guardian Network, and relayers.
categories: Basics
---
# Architecture
Wormhole has several noteworthy components. Before discussing each component in depth, this page will provide an overview of how the major pieces fit together.

The preceding diagram outlines the end-to-end flow of multichain communication through Wormhole's architecture, which is described as follows:
1. **Source chain**: A source contract emits a message by interacting with the [Wormhole Core Contract](/docs/protocol/infrastructure/core-contracts/){target=\_blank} on the source chain, which publishes the message in the blockchain's transaction logs.
2. **Guardian Network**: [Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} validate these messages and sign them to produce [Verifiable Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank}.
3. **Relayers**: Off-chain relayers or applications fetch the VAA and relay it to the target chain.
4. **Target chain**: On the target chain, the message is consumed by the appropriate contract. This contract interacts with the Wormhole Core Contract to verify the VAA and execute the intended multichain operation.
The flow from the relayer to the target chain involves an entry point contract, which could vary based on the use case:
- In some applications, the target contract acts as the entry point and performs verification via the Core Contract.
- In products like Wrapped Token Transfers (WTT), the WTT contract itself interacts with the Core Contract.
## On-Chain Components
- **Emitter**: A contract that calls the publish message method on the Core Contract. To identify the message, the Core Contract will write an event to the transaction logs with details about the emitter and sequence number. This may be your cross-chain dApp or an existing ecosystem protocol.
- **[Wormhole Core Contract](/docs/protocol/infrastructure/core-contracts/){target=\_blank}**: Primary contract, this is the contract which the Guardians observe and which fundamentally allows for multichain communication.
- **Transaction logs**: Blockchain-specific logs that allow the Guardians to observe messages emitted by the Core Contract.
## Off-Chain Components
- **Guardian Network**: Validators that exist in their own P2P network. Guardians observe and validate the messages emitted by the Core Contract on each supported chain to produce VAAs (signed messages).
- **[Guardian](/docs/protocol/infrastructure/guardians/){target=\_blank}**: One of 19 validators in the Guardian Network that contributes to the VAA multisig.
- **[Spy](/docs/protocol/infrastructure/spy/){target=\_blank}**: A daemon that subscribes to messages published within the Guardian Network. A Spy can observe and forward network traffic, which helps scale up VAA distribution.
- **[API](https://docs.wormholescan.io/){target=\_blank}**: A REST server to retrieve details for a VAA or the Guardian Network.
- **[VAAs](/docs/protocol/infrastructure/vaas/){target=\_blank}**: Verifiable Action Approvals (VAAs) are the signed attestation of an observed message from the Wormhole Core Contract.
- **[Relayer](/docs/protocol/infrastructure/relayer/){target=\_blank}**: Any off-chain process that relays a VAA to the target chain.
- **Wormhole relayers**: A decentralized relayer network that delivers messages that are requested on-chain via the Wormhole relayer contract.
- **Custom relayers**: Relayers that only handle VAAs for a specific protocol or multichain application. They can execute custom logic off-chain, reducing gas costs and increasing multichain compatibility. Currently, multichain application developers are responsible for developing and hosting custom relayers.
## Next Steps
- :octicons-book-16:{ .lg .middle } **Core Contracts**
---
Discover Wormhole's Core Contracts, enabling multichain communication with message sending, receiving, and multicast features for efficient synchronization.
[:custom-arrow: Explore Core Contracts](/docs/protocol/infrastructure/core-contracts/)
- :octicons-tools-16:{ .lg .middle } **Core Messaging**
---
Follow the guides in this section to work directly with the building blocks of Wormhole messaging, Wormhole-deployed relayers and Core Contracts, to send, receive, validate, and track multichain messages.
[:custom-arrow: Build with Core Messaging](/docs/products/messaging/guides/wormhole-relayers/)
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/ecosystem.md
--- BEGIN CONTENT ---
---
title: Ecosystem
description: Explore Wormhole's modular ecosystem of cross-chain tools for messaging, bridging, governance, and developer integration.
categories: Basics
---
# The Wormhole Ecosystem
[Wormhole](/docs/protocol/introduction/){target=\_blank} is a cross-chain messaging protocol connecting decentralized applications across multiple blockchains. It offers a suite of interoperability tools, each addressing different multichain challenges, and allows developers to mix and match these products as needed.
Whether you’re looking for a simple UI-based bridging experience, a native token transfer flow without wrapped assets, real-time cross-chain data queries, or an advanced settlement layer for complex asset movements, Wormhole has a product designed for that purpose. Every solution integrates with Wormhole’s core messaging network, ensuring each module can operate independently or in combination with others.
This page will guide you through the structural layout of these tools—how they fit together, can be used independently, and can be layered to build robust, multichain applications.
## Ecosystem Overview
The diagram shows a high-level view of Wormhole’s modular stack, illustrating how different tools are grouped into four layers:
- **Application and user-facing products**: The top layer includes user-centric solutions such as [Connect](/docs/products/connect/overview/){target=\_blank} (a simple bridging interface) and the [NTT Launchpad](https://ntt.wormhole.com/){target=\_blank} (for streamlined native asset deployments).
- **Asset and data transfer layer**: Below it sits the core bridging and data solutions—[NTT](/docs/products/token-transfers/native-token-transfers/overview/){target=\_blank}, [WTT](/docs/products/token-transfers/wrapped-token-transfers/overview/){target=\_blank}, [Queries](/docs/products/queries/overview/){target=\_blank}, [Settlement](/docs/products/settlement/overview/){target=\_blank}, and [MultiGov](/docs/products/multigov/overview/){target=\_blank}—that handle the movement of tokens, real-time data fetching, advanced cross-chain settlements, and cross-chain governance.
- **Integration layer**: The [TypeScript SDK](/docs/tools/typescript-sdk/get-started/){target=\_blank} and [WormholeScan API](https://wormholescan.io/#/){target=\_blank} provide developer-friendly libraries and APIs to integrate cross-chain capabilities into applications.
- **Foundation layer**: At the base, the [Wormhole messaging](/docs/products/messaging/overview/){target=\_blank} system and the [core contracts](/docs/protocol/infrastructure/core-contracts/){target=\_blank} secure the entire network, providing essential verification and cross-chain message delivery.

## Bringing It All Together: Interoperability in Action
Wormhole’s modularity makes it easy to adopt just the pieces you need. If you want to quickly add bridging to a dApp, use Connect at the top layer while relying on the Foundation Layer behind the scenes. Or if your app needs to send raw messages between chains, integrate the Messaging layer directly via the Integration Layer (TypeScript or Solidity SDK). You can even layer on additional features—like real-time data calls from Queries or more flexible bridging flows with Native Token Transfers.
Ultimately, these components aren’t siloed but designed to be combined. You could, for instance, fetch a balance from one chain using Queries and then perform an on-chain swap on another chain using Settlement. Regardless of your approach, each Wormhole product is powered by the same Guardian-secured messaging backbone, ensuring all cross-chain interactions remain reliable and secure.
## Next Steps
Unsure which bridging solution you need? Visit the [Product Comparison](/docs/products/overview/){target=\_blank} page to quickly match your requirements with the right Wormhole tool.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/infrastructure/core-contracts.md
--- BEGIN CONTENT ---
---
title: Core Contracts
description: Discover Wormhole's Core Contracts, which enable multichain communication with message sending, receiving, and multicast features for efficient synchronization.
categories: Basics
---
# Core Contracts
The Wormhole Core Contract is deployed across each supported blockchain network. This contract is a fundamental component of the Wormhole interoperability protocol and acts as the foundational layer enabling secure and efficient multichain messaging. All multichain applications either interact directly with the Core Contract or with another contract that does.
This page summarizes the key functions of the Core Contract and outlines how the Core Contract works.
## Key Functions
Key functions of the Wormhole Core Contract include the following:
- **Multichain messaging**: Standardizes and secures the format of messages to facilitate consistent communication for message transfer between Wormhole-connected blockchain networks, allowing developers to leverage the unique features of each network.
- **Verification and validation**: Verifies and validates all VAAs received on the target chain by confirming the Guardian signature to ensure the message is legitimate and has not been manipulated or altered.
- **Guardian Network coordination**: Coordinates with Wormhole's Guardian Network to facilitate secure, trustless communication across chains and ensure that only validated interactions are processed to enhance the protocol's overall security and reliability.
- **Event emission for monitoring**: Emits events for every multichain message processed, allowing for network activity monitoring like tracking message statuses, debugging, and applications that can react to multichain events in real time.
## How the Core Contract Works
The Wormhole Core Contract is central in facilitating secure and efficient multichain transactions. It enables communication between different blockchain networks by packaging transaction data into standardized messages, verifying their authenticity, and ensuring they are executed correctly on the destination chain.
The following describes the role of the Wormhole Core Contract in message transfers:
1. **Message submission**: When a user initiates a multichain transaction, the Wormhole Core Contract on the source chain packages the transaction data into a standardized message payload and submits it to the Guardian Network for verification.
2. **Guardian verification**: The Guardians independently observe and sign the message. Once enough Guardians have signed the message, the collection of signatures is combined with the message and metadata to produce a VAA.
3. **Message reception and execution**: On the target chain, the Wormhole Core Contract receives the verified message, checks the Guardians' signatures, and executes the corresponding actions like minting tokens, updating states, or calling specific smart contract functions.
For a closer look at how messages flow between chains and all of the components involved, you can refer to the [Architecture Overview](/docs/protocol/architecture/) page.
### Message Submission
You can send multichain messages by calling a function against the source chain Core Contract, which then publishes the message. Message publishing strategies can differ by chain; however, generally, the Core Contract posts the following items to the blockchain logs:
- **`emitterAddress`**: The contract which made the call to publish the message.
- **`sequenceNumber`**: A unique number that increments for every message for a given emitter (and implicitly chain).
- **`consistencyLevel`**: The level of finality to reach before the Guardians will observe and attest the emitted event. This is a defense against reorgs and rollbacks since a transaction, once considered "final," is guaranteed not to have the state changes it caused rolled back. Since different chains use different consensus mechanisms, each one has different finality assumptions, so this value is treated differently on a chain-by-chain basis. See the options for finality for each chain in the [Wormhole Finality](/docs/products/reference/consistency-levels/){target=\_blank} reference page.
There are no fees to publish a message except when publishing on Solana, but this is subject to change in the future.
### Message Reception
When you receive a multichain message on the target chain Core Contract, you generally must parse and verify the [components of a VAA](/docs/protocol/infrastructure/vaas#vaa-format){target=\_blank}. Receiving and verifying a VAA ensures that the Guardian Network properly attests to the message and maintains the integrity and authenticity of the data transmitted between chains.
## Multicast
Multicast refers to simultaneously broadcasting a single message or transaction across different blockchains with no destination address or chain for the sending and receiving functions. VAAs attest that "this contract on this chain said this thing." Therefore, VAAs are multicast by default and will be verified as authentic on any chain where they are used.
This multicast-by-default model makes it easy to synchronize state across the entire ecosystem. A blockchain can make its data available to every chain in a single action with low latency, which reduces the complexity of the n^2 problems encountered by routing data to many blockchains.
This doesn't mean an application _cannot_ specify a destination address or chain. For example, the [Wrapped Token Transfers (WTT)](/docs/products/token-transfers/wrapped-token-transfers/overview/){target=\_blank} and [Wormhole relayer](/docs/protocol/infrastructure/relayer/){target=\_blank} contracts require that some destination details be passed and verified on the destination chain.
Because the VAA creation is separate from relaying, the multicast model does not incur an additional cost when a single chain is targeted. If the data isn't needed on a certain blockchain, don't relay it there, and it won't cost anything.
## Next Steps
- :octicons-book-16:{ .lg .middle } **Verified Action Approvals (VAA)**
---
Learn about Verified Action Approvals (VAAs) in Wormhole, their structure, validation, and their role in multichain communication.
[:custom-arrow: Learn About VAAs](/docs/protocol/infrastructure/vaas/)
- :octicons-tools-16:{ .lg .middle } **Get Started with Core Contracts**
---
This guide walks through the key methods of the Core Contracts, providing you with the knowledge needed to integrate them into your multichain contracts.
[:custom-arrow: Build with Core Contracts](/docs/products/messaging/guides/core-contracts/)
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--- BEGIN CONTENT ---
---
title: Guardians
description: Explore Wormhole's Guardian Network, a decentralized system for secure, scalable cross-chain communication across various blockchain ecosystems.
categories: Basics
---
# Guardians
Wormhole relies on a set of 19 distributed nodes that monitor the state on several blockchains. In Wormhole, these nodes are referred to as Guardians. The current Guardian set can be seen in the [Dashboard](https://wormhole-foundation.github.io/wormhole-dashboard/#/?endpoint=Mainnet){target=\_blank}.
Guardians fulfill their role in the messaging protocol as follows:
1. Each Guardian observes messages and signs the corresponding payloads in isolation from the other Guardians.
2. Guardians combine their independent signatures to form a multisig.
3. This multisig represents proof that a majority of the Wormhole network has observed and agreed upon a state.
Wormhole refers to these multisigs as [Verifiable Action Approvals](/docs/protocol/infrastructure/vaas/){target=\_blank} (VAAs).
## Guardian Network
The Guardian Network functions as Wormhole's decentralized oracle, ensuring secure, cross-chain interoperability. Learning about this critical element of the Wormhole ecosystem will help you better understand the protocol.
The Guardian Network is designed to help Wormhole deliver on five key principles:
- **Decentralization**: Control of the network is distributed across many parties.
- **Modularity**: Independent components (e.g., oracle, relayer, applications) ensure flexibility and upgradeability.
- **Chain agnosticism**: Supports EVM, Solana, and other blockchains without relying on a single network.
- **Scalability**: Can handle large transaction volumes and high-value transfers.
- **Upgradeable**: Can change the implementation of its existing modules without breaking integrators to adapt to changes in decentralized computing.
The following sections explore each principle in detail.
### Decentralization
Decentralization remains the core concern for interoperability protocols. Earlier solutions were fully centralized, and even newer models often rely on a single entity or just one or two actors, creating low thresholds for collusion or failure.
Two common approaches to decentralization have notable limitations:
- **Proof-of-Stake (PoS)**: While PoS is often seen as a go-to model for decentralization, it's not well-suited for a network that verifies many blockchains and doesn't run its own smart contracts. Its security in this context is unproven, and it introduces complexities that make other design goals harder to achieve.
- **Zero-Knowledge Proofs (ZKPs)**: ZKPs offer a trustless and decentralized approach, but the technology is still early-stage. On-chain verification is often too computationally expensive—especially on less capable chains—so a multisig-based fallback is still required for practical deployment.
In the current De-Fi landscape, most major blockchains are secured by a small group of validator companies. Only a limited number of companies worldwide have the expertise and capital to run high-performance validators.
If a protocol could unite many of these top validator companies into a purpose-built consensus mechanism designed for interoperability, it would likely offer better performance and security than a token-incentivized network. The key question is: how many of them could Wormhole realistically involve?
To answer that, consider these key constraints and design decisions:
- **Threshold signatures allow flexibility, but**: With threshold signatures, in theory, any number of validators could participate. However, threshold signatures are not yet widely supported across blockchains. Verifying them is expensive and complex, especially in a chain-agnostic system.
- **t-Schnorr multisig is more practical**: Wormhole uses [t-Schnorr multisig](https://en.wikipedia.org/wiki/Schnorr_signature){target=\_blank}, which is broadly supported and relatively inexpensive to verify. However, verification costs scale linearly with the number of signers, so the size of the validator set needs to be carefully chosen.
- **19 validators is the optimal tradeoff**: A set of 19 participants presents a practical compromise between decentralization and efficiency. With a two-thirds consensus threshold, only 13 signatures must be verified on-chain—keeping gas costs reasonable while ensuring strong security.
- **Security through reputation, not tokens**: Wormhole relies on a network of established validator companies instead of token-based incentives. These 19 Guardians are among the most trusted operators in the industry—real entities with a track record, not anonymous participants.
This forms the foundation for a purpose-built Proof-of-Authority (PoA) consensus model, where each Guardian has an equal stake. As threshold signatures gain broader support, the set can expand. Once ZKPs become widely viable, the network can evolve into a fully trustless system.
### Modularity
Wormhole is designed with simple components that are very good at a single function. Separating security and consensus (Guardians) from message delivery ([relayers](/docs/protocol/infrastructure/relayer/){target=\_blank}) allows for the flexibility to change or upgrade one component without disrupting the others.
### Chain Agnosticism
Today, Wormhole supports a broader range of ecosystems than any other interoperability protocol because it uses simple tech (t-schnorr signatures), an adaptable, heterogeneous relayer model, and a robust validator network. Wormhole can expand to new ecosystems as quickly as a [Core Contract](/docs/protocol/infrastructure/core-contracts/){target=\_blank} can be developed for the smart contract runtime.
### Scalability
Wormhole scales well, as demonstrated by its ability to handle substantial total value locked (TVL) and transaction volume even during tumultuous events.
Every Guardian must run a full node for every blockchain in the ecosystem. This requirement can be computationally heavy to set up; however, once all the full nodes are running, the Guardian Network's actual computation needs become lightweight.
Performance is generally limited by the speed of the underlying blockchains, not the Guardian Network itself.
### Upgradeable
Wormhole is designed to adapt and evolve in the following ways:
- **Guardian Set expansion**: Future updates may introduce threshold signatures to allow for more Guardians in the set.
- **ZKP integration**: As Zero-Knowledge Proofs become more widely supported, the network can transition to a fully trustless model.
These principles combine to create a clear pathway towards a fully trustless interoperability layer that spans decentralized computing.
## Next Steps
- :octicons-book-16:{ .lg .middle } **Relayers**
---
Discover the role of relayers in the Wormhole network, including client-side, custom, and Wormhole-deployed types, for secure cross-chain communication.
[:custom-arrow: Learn About Relayers](/docs/protocol/infrastructure/relayer/)
- :octicons-tools-16:{ .lg .middle } **Query Guardian Data**
---
Learn how to use Wormhole Queries to add real-time access to Guardian-attested on-chain data via a REST endpoint to your dApp, enabling secure cross-chain interactions and verifications.
[:custom-arrow: Build with Queries](/docs/products/queries/overview/)
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--- BEGIN CONTENT ---
---
title: Relayers
description: Discover the role of relayers in the Wormhole network, including client-side, custom, and Wormhole-deployed types, for secure cross-chain communication.
categories: Basics
---
# Relayers
This page provides a comprehensive guide to relayers within the Wormhole network, describing their role, types, and benefits in facilitating cross-chain processes.
Relayers in the Wormhole context are processes that deliver [Verified Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank} to their destination, playing a crucial role in Wormhole's security model. They can't compromise security, only availability, and act as delivery mechanisms for VAAs without the capacity to tamper with the outcome.
There are three primary types of relayers discussed:
- **Client-side relaying**: A cost-efficient, no-backend-infrastructure approach relying on user-facing front ends. It provides a simple solution, although it can complicate the user experience due to the manual steps involved.
- **Custom relayers**: Backend components that handle parts of the cross-chain process, offering a smoother user experience and allowing off-chain calculations to reduce gas costs. These relayers could operate through direct listening to the Guardian Network (Spy relaying).
- **Wormhole-deployed relayers**: A decentralized relayer network that can deliver arbitrary VAAs, reducing the developer's need to develop, host, or maintain relayers. However, they require all calculations to be done on-chain and might be less gas-efficient.
## Fundamentals
This section highlights the crucial principles underpinning the operation and handling of relayers within the Wormhole network.
Relayers are fundamentally trustless entities within the network, meaning while they don't require your trust to operate, you also shouldn't trust them implicitly. Relayers function as delivery mechanisms, transporting VAAs from their source to their destination.
Key characteristics of VAAs include:
- Public emission from the Guardian Network.
- Authentication through signatures from the Guardian Network.
- Verifiability by any entity or any Wormhole Core Contract.
These characteristics mean anyone can pick up a VAA and deliver it anywhere, but no one can alter the VAA content without invalidating the signatures.
Keep in mind the following security considerations around relayers:
- **Trusting information**: It is crucial not to trust information outside your contract or a VAA. Relying on information from a relayer could expose you to input attacks.
- **Gas optimization**: Using relayers to perform trustless off-chain computation to pass into the destination contract can optimize gas costs but also risk creating attack vectors if not used correctly.
- **Deterministic by design**: The design of a relayer should ensure a single, deterministic way to process messages in your protocol. Relayers should have a "correct" implementation, mirroring "crank turner" processes used elsewhere in blockchain.
## Client-Side Relaying
Client-side relaying relies on user-facing front ends, such as a webpage or a wallet, to complete the cross-chain process.
### Key Features
- **Cost-efficiency**: Users only pay the transaction fee for the second transaction, eliminating any additional costs.
- **No backend infrastructure**: The process is wholly client-based, eliminating the need for a backend relaying infrastructure.
### Implementation
Users themselves carry out the three steps of the cross-chain process:
1. Perform an action on chain A.
2. Retrieve the resulting VAA from the Guardian Network.
3. Perform an action on chain B using the VAA.
### Considerations
Though simple, this type of relaying is generally not recommended if your aim is a highly polished user experience. It can, however, be useful for getting a Minimum Viable Product (MVP) up and running.
- Users must sign all required transactions with their own wallet.
- Users must have funds to pay the transaction fees on every chain involved.
- The user experience may be cumbersome due to the manual steps involved.
## Custom Relayers
Custom relayers are purpose-built components within the Wormhole protocol, designed to relay messages for specific applications. They can perform off-chain computations and can be customized to suit a variety of use cases.
The main method of setting up a custom relayer is by listening directly to the Guardian Network via a [Spy](/docs/protocol/infrastructure/spy/).
### Key Features
- **Optimization**: Capable of performing trustless off-chain computations which can optimize gas costs.
- **Customizability**: Allows for specific strategies like batching, conditional delivery, multi-chain deliveries, and more.
- **Incentive structure**: Developers have the freedom to design an incentive structure suitable for their application.
- **Enhanced UX**: The ability to retrieve a VAA from the Guardian Network and perform an action on the target chain using the VAA on behalf of the user can simplify the user experience.
### Implementation
A plugin relayer to make the development of custom relayers easier is available in the [main Wormhole repository](https://github.com/wormhole-foundation/wormhole/tree/main/relayer){target=\_blank}. This plugin sets up the basic infrastructure for relaying, allowing developers to focus on implementing the specific logic for their application.
### Considerations
Remember, despite their name, custom relayers still need to be considered trustless. VAAs are public and can be submitted by anyone, so developers shouldn't rely on off-chain relayers to perform any computation considered "trusted."
- Development work and hosting of relayers are required.
- The fee-modeling can become complex, as relayers are responsible for paying target chain fees.
- Relayers are responsible for availability, and adding dependencies for the cross-chain application.
## Wormhole Relayers
Wormhole relayers are a component of a decentralized network in the Wormhole protocol. They facilitate the delivery of VAAs to recipient contracts compatible with the standard relayer API.
### Key Features
- **Lower operational costs**: No need to develop, host, or maintain individual relayers.
- **Simplified integration**: Because there is no need to run a relayer, integration is as simple as calling a function and implementing an interface.
### Implementation
The Wormhole relayer integration involves two key steps:
- **Delivery request**: Request delivery from the ecosystem Wormhole relayer contract.
- **Relay reception**: Implement a [`receiveWormholeMessages`](https://github.com/wormhole-foundation/wormhole-solidity-sdk/blob/bacbe82e6ae3f7f5ec7cdcd7d480f1e528471bbb/src/interfaces/IWormholeReceiver.sol#L44-L50){target=\_blank} function within their contracts. This function is invoked upon successful relay of the VAA.
### Considerations
Developers should note that the choice of relayers depends on their project's specific requirements and constraints. Wormhole relayers offer simplicity and convenience but limit customization and optimization opportunities compared to custom relayers.
- All computations are performed on-chain.
- Potentially less gas-efficient compared to custom relayers.
- Optimization features like conditional delivery, batching, and off-chain calculations might be restricted.
- Support may not be available for all chains.
## Next Steps
- :octicons-book-16:{ .lg .middle } **Spy**
---
Discover Wormhole's Spy daemon, which subscribes to gossiped messages in the Guardian Network, including VAAs and Observations, with setup instructions.
[:custom-arrow: Learn More About the Spy](/docs/protocol/infrastructure/spy/)
- :octicons-book-16:{ .lg .middle } **Build with Wormhole Relayers**
---
Learn how to use Wormhole-deployed relayer configurations for seamless cross-chain messaging between contracts on different EVM blockchains without off-chain deployments.
[:custom-arrow: Get Started with Wormhole Relayers](/docs/products/messaging/guides/wormhole-relayers/)
- :octicons-book-16:{ .lg .middle } **Run a Custom Relayer**
---
Learn how to build and configure your own off-chain custom relaying solution to relay Wormhole messages for your applications using the Relayer Engine.
[:custom-arrow: Get Started with Custom Relayers](/docs/protocol/infrastructure-guides/run-relayer/)
--- END CONTENT ---
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--- BEGIN CONTENT ---
---
title: Spy
description: Discover Wormhole's Spy daemon, which subscribes to gossiped messages in the Guardian Network, including VAAs and Observations, with setup instructions.
categories: Basics
---
# Spy
In Wormhole's ecosystem, the _Spy_ is a daemon, a continuously running background process that monitors messages within the Guardian Network. Unlike Guardians, a Spy doesn't perform validation; instead, it serves as an interface for observing the network's message traffic, enabling applications and users to access live data transmitted over Wormhole.
The primary purpose of a Spy is to subscribe to the gossiped messages across the Guardian Network, tracking key message types that allow integrators and applications to monitor real-time network activity without directly engaging in consensus operations.
This page provides a comprehensive guide to where the Spy fits within the Wormhole network, describing the key features and role in facilitating multichain processes.
## Key Features
- **Real-time monitoring of Wormhole messages**: The Spy allows users to observe Wormhole messages as they are published across supported chains in near real-time.
- **Filterable and observable message streams**: Users can filter message streams by chain, emitter, and other criteria, making it easier to track specific contracts or categories of interest.
- **Integration-friendly event streaming**: The Spy exposes gRPC and WebSocket interfaces, making it easy to integrate message observation into custom tooling, dashboards, or indexing services.
- **Support for multiple message protocols**: It can observe messages from different Wormhole messaging protocols (WTT, CCTP, NTT, etc.), providing broad coverage of cross-chain activity.
- **Lightweight and infrastructure-ready**: The Spy is designed to run as part of indexing or backend services, not requiring validator-level infrastructure.
## Integrator Use Case
The Spy provides a valuable mechanism for integrators to observe real-time network activity in the Guardian Network without directly engaging in validation or consensus. By running a Spy, integrators can track multichain events and message flows — such as VAAs, observations, and Guardian heartbeats — to monitor network activity essential to their applications.
This monitoring capability is especially beneficial for applications that need immediate insights into multichain data events. Integrators can run a Spy to ensure their applications are promptly informed of message approvals, observations, or Guardian liveness signals, supporting timely and responsive app behavior without additional overhead on network resources.
## Observable Message Categories
A Spy can access the following categories of messages shared over the gossip protocol:
- **[Verifiable Action Approvals (VAAs)](/docs/protocol/infrastructure/vaas/){target=\_blank}**: Packets of multichain data.
- The Spy can detect whether a VAA has been approved by the Guardian Network, making it a valuable tool for applications needing real-time multichain verification.
- **[Observations](/docs/products/reference/glossary/#observation){target=\_blank}**: Emitted by Wormhole's core contracts, observations are picked up by the Guardians and relayed across the network.
- A Spy allow users to monitor these messages, adding transparency and insight into blockchain events.
- **[Guardian heartbeats](/docs/products/reference/glossary/#heartbeat){target=\_blank}**: Heartbeat messages represent Guardian node status.
- By monitoring heartbeats, a Spy can signal the liveness and connectivity of Guardians in the network.
## Additional Resources
- :octicons-code-16:{ .lg .middle } **Spy Source Code**
---
To see the source code for the Go implementation of the Spy, visit the `wormhole` repository on GitHub.
[:custom-arrow: View the Source Code](https://github.com/wormhole-foundation/wormhole/blob/main/node/cmd/spy/spy.go){target=\_blank}
- :octicons-code-16:{ .lg .middle } **Alternative Implementation**
---
Visit the `beacon` repository on GitHub to learn more about Beacon, an alternative highly available, reduced-latency version of the Wormhole Spy.
[:custom-arrow: Get Started with Pyth Beacon](https://github.com/pyth-network/beacon)
- :octicons-book-16:{ .lg .middle } **Discover Wormhole Queries**
---
For an alternative option to on-demand access to Guardian-attested multichain data, see the Wormhole Queries page. Queries provide a simple, REST endpoint style developer experience.
[:custom-arrow: Explore Queries](/docs/products/queries/overview/)
## Next Steps
- :octicons-code-16:{ .lg .middle } **Run a Spy**
---
Learn how to run the needed infrastructure to spin up a Spy daemon locally and subscribe to a stream of Verifiable Action Approvals (VAAs).
[:custom-arrow: Spin Up a Spy](/docs/protocol/infrastructure-guides/run-spy/){target=\_blank}
- :octicons-code-16:{ .lg .middle } **Use Queries**
---
For access to real-time network data without infrastructure overhead, follow this guide and use Wormhole Query to construct a query, make a request, and verify the response.
[:custom-arrow: Get Started with Queries](/docs/products/queries/guides/use-queries/)
--- END CONTENT ---
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--- BEGIN CONTENT ---
---
title: VAAs
description: Learn about Verified Action Approvals (VAAs) in Wormhole, their structure, validation, and role in cross-chain communication.
categories: Basics
---
# Verified Action Approvals
Verified Action Approvals (VAAs) are Wormhole's core messaging primitive. They are packets of cross-chain data emitted whenever a cross-chain application contract interacts with the Core Contract.
[Guardians](/docs/protocol/infrastructure/guardians/){target=\_blank} validate messages emitted by contracts before sending them to the target chain. Once a majority of Guardians agree the message is valid, they sign a keccak256 hash of the message body.
The message is wrapped up in a structure called a VAA, which combines the message with the Guardian signatures to form a proof.
VAAs are uniquely indexed by the (`emitter_chain`, `emitter_address`, `sequence`) tuple. To obtain a VAA, one can query the [Wormholescan API](https://docs.wormholescan.io/){target=\_blank} with this information.
The `sequence` field depends on the final ordering of blocks on the emitter chain. When a lower consistency level is chosen (i.e., not waiting for finality), there is a chance that chain reorganizations could lead to multiple, different VAAs appearing for what looks like the “same” message on the user side.
The tuple (`emitter_chain`, `emitter_address`, `sequence`) can only be considered unique if the chain does not undergo a reorg and the block containing the message has effectively reached finality. However, there is always a small chance of an extended reorg that could invalidate or alter a previously emitted sequence number.
## VAA Format
The basic VAA consists of header and body components described as follows:
- **Header**: Holds metadata about the current VAA, the Guardian set that is currently active, and the list of signatures gathered so far.
- **`version` ++"byte"++**: The VAA Version.
- **`guardian_set_index` ++"u32"++**: Indicates which Guardian set is signing.
- **`len_signatures` ++"u8"++**: The number of signatures stored.
- **`signatures` ++"[]signature"++**: The collection of Guardian signatures.
Where each `signature` is:
- **`index` ++"u8"++**: The index of this Guardian in the Guardian set.
- **`signature` ++"[65]byte"++**: The ECDSA signature.
- **Body**: _deterministically_ derived from an on-chain message. Any two Guardians processing the same message must derive the same resulting body to maintain a one-to-one relationship between VAAs and messages to avoid double-processing messages.
- **`timestamp` ++"u32"++**: The timestamp of the block this message was published in.
- `nonce` ++"u32"++.
- **`emitter_chain` ++"u16"++**: The id of the chain that emitted the message.
- **`emitter_address` ++"[32]byte"++**: The contract address (Wormhole formatted) that called the Core Contract.
- **`sequence` ++"u64"++**: The auto-incrementing integer that represents the number of messages published by this emitter.
- **`consistency_level` ++"u8"++**: The consistency level (finality) required by this emitter.
- **`payload` ++"[]byte"++**: Arbitrary bytes containing the data to be acted on.
The deterministic nature of the body is only strictly true once the chain's state is finalized. If a reorg occurs, and a transaction that previously appeared in block X is replaced by block Y, Guardians observing different forks may generate different VAAs for what the emitter contract believes is the same message. This scenario is less likely once a block is sufficiently buried, but it can still happen if you choose a faster (less finalized) consistency level
The body contains relevant information for entities, such as contracts or other systems, that process or utilize VAAs. When a function like `parseAndVerifyVAA` is called, the body is returned, allowing verification of the `emitterAddress` to determine if the VAA originated from a trusted contract.
Because VAAs have no destination, they are effectively multicast. Any Core Contract on any chain in the network will verify VAAs as authentic. If a VAA has a specific destination, relayers are responsible for appropriately completing that delivery.
## Consistency and Finality
The consistency level determines whether Guardians wait for a chain's final commitment state or issue a VAA sooner under less-final conditions. This choice is especially relevant for blockchains without instant finality, where the risk of reorganization remains until a block is deeply confirmed.
Guardian watchers are specialized processes that monitor each blockchain in real-time. They enforce the selected consistency level by deciding whether enough commitment has been reached before signing and emitting a VAA. Some chains allow only one commitment level (effectively final), while others let integrators pick between near-final or fully finalized states. Choosing a faster option speeds up VAA production but increases reorg risk. A more conservative option takes longer but reduces the likelihood of rollback.
## Signatures
The body of the VAA is hashed twice with `keccak256` to produce the signed digest message.
```js
// hash the bytes of the body twice
digest = keccak256(keccak256(body))
// sign the result
signature = ecdsa_sign(digest, key)
```
!!!tip "Hash vs. double hash"
Different implementations of the ECDSA signature validation may apply a keccak256 hash to the message passed, so care must be taken to pass the correct arguments.
For example, the [Solana secp256k1 program](https://solana.com/docs/core/programs#secp256k1-program){target=\_blank} will hash the message passed. In this case, the argument for the message should be a single hash of the body, not the twice-hashed body.
## Payload Types
Different applications built on Wormhole may specify a format for the payloads attached to a VAA. This payload provides information on the target chain and contract so it can take action (e.g., minting tokens to a receiver address).
### Token Transfer
Many bridges use a lockup/mint and burn/unlock mechanism to transfer tokens between chains. Wormhole's generic message-passing protocol handles the routing of lock and burn events across chains to ensure Wormhole's Wrapped Token Transfer (WTT) is chain-agnostic and can be rapidly integrated into any network with a Wormhole contract.
Transferring tokens from the sending chain to the destination chain requires the following steps:
1. Lock the token on the sending chain.
2. The sending chain emits a message as proof the token lockup is complete.
3. The destination chain receives the message confirming the lockup event on the sending chain.
4. The token is minted on the destination chain.
The message the sending chain emits to verify the lockup is referred to as a transfer message and has the following structure:
- **`payload_id` ++"u8"++**: The ID of the payload. This should be set to `1` for a token transfer.
- **`amount` ++"u256"++**: Amount of tokens being transferred.
- **`token_address` ++"u8[32]"++**: Address on the source chain.
- **`token_chain` ++"u16"++**: Numeric ID for the source chain.
- **`to` ++"u8[32]"++**: Address on the destination chain.
- **`to_chain` ++"u16"++**: Numeric ID for the destination chain.
- **`fee` ++"u256"++**: Portion of amount paid to a relayer.
This structure contains everything the destination chain needs to learn about a lockup event. Once the destination chain receives this payload, it can mint the corresponding asset.
Note that the destination chain is agnostic regarding how the tokens on the sending side were locked. They could have been burned by a mint or locked in a custody account. The protocol relays the event once enough Guardians have attested to its existence.
### Attestation
While the destination chain can trust the message from the sending chain to inform it of token lockup events, it has no way of verifying the correct token is locked up. To solve this, WTT supports token attestation.
To create a token attestation, the sending chain emits a message containing metadata about a token, which the destination chain may use to preserve the name, symbol, and decimal precision of a token address.
The message format for token attestation is as follows:
- **`payload_id` ++"u8"++**: The ID of the payload. This should be set to `2` for an attestation.
- **`token_address` ++"[32]byte"++**: Address of the originating token contract.
- **`token_chain` ++"u16"++**: Chain ID of the originating token.
- **`decimals` ++"u8"++**: Number of decimals this token should have.
- **`symbol` ++"[32]byte"++**: Short name of asset.
- **`name` ++"[32]byte"++**: Full name of asset.
#### Attestation Tips
Be aware of the following considerations when working with attestations:
- Attestations use a fixed-length byte array to encode UTF8 token name and symbol data. Because the byte array is fixed length, the data contained may truncate multibyte Unicode characters.
- When sending an attestation VAA, it is recommended to send the longest UTF8 prefix that doesn't truncate a character and then right-pad it with zero bytes.
- When parsing an attestation VAA, it is recommended to trim all trailing zero bytes and convert the remainder to UTF-8 via any lossy algorithm.
- Be mindful that different on-chain systems may have different VAA parsers, resulting in different names/symbols on different chains if the string is long or contains invalid UTF8.
- Without knowing a token's decimal precision, the destination chain cannot correctly mint the number of tokens when processing a transfer. For this reason, WTT requires an attestation for each token transfer.
### Token Transfer with Message
The Token Transfer with Message data structure is identical to the token-only data structure, except for the following:
- **`fee` field**: Replaced with the `from_address` field.
- **`payload` field**: Is added containing arbitrary bytes. A dApp may include additional data in this arbitrary byte field to inform some application-specific behavior.
This VAA type was previously known as Contract Controlled Transfer and is also sometimes referred to as a `payload3` message. The Token Transfer with Message data sructure is as follows:
- **`payload_id` ++"u8"++**: The ID of the payload. This should be set to `3` for a token transfer with message.
- **`amount` ++"u256"++**: Amount of tokens being transferred.
- **`token_address` ++"u8[32]"++**: Address on the source chain.
- **`token_chain` ++"u16"++**: Numeric ID for the source chain.
- **`to` ++"u8[32]"++**: Address on the destination chain.
- **`to_chain` ++"u16"++**: Numeric ID for the destination chain.
- **`from_address` ++"u8[32]"++**: Address that called WTT on the source chain.
- **`payload` ++"[]byte"++**: Message, arbitrary bytes, app-specific.
### Governance
Governance VAAs don't have a `payload_id` field like the preceding formats. Instead, they trigger an action in the deployed contracts (for example, an upgrade).
#### Action Structure
Governance messages contain pre-defined actions, which can target the various Wormhole modules currently deployed on-chain. The structure includes the following fields:
- **`module` ++"u8[32]"++**: Contains a right-aligned module identifier.
- **`action` ++"u8"++**: Predefined governance action to execute.
- **`chain` ++"u16"++**: Chain the action is targeting. This should be set to `0` for all chains.
- **`args` ++"any"++**: Arguments to the action.
Below is an example message containing a governance action triggering a code upgrade to the Solana Core Contract. The module field here is a right-aligned encoding of the ASCII Core, represented as a 32-byte hex string.
```js
module: 0x0000000000000000000000000000000000000000000000000000436f7265
action: 1
chain: 1
new_contract: 0x348567293758957162374959376192374884562522281937446234828323
```
#### Actions
The meaning of each numeric action is pre-defined and documented in the Wormhole design documents. For each application, the relevant definitions can be found via these links:
- [Core governance actions](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0002_governance_messaging.md){target=\_blank}
- [WTT governance actions](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0003_token_bridge.md){target=\_blank}
## Lifetime of a Message
Anyone can submit a VAA to the target chain. Guardians typically don't perform this step to avoid transaction fees. Instead, applications built on top of Wormhole can acquire a VAA via the Guardian RPC and submit it in a separate flow.
With the concepts now defined, it is possible to illustrate a full flow for message passing between two chains. The following stages demonstrate each step of processing that the Wormhole network performs to route a message.
1. **A message is emitted by a contract running on Chain A**: Any contract can emit messages, and the Guardians are programmed to observe all chains for these events. Here, the Guardians are represented as a single entity to simplify the graphics, but the observation of the message must be performed individually by each of the 19 Guardians.
2. **Signatures are aggregated**: Guardians independently observe and sign the message. Once enough Guardians have signed the message, the collection of signatures is combined with the message and metadata to produce a VAA.
3. **VAA submitted to target chain**: The VAA acts as proof that the Guardians have collectively attested the existence of the message payload. The VAA is submitted (or relayed) to the target chain to be processed by a receiving contract and complete the final step.

## Next Steps
- :octicons-book-16:{ .lg .middle } **Guardians**
---
Explore Wormhole's Guardian Network, a decentralized system for secure, scalable cross-chain communication across various blockchain ecosystems.
[:custom-arrow: Learn About Guardians](/docs/protocol/infrastructure/guardians/)
- :octicons-tools-16:{ .lg .middle } **Wormhole Relayer**
---
Explore this guide to using Wormhole-deployed relayers to send and receive messages using VAAs.
[:custom-arrow: Build with Wormhole Relayer](/docs/products/messaging/guides/wormhole-relayers/)
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/introduction.md
--- BEGIN CONTENT ---
---
title: Introduction to Wormhole
description: Wormhole is a protocol for seamless communication between blockchains, enabling cross-chain applications and integrations.
categories: Basics
---
# Introduction to Wormhole
In the rapidly evolving landscape of blockchain technology, interoperability between different blockchains remains a significant challenge. Developers often face hurdles in creating applications that can seamlessly operate across multiple blockchains, limiting innovation and the potential of decentralized ecosystems.
Wormhole addresses this problem by providing a _generic message-passing_ protocol that enables secure and efficient communication between blockchains. By allowing data and asset transfers across various blockchain networks, Wormhole breaks down the walls that traditionally separate these ecosystems.
Wormhole is distinguished by its focus on robust security, scalability, and transparency. The protocol is supported by a decentralized network of validators that ensure the integrity of every cross-chain transaction. This, combined with Wormhole’s proven performance in real-world applications, gives developers a dependable platform to create and scale multichain applications confidently.

!!! note
The above is an oversimplified illustration of the protocol; details about the architecture and components are available on the [architecture page](/docs/protocol/architecture/){target=\_blank}.
Wormhole allows developers to leverage the strengths of multiple blockchain ecosystems without being confined to one. This means applications can benefit from the unique features of various networks—such as Solana's high throughput, Ethereum's security, and Cosmos's interoperability while maintaining a unified, efficient user experience.
This page introduces the key concepts and components necessary to understand how Wormhole enables fast, secure, and scalable cross-chain communication.
## What Problems Does Wormhole Solve?
Interoperability is a critical challenge in the rapidly evolving blockchain landscape. Individual blockchains are often isolated, limiting the potential for integrated applications operating across multiple ecosystems. Wormhole solves this problem by enabling seamless communication between blockchains, allowing developers to create multichain applications that can leverage the unique features of each network.
Critical problems Wormhole addresses include:
- **Blockchain isolation**: Wormhole connects disparate blockchains, enabling the transfer of assets, data, and governance actions across networks.
- **Cross-chain complexity**: By abstracting the complexities of cross-chain communication, Wormhole makes it easier for developers to build and deploy cross-chain applications.
- **Security and decentralization**: Wormhole prioritizes security through a decentralized Guardian network that validates and signs messages, ensuring the integrity of cross-chain interactions.
## What Does Wormhole Offer?
Wormhole provides a suite of tools and protocols that support a wide range of use cases:
- **Cross-chain messaging**: Securely transfer arbitrary data between blockchains, enabling the development of cross-chain decentralized applications.
- **Asset transfers**: Facilitate the movement of tokens across supported chains with ease, powered by protocols built on Wormhole like [Portal](https://portalbridge.com/){target=\_blank}.
- **Developer tools**: Leverage Wormhole’s [TypeScript SDK](/docs/tools/typescript-sdk/get-started/){target=\_blank}, [Wormholescan](https://wormholescan.io/){target=\_blank}, and the [Wormholescan API](https://wormholescan.io/#/developers/api-doc){target=\_blank} and documentation to build and deploy cross-chain applications quickly and efficiently.
## What Isn't Wormhole?
- **Wormhole is _not_ a blockchain**: It acts as a communication layer that connects different blockchains, enabling them to interact without being a blockchain itself.
- **Wormhole is _not_ a token bridge**: While it facilitates token transfers, Wormhole also supports a wide range of cross-chain applications, making it much more versatile than a typical bridge.
## Use Cases of Wormhole
Consider the following examples of potential applications enabled by Wormhole:
- **Cross-chain exchange**: Using [Wormhole Connect](/docs/products/connect/overview/){target=\_blank}, developers can build exchanges that allow deposits from any Wormhole-connected chain, significantly increasing liquidity access.
- [**Cross-chain governance**](https://wormhole.com/blog/stake-for-governance-guide){target=\_blank}: Projects with communities spread across multiple blockchains can use Wormhole to relay votes from each chain to a designated governance chain, enabling unified decision-making through combined proposals.
- **Cross-chain game**: Games can be developed on a performant network like Solana, with rewards issued on another network, such as Ethereum.
## Explore
Discover more about the Wormhole ecosystem, components, and protocols:
- **[Architecture](/docs/protocol/architecture/){target=\_blank}**: Explore the components of the protocol.
- **[Protocol Specifications](https://github.com/wormhole-foundation/wormhole/tree/main/whitepapers){target=\_blank}**: Learn about the protocols built on top of Wormhole.
## Demos
Demos offer more realistic implementations than tutorials:
- **[Wormhole Scaffolding](https://github.com/wormhole-foundation/wormhole-scaffolding){target=\_blank}**: Quickly set up a project with the Scaffolding repository.
- **[Demo Tutorials](https://github.com/wormhole-foundation/demo-tutorials){target=\_blank}**: Explore various demos that showcase Wormhole's capabilities across different blockchains.
!!! note
Wormhole Integration Complete?
Let us know so we can list your project in our ecosystem directory and introduce you to our global, multichain community!
**[Reach out now!](https://forms.clickup.com/45049775/f/1aytxf-10244/JKYWRUQ70AUI99F32Q){target=\_blank}**
## Supported Networks by Product
Wormhole supports a growing number of blockchains. Check out the [Supported Networks by Product](/docs/products/reference/supported-networks/){target=\_blank} page to see which networks are supported for each Wormhole product.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/protocol/security.md
--- BEGIN CONTENT ---
---
title: Security
description: Explore Wormhole's security features, including the Guardian network, governance, monitoring, open-source development, and bug bounty programs.
categories: Basics
---
# Security
## Core Security Assumptions
At its core, Wormhole is secured by a network of [Guardian](/docs/protocol/infrastructure/guardians/){target=\_blank} nodes that validate and sign messages. If a super majority (e.g., 13 out of 19) of Guardians sign the same message, it can be considered valid. A smart contract on the target chain will verify the signatures and format of the message before approving any transaction.
- Wormhole's core security primitive is its signed messages (signed [VAAs](/docs/protocol/infrastructure/vaas/){target=\_blank}).
- The Guardian network is currently secured by a collection of 19 of the world's top [validator companies](https://wormhole-foundation.github.io/wormhole-dashboard/#/?endpoint=Mainnet){target=\_blank}.
- Guardians produce signed state attestations (signed VAAs) when requested by a Core Contract integrator.
- Every Guardian runs full nodes (rather than light nodes) of every blockchain in the Wormhole network, so if a blockchain suffers a consensus attack or hard fork, the blockchain will disconnect from the network rather than potentially produce invalid signed VAAs.
- Any Signed VAA can be verified as authentic by the Core Contract of any other chain.
- [Relayers](/docs/protocol/infrastructure/relayer/){target=\_blank} are considered untrusted in the Wormhole ecosystem.
In summary:
- **Core integrators aren't exposed to risk from chains and contracts they don't integrate with**.
- By default, you only trust Wormhole's signing process and the core contracts of the chains you're on.
- You can expand your contract and chain dependencies as you see fit.
Core assumptions aside, many other factors impact the real-world security of decentralized platforms. Here is more information on additional measures that have been put in place to ensure the security of Wormhole.
## Guardian Network
Wormhole is an evolving platform. While the Guardian set currently comprises 19 validators, this is a limitation of current blockchain technology.
### Governance
Governance is the process through which contract upgrades happen. Guardians manually vote on governance proposals that originate inside the Guardian Network and are then submitted to ecosystem contracts.
This means that governance actions are held to the same security standard as the rest of the system. A two-thirds supermajority of the Guardians is required to pass any governance action.
Governance messages can target any of the various wormhole modules, including the core contracts and all currently deployed Wrapped Token Transfers (WTT) contracts. When a Guardian signs such a message, its signature implies a vote on the action in question. Once more than two-thirds of the Guardians have signed, the message and governance action are considered valid.
All governance actions and contract upgrades have been managed via Wormhole's on-chain governance system.
Via governance, the Guardians can:
- Change the current Guardian set.
- Expand the Guardian set.
- Upgrade ecosystem contract implementations.
The governance system is fully open source in the core repository. See the [Open Source section](#open-source){target=\_blank} for contract source.
## Monitoring
A key element of Wormhole's defense-in-depth strategy is that each Guardian is a highly competent validator company with its own in-house processes for running, monitoring, and securing blockchain operations. This heterogeneous approach to monitoring increases the likelihood that fraudulent activity is detected and reduces the number of single failure points in the system.
Guardians are not just running Wormhole validators; they're running validators for every blockchain inside of Wormhole as well, which allows them to perform monitoring holistically across decentralized computing rather than just at a few single points.
Guardians monitor:
- **Block production and consensus of each blockchain**: If a blockchain's consensus is violated, it will be disconnected from the network until the Guardians resolve the issue.
- **Smart contract level data**: Via processes like the Governor, Guardians constantly monitor the circulating supply and token movements across all supported blockchains.
- **Guardian level activity**: The Guardian Network functions as an autonomous decentralized computing network, ensuring independent security measures across its validators.
## Asset Layer Protections
One key strength of the Wormhole ecosystem is the Guardians’ ability to validate and protect the integrity of assets across multiple blockchains.
To enforce the Wormhole Asset Layer’s core protections, the Global Accountant tracks the total circulating supply of all Wormhole assets across all chains, preventing any blockchain from bridging assets that could violate the supply invariant.
In addition to the Global Accountant, Guardians may only sign transfers that do not violate the requirements of the Governor. The [Governor](https://github.com/wormhole-foundation/wormhole/blob/main/whitepapers/0007_governor.md){target=\_blank} tracks inflows and outflows of all blockchains and delays suspicious transfers that may indicate an exploit.
## Open Source
Wormhole builds in the open and is always open source.
- **[Wormhole core repository](https://github.com/wormhole-foundation/wormhole){target=\_blank}**
- **[Wormhole Foundation GitHub organization](https://github.com/wormhole-foundation){target=\_blank}**
- **[Wormhole contract deployments](/docs/protocol/infrastructure/core-contracts/){target=\_blank}**
## Audits
Wormhole has been heavily audited, with _29 third-party audits completed_ and more started. Audits have been performed by the following firms:
- [Trail of Bits](https://www.trailofbits.com/){target=\_blank}
- [Neodyme](https://neodyme.io/en/){target=\_blank}
- [Kudelski](https://kudelskisecurity.com/){target=\_blank}
- [OtterSec](https://osec.io/){target=\_blank}
- [Certik](https://www.certik.com/){target=\_blank}
- [Hacken](https://hacken.io/){target=\_blank}
- [Zellic](https://www.zellic.io/){target=\_blank}
- [Coinspect](https://www.coinspect.com/){target=\_blank}
- [Halborn](https://www.halborn.com/){target=\_blank}
- [Cantina](https://cantina.xyz/welcome){target=\_blank}
All audits and final reports can be found in [security page of the GitHub Repo](https://github.com/wormhole-foundation/wormhole/blob/main/SECURITY.md#3rd-party-security-audits){target=\blank}.
## Bug Bounties
Wormhole has one of the largest bug bounty programs in software development and has repeatedly shown commitment to engaging with the white hat community.
Wormhole runs a bug bounty program through [Immunefi](https://immunefi.com/bug-bounty/wormhole/){target=\blank} program, with a top payout of **5 million dollars**.
If you are interested in contributing to Wormhole security, please look at this section for [Getting Started as a White Hat](https://github.com/wormhole-foundation/wormhole/blob/main/SECURITY.md#white-hat-hacking){target=\blank}, and follow the [Wormhole Contributor Guidelines](https://github.com/wormhole-foundation/wormhole/blob/main/CONTRIBUTING.md){target=\blank}.
For more information about submitting to the bug bounty programs, refer to the [Wormhole Immunefi page](https://immunefi.com/bug-bounty/wormhole/){target=\blank}.
## Learn More
The [SECURITY.md](https://github.com/wormhole-foundation/wormhole/blob/main/SECURITY.md){target=\blank} from the official repository has the latest security policies and updates.
--- END CONTENT ---
## Shared Concepts from reference
The following section contains reference material for Wormhole, including chain IDs, canonical contract addresses, finality levels, and other advanced specs. While it may not be required for all use cases, it provides a deeper layer for advanced development work.
---
## List of Shared Concept Pages:
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/core-contract-evm.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/core-contract-solana.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/relayer-contract.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/chain-ids.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/consistency-levels.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/contract-addresses.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/supported-networks.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/testnet-faucets.md [type: reference]
Doc-Page: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/wormhole-formatted-addresses.md [type: reference]
## Full content for shared concepts:
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/core-contract-evm.md
--- BEGIN CONTENT ---
---
title: Core Contract (EVM)
description: Reference for the Wormhole Core contract on EVM chains. Covers the proxy structure, components, state variables, functions, events, and errors.
categories: Reference
---
# Core Contract (EVM)
The [Wormhole Core Contract on EVM](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank} chains is a proxy-based contract responsible for receiving and verifying Wormhole messages (VAAs). It implements the messaging interface and delegates logic to upgradeable implementation contracts.
## Structure Overview
The Wormhole Core system consists of a proxy contract and a modular implementation constructed through layered inheritance.
```text
Wormhole.sol (Proxy)
└── Implementation.sol
└── Governance.sol
├── Getters.sol
├── GovernanceStructs.sol
├── Messages.sol
├── Setters.sol
└── Structs.sol
```
**Key Components:**
- **Wormhole.sol**: The upgradeable proxy contract that delegates all logic to `Implementation.sol`.
- **Implementation.sol**: The main logic contract, which handles message publication and initialization. Inherits from Governance.sol.
- **Governance.sol**: Core governance logic for processing upgrades, setting fees, and updating the Guardian set. Also responsible for verifying governance VAAs and performing privileged actions.
- **Getters.sol**: Exposes view functions to access internal contract state, such as current Guardian sets, fees, and contract configuration.
- **GovernanceStructs.sol**: Provides structures and helpers for processing governance-related VAAs.
- **Messages.sol**: Handles VAA parsing and verification.
- **Setters.sol**: Contains internal functions for mutating contract state.
- **Structs.sol**: Defines core data structures like GuardianSet and VM (VAA Message) used across multiple modules.
## State Variables
- **`provider` ++"Structs.Provider"++**: Holds metadata like `chainId`, `governanceChainId`, and `governanceContract`. This is a nested struct.
- **`guardianSets` ++"mapping(uint32 => GuardianSet)"++**: Mapping of all Guardian sets by index.
- **`guardianSetIndex` ++"uint32"++**: Index of the currently active Guardian set.
- **`guardianSetExpiry` ++"uint32"++**: How long a Guardian set remains valid after it's replaced (in seconds).
- **`sequences` ++"mapping(address => uint64)"++**: Tracks message sequences per emitter (used to enforce message ordering).
- **`consumedGovernanceActions` ++"mapping(bytes32 => bool)"++**: Used to prevent governance VAAs from being reused (replay protection).
- **`initializedImplementations` ++"mapping(address => bool)"++**: Tracks which implementation addresses have been initialized (for upgrade safety).
- **`messageFee` ++"uint256"++**: The amount (in native gas token) required to post a message. Set via governance.
- **`evmChainId` ++"uint256"++**: The actual EVM chain ID (e.g., 1 for Ethereum, 10 for Optimism). Used in fork recovery.
## Events
### LogMessagePublished
Emitted when a message is published via `publishMessage`. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
```solidity
event LogMessagePublished(
address indexed sender,
uint64 sequence,
uint32 nonce,
bytes payload,
uint8 consistencyLevel
)
```
??? interface "Parameters"
`sender` ++"address"++
Address that called `publishMessage`.
---
`sequence` ++"uint64"++
The sequence number of the message.
---
`nonce` ++"uint32"++
The provided nonce.
---
`payload` ++"bytes"++
The payload that was published.
---
`consistencyLevel` ++"uint8"++
Finality level requested.
### ContractUpgraded
Emitted when the Core Contract is upgraded to a new implementation via governance. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
```solidity
event ContractUpgraded(
address indexed oldContract,
address indexed newContract
)
```
??? interface "Parameters"
`oldContract` ++"address"++
The address of the previous implementation.
---
`newContract` ++"address"++
The address of the new implementation.
### GuardianSetAdded
Emitted when a new Guardian set is registered via governance. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
```solidity
event GuardianSetAdded(
uint32 indexed index
)
```
??? interface "Parameters"
`index` ++"uint32"++
Index of the newly added Guardian set.
### LogGuardianSetChanged
Emitted when the active Guardian set is changed. *(Defined in [State.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/State.sol){target=\_blank})*
```solidity
event LogGuardianSetChanged(
uint32 oldGuardianIndex,
uint32 newGuardianIndex
)
```
??? interface "Parameters"
`oldGuardianIndex` ++"uint32"++
The previous active Guardian set index.
---
`newGuardianIndex` ++"uint32"++
The new active Guardian set index.
## Functions
### publishMessage
Publishes a message to Wormhole's Guardian Network. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
```solidity
function publishMessage(
uint32 nonce,
bytes memory payload,
uint8 consistencyLevel
) public payable returns (uint64 sequence)
```
??? interface "Parameters"
`nonce` ++"uint32"++
Custom sequence identifier for the emitter.
---
`payload` ++"bytes"++
Arbitrary user data to be included in the message.
---
`consistencyLevel` ++"uint8"++
Finality requirement for Guardian attestation (e.g., safe or finalized).
??? interface "Returns"
`sequence` ++"uint64"++
Unique sequence number assigned to this message.
### getCurrentGuardianSetIndex
Returns the index of the currently active Guardian set. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
Each VAA includes the index of the Guardian set that signed it. This function allows contracts to retrieve the current index, ensuring the VAA is verified against the correct set.
```solidity
function getCurrentGuardianSetIndex() external view returns (uint32)
```
??? interface "Returns"
`index` ++"uint32"++
The index of the active Guardian set used to verify signatures.
### getGuardianSet
Retrieves metadata for a given Guardian set index. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function getGuardianSet(uint32 index) external view returns (address[] memory keys, uint32 expirationTime)
```
??? interface "Parameters"
`index` ++"uint32"++
Guardian set index to query.
??? interface "Returns"
`keys` ++"address[]"++
Public keys of the guardians in this set.
---
`expirationTime` ++"uint32"++
Timestamp after which the Guardian set is considered expired.
### getGuardianSetExpiry
Returns the expiration time of a specific Guardian set index. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function getGuardianSetExpiry(uint32 index) external view returns (uint32)
```
??? interface "Parameters"
`index` ++"uint32"++
The index of the Guardian set to query.
??? interface "Returns"
`expiry` ++"uint32"++
UNIX timestamp after which the set is no longer valid.
### messageFee
Returns the current fee (in native tokens) required to publish a message. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function messageFee() public view returns (uint256)
```
??? interface "Returns"
`fee` ++"uint256"++
Fee in Wei required to publish a message successfully. Must be sent as `msg.value`.
### nextSequence
Retrieves the next sequence number for a given emitter address. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function nextSequence(address emitter) external view returns (uint64)
```
??? interface "Parameters"
`emitter` ++"address"++
The address for which the next sequence will be issued.
??? interface "Returns"
`sequence` ++"uint64"++
The next sequence number for the specified emitter.
### parseAndVerifyVM
Verifies signatures and parses a signed VAA. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*
```solidity
function parseAndVerifyVM(bytes memory encodedVM)
external
view
returns (
VM memory vm,
bool valid,
string memory reason
)
```
??? interface "Parameters"
`encodedVM` ++"bytes"++
Serialized signed VAA from Guardians.
??? interface "Returns"
`vm` ++"VM memory"++
Full parsed VAA contents
---
`valid` ++"bool"++
Whether the VAA is valid according to the current Guardian set.
---
`reason` ++"string"++
Reason for invalidity if `valid` is false (invalid).
### verifyVM
Performs low-level VAA signature verification. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*
```solidity
function verifyVM(bytes memory encodedVM)
public view returns (bool isValid, string memory reason)
```
??? interface "Parameters"
`encodedVM` ++"bytes"++
Serialized signed VAA to verify.
??? interface "Returns"
`isValid` ++"bool"++
`true` if the signatures are valid and meet the quorum.
---
`reason` ++"string"++
Explanation for failure if `isValid` is `false`.
### verifySignatures
Used to verify individual Guardian signatures against a VAA digest. *(Defined in [Messages.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Messages.sol){target=\_blank})*
```solidity
function verifySignatures(
bytes32 hash,
Structs.Signature[] memory signatures,
GuardianSet memory guardianSet
) public view returns (bool)
```
??? interface "Parameters"
`hash` ++"bytes32"++
The message digest to verify.
---
`signatures` ++"Structs.Signature[]"++
An array of Guardian signatures.
---
`guardianSet` ++"GuardianSet memory"++
Guardian set to validate against.
??? interface "Returns"
`isValid` ++"bool"++
`true` if the required number of valid signatures is present.
### quorum
Returns the number of Guardian signatures required to reach quorum. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
```solidity
function quorum() public view returns (uint8)
```
??? interface "Returns"
`quorum` ++"uint8"++
Number of valid Guardian signatures required to reach consensus for VAA verification.
### chainId
Returns Wormhole chain ID used internally by the protocol. *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function chainId() public view returns (uint16)
```
??? interface "Returns"
`id` ++"uint16"++
Wormhole-specific chain identifier.
### evmChainId
Returns the EVM chain ID (i.e., value from `block.chainid`). *(Defined in [Getters.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Getters.sol){target=\_blank})*
```solidity
function evmChainId() public view returns (uint256)
```
??? interface "Returns"
`id` ++"uint256"++
Native EVM chain ID for the current network.
## Errors
### Invalid Fee
Reverts when the message fee (`msg.value`) sent is not equal to the required fee returned by `messageFee()`. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
### Unsupported
Reverts on any call to the fallback function. The contract does not support arbitrary calls. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
### The Wormhole Contract Does Not Accept Assets
Reverts when native tokens (ETH) are sent directly to the contract via the `receive()` function. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
### Already Initialized
Reverts when trying to call `initialize()` on an implementation that has already been initialized. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank}, via `initializer` modifier)*
### Unknown Chain ID
Reverts inside the `initialize()` function if the chain ID stored by the contract does not match any known Wormhole chain. *(Defined in [Implementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Implementation.sol){target=\_blank})*
### Invalid Fork
Reverts when attempting to perform a governance action intended only for forked chains on a non-forked chain. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Invalid Module
Reverts if the VAA’s module field doesn’t match the expected "Core" module. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Invalid Chain
Reverts if the VAA’s target chain doesn’t match the chain on which this contract is deployed. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### New Guardian Set is Empty
Reverts when trying to register a new Guardian set that has no keys. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Index Must Increase in Steps of 1
Reverts when the new Guardian set index is not exactly one greater than the current. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Not a Fork
Reverts when trying to recover chain ID on a non-forked chain. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Invalid EVM Chain
Reverts if the recovered chain ID doesn't match the current `block.chainid`. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Governance Action Already Consumed
Reverts when the same governance VAA is submitted more than once. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Wrong Governance Contract
Reverts when the governance VAA’s emitter address doesn't match the expected governance contract address. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Wrong Governance Chain
Reverts when the governance VAA’s emitter chain doesn't match the expected governance chain (Solana). *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
### Not Signed by Current Guardian Set
Reverts if the Guardian set index in the VAA doesn’t match the current Guardian set. *(Defined in [Governance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/ethereum/contracts/Governance.sol){target=\_blank})*
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/core-contract-solana.md
--- BEGIN CONTENT ---
---
title: Core Contract (Solana)
description: Reference for the Wormhole Core program on Solana. Covers architecture, PDA accounts, and instructions for posting, verifying, and processing VAAs.
categories: Reference
---
# Core Contract (Solana)
The [Wormhole Core Program on Solana](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/lib.rs){target=\_blank} is a native Solana program responsible for posting, verifying, and relaying Wormhole messages (VAAs). It implements core messaging functionality, Guardian set updates, and upgradeability.
## Structure Overview
The Wormhole Core program on Solana is implemented using modular Rust files. Logic is separated across instruction dispatch, account definitions, core types, and signature verification.
```text
lib.rs
├── instructions.rs
├── accounts.rs
├── api.rs
│ ├── post_message
│ ├── verify_signatures
│ ├── post_vaa
│ ├── upgrade_contract
│ └── upgrade_guardian_set
├── types.rs
└── vaa.rs
```
**Key Components:**
- **lib.rs**: Program entry point and instruction dispatcher. Registers all handlers and exposes the on-chain processor.
- **instructions.rs**: Defines the `WormholeInstruction` enum and maps it to individual instruction handlers.
- **accounts.rs**: Specifies the account constraints and validation logic for each instruction.
- **api.rs**: Contains the main logic for processing instructions such as message posting, VAA verification, upgrades, and governance actions.
- **types.rs**: Defines shared structs and enums used throughout the program, including configuration and `GuardianSet` formats.
- **vaa.rs**: Implements VAA parsing, hashing, and signature-related logic used to verify Wormhole messages.
- **error.rs** (not listed above): Defines custom error types used across the program for precise failure handling.
- **wasm.rs** (not listed above): Provides WebAssembly bindings for testing and external tooling; not used on-chain.
## State Accounts
Below are on-chain PDAs used to store persistent state for the core contract. All are derived using deterministic seeds with the program ID.
- **`bridge` ++"BridgeData"++**: Stores global config like the active Guardian set index, message fee, and Guardian set expiration time. (Derived at PDA seed `["Bridge"]`)
- **`guardianSets` ++"GuardianSetData"++**: Mapping of Guardian sets by index. Each Guardian set includes public key hashes and creation/expiration times. (Derived at PDA seed `["GuardianSet", index]`)
- **`sequences` ++"SequenceTracker"++**: Tracks the last sequence number used by each emitter, enforcing strict message ordering. (Derived at PDA seed `["Sequence", emitter]`)
- **`postedVAAs` ++"PostedVAAData"++**: Stores verified and finalized VAAs, preventing replay. (Derived at PDA seed `["PostedVAA", hash]`)
- **`claims` ++"ClaimData"++**: Tracks consumed governance VAAs to ensure replay protection. (Derived at PDA seed `["Claim", emitter, sequence]`)
- **`feeCollector` ++"FeeCollector"++**: Holds lamports collected via message fees, and can be drained via governance. (Derived at PDA seed `["fee_collector"]`)
## Instructions
### initialize
Initializes the Wormhole Core contract on Solana with a Guardian set and fee configuration. This should be called only once at deployment time. *(Defined in [api/initialize.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/initialize.rs){target=\_blank})*
```rust
initialize(
payer: Pubkey,
fee: u64,
guardian_set_expiration_time: u32,
initial_guardians: &[[u8; 20]]
)
```
??? interface "Accounts"
- **`Bridge`**: PDA to store global configuration.
- **`GuardianSet`**: PDA for Guardian set at index 0.
- **`FeeCollector`**: PDA to collect message posting fees.
- **`Payer`**: Funds account creation.
- **`Clock`, `Rent`, `SystemProgram`**: Solana system accounts.
??? interface "Parameters"
`fee` ++"u64"++
Fee in lamports required to post messages.
---
`guardian_set_expiration_time` ++"u32"++
Time in seconds after which the Guardian set expires.
---
`initial_guardians` ++"[[u8; 20]]"++
List of Guardian public key hashes (Ethereum-style addresses).
### post_message
Posts a Wormhole message to the Solana Core contract. *(Defined in [api/post_message.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/post_message.rs){target=\_blank})*
```rust
PostMessage {
nonce: u32,
payload: Vec,
consistency_level: u8
}
```
??? interface "Accounts"
- **`Bridge`**: PDA for global config.
- **`Message`**: PDA where the posted message will be stored.
- **`Emitter`**: The emitting account (must sign).
- **`Sequence`**: PDA tracking the emitter’s message sequence.
- **`Payer`**: Pays for account creation and fees.
- **`FeeCollector`**: PDA that collects message fees.
- **`Clock`, `Rent`, `SystemProgram`**: Solana system accounts.
??? interface "Parameters"
`nonce` ++"u32"++
Unique nonce to disambiguate messages with the same payload.
---
`payload` ++"Vec"++
The arbitrary message payload to be posted.
---
`consistency_level` ++"u8"++
Level of finality required before the message is processed.
`1` = Confirmed, `32` = Finalized.
### post_message_unreliable
Posts a Wormhole message without requiring reliable delivery. Used for lightweight publishing when finality isn't critical. *(Defined in [api/post_message.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/post_message.rs){target=\_blank})*
```rust
PostMessageUnreliable {
nonce: u32,
payload: Vec,
consistency_level: u8
}
```
??? interface "Accounts"
- **`Bridge`**: PDA for global config.
- **`Message`**: PDA where the posted message will be stored.
- **`Emitter`**: The emitting account (must sign).
- **`Sequence`**: PDA tracking the emitter’s message sequence.
- **`Payer`**: Pays for account creation and fees.
- **`FeeCollector`**: PDA that collects message fees.
- **`Clock`, `Rent`, `SystemProgram`**: Solana system accounts.
??? interface "Parameters"
`nonce` ++"u32"++
Unique nonce to disambiguate messages with the same payload.
---
`payload` ++"Vec"++
The arbitrary message payload to be posted.
---
`consistency_level` ++"u8"++
Level of finality required before the message is processed. `1` = Confirmed, `32` = Finalized.
### verify_signatures
Verifies Guardian signatures over a VAA body hash. This is the first step in VAA processing and is required before posting the VAA. *(Defined in [api/verify_signature.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/verify_signature.rs){target=\_blank})*
```rust
VerifySignatures {
signers: [i8; 19]
}
```
??? interface "Accounts"
- **`Payer`**: Pays for account creation and fees.
- **`GuardianSet`**: PDA holding the current Guardian set.
- **`SignatureSet`**: PDA that will store the verified signature data.
- **`InstructionsSysvar`**: Required to access prior instructions (e.g., secp256k1 sigverify).
- **`Rent`, `SystemProgram`**: Solana system accounts.
??? interface "Parameters"
`signers` ++"[i8; 19]"++
A mapping from Guardian index to its position in the instruction payload (or -1 if not present).
Used to correlate secp256k1 verify instructions with Guardian set entries.
### post_vaa
Finalizes a VAA after signature verification. This stores the message on-chain and marks it as consumed. *(Defined in [api/post_vaa.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/post_vaa.rs){target=\_blank})*
```rust
PostVAA {
version: u8,
guardian_set_index: u32,
timestamp: u32,
nonce: u32,
emitter_chain: u16,
emitter_address: [u8; 32],
sequence: u64,
consistency_level: u8,
payload: Vec
}
```
??? interface "Accounts"
- **`GuardianSet`**: PDA of the Guardian set used to verify the VAA.
- **`Bridge`**: Global Wormhole state.
- **`SignatureSet`**: Verified signature PDA (from verify_signatures).
- **`PostedVAA`**: PDA where the VAA will be stored.
- **`Payer`**: Funds the account creation.
- **`Clock`, `Rent`, `SystemProgram`**: Solana system accounts.
??? interface "Parameters"
`version` ++"u8"++
VAA protocol version.
---
`guardian_set_index` ++"u32"++
Index of the Guardian Set that signed this VAA.
---
`timestamp` ++"u32"++
The time the emitter submitted the message.
---
`nonce` ++"u32"++
Unique identifier for the message.
---
`emitter_chain` ++"u16"++
ID of the chain where the message originated.
---
`emitter_address` ++"[u8; 32]"++
Address of the contract or account that emitted the message.
---
`sequence` ++"u64"++
Monotonically increasing sequence number for the emitter.
---
`consistency_level` ++"u8"++
Required confirmation level before the message is accepted.
`1` = Confirmed, `32` = Finalized.
---
`payload` ++"Vec"++
Arbitrary data being transferred in the message.
### set_fees
Updates the message posting fee for the core bridge contract. *(Defined in [api/governance.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/governance.rs){target=\_blank})*
```rust
SetFees {}
```
This function is called via governance and requires a valid governance VAA. The VAA payload must contain the new fee value.
??? interface "Accounts"
- **`Payer`**: Funds transaction execution.
- **`Bridge`**: PDA storing global Wormhole state.
- **`Message`**: The PostedVAA account containing the governance message.
- **`Claim`**: PDA that ensures this governance message hasn't been processed already.
- **`SystemProgram`**: Required by Solana for creating/initializing accounts.
### transfer_fees
Transfers the accumulated message posting fees from the contract to a specified recipient. *(Defined in [api/governance.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/governance.rs){target=\_blank})*
```rust
TransferFees {}
```
This function is triggered via a governance VAA and transfers the fee balance from the `FeeCollector` to the recipient address specified in the VAA payload.
??? interface "Accounts"
- **`Payer`**: Funds transaction execution.
- **`Bridge`**: PDA storing global Wormhole state.
- **`Message`**: PostedVAA account containing the governance message.
- **`FeeCollector`**: PDA holding the accumulated fees.
- **`Recipient`**: The account that will receive the fees.
- **`Claim`**: PDA that ensures this governance message hasn't been processed already.
- **`Rent`, `SystemProgram`**: Standard Solana system accounts.
### upgrade_contract
Upgrades the deployed Wormhole program using a governance VAA. *(Defined in [api/governance.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/governance.rs){target=\_blank})*
```rust
UpgradeContract {}
```
This instruction allows authorized governance messages to trigger an upgrade of the on-chain Wormhole program logic to a new address.
??? interface "Accounts"
- **`Payer`**: Funds transaction execution.
- **`Bridge`**: PDA storing global Wormhole state.
- **`Message`**: PostedVAA account containing the governance message.
- **`Claim`**: PDA that ensures this governance message hasn't been processed already.
- **`UpgradeAuthority`**: PDA with authority to perform the upgrade (seeded with "upgrade").
- **`Spill`**: Account that receives remaining funds from the upgrade buffer.
- **`NewContract`**: Account holding the new program data.
- **`ProgramData`**: Metadata account for the upgradable program.
- **`Program`**: Current program to be upgraded.
- **`Rent`, `Clock`**: System accounts used during the upgrade process.
- **`BPFLoaderUpgradeable`**: Solana system program for upgrades.
- **`SystemProgram`**: Required by Solana for creating/initializing accounts.
### upgrade_guardian_set
Upgrades the current Guardian set using a governance VAA. *(Defined in [api/governance.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/api/governance.rs){target=\_blank})*
```rust
UpgradeGuardianSet {}
```
This instruction replaces the active Guardian set with a new one, allowing the Wormhole network to rotate its validator keys securely through governance.
??? interface "Accounts"
- **`Payer`**: Funds transaction execution.
- **`Bridge`**: PDA storing global Wormhole state.
- **`Message`**: PostedVAA account containing the governance message.
- **`Claim`**: PDA that ensures this governance message hasn't been processed already.
- **`GuardianSetOld`**: Current (active) Guardian set PDA.
- **`GuardianSetNew`**: PDA for the newly proposed Guardian set.
- **`SystemProgram`**: Standard Solana system accounts.
## Errors
### GuardianSetMismatch
The Guardian set index does not match the expected value. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InstructionAtWrongIndex
The instruction was found at the wrong index. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InsufficientFees
Insufficient fees were provided to post the message. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidFeeRecipient
The recipient address does not match the one specified in the governance VAA. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGovernanceAction
The action specified in the governance payload is invalid. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGovernanceChain
The governance VAA was not emitted by a valid governance chain. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGovernanceKey
The emitter address in the governance VAA is not the expected governance key. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGovernanceModule
The module string in the governance VAA header is invalid. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGovernanceWithdrawal
Fee withdrawal would cause the fee collector account to drop below rent-exempt balance. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidGuardianSetUpgrade
The Guardian set upgrade VAA is invalid (e.g., skipped index or mismatched current index). *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidHash
The hash computed from the VAA does not match the expected result. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidSecpInstruction
The SECP256k1 instruction used for signature verification is malformed. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### MathOverflow
An arithmetic overflow occurred during computation. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### PostVAAConsensusFailed
Not enough valid signatures were collected to achieve quorum. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### PostVAAGuardianSetExpired
The Guardian set used to verify the VAA has already expired. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### TooManyGuardians
The Guardian set exceeds the maximum allowed number of guardians. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### VAAAlreadyExecuted
The VAA has already been executed and cannot be processed again. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### VAAInvalid
The VAA is structurally invalid or fails to decode. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### InvalidPayloadLength
The payload length is incorrect or malformed. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
### EmitterChanged
The emitter address changed unexpectedly. *(Defined in [error.rs](https://github.com/wormhole-foundation/wormhole/blob/main/solana/bridge/program/src/error.rs){target=\_blank})*
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/messaging/reference/relayer-contract.md
--- BEGIN CONTENT ---
---
title: Relayer Contract
description: Reference for the Wormhole Relayer contract on EVM chains. Covers the proxy structure, components, state variables, functions, events, and errors.
categories: Reference
---
# Relayer Contract
The [Wormhole Relayer Contract on EVM](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayer.sol){target=\_blank} enables cross-chain message delivery with automatic execution on the destination chain. It publishes delivery instructions as Wormhole messages and defines the logic to process them via the `deliver` function. The contract supports optional value forwarding, gas refunds, message overrides, and integration with third-party delivery providers.
## Structure Overview
The Wormhole Relayer system on EVM is implemented as a modular, upgradeable contract suite, organized through layered inheritance and interfaces.
```text
IWormholeRelayer.sol (Interface)
└── WormholeRelayerBase.sol
├── WormholeRelayer.sol
├── CircleRelayer.sol
└── TypedUnits.sol
DeliveryProvider.sol (Standalone)
```
**Key Components:**
- **IWormholeRelayer.sol**: Defines the public interface for the Wormhole Relayer, including delivery functions and fee quoting.
- **WormholeRelayerBase.sol**: Base logic contract shared by both WormholeRelayer and CircleRelayer. Handles delivery processing, fee management, and VAA parsing.
- **WormholeRelayer.sol**: Main relayer implementation used with the Wormhole Messaging protocol. Inherits from `WormholeRelayerBase`.
- **CircleRelayer.sol**: Specialized implementation for Circle messages. Also extends `WormholeRelayerBase`, but is out of scope for this reference.
- **TypedUnits.sol**: Utility module for safe unit conversions, fee accounting, and delivery quote handling.
- **DeliveryProvider.sol**: Separate contract that sets and manages delivery pricing and supported chains. Queried by the relayer when calculating fees.
## State Variables
- **`chainId` ++"uint16"++**: Wormhole chain ID for the current network (e.g., 2 for Ethereum).
- **`wormhole` ++"IWormhole"++**: Address of the core Wormhole messaging contract used to verify VAAs.
- **`deliveryProvider` ++"address"++**: Address of the Delivery Provider contract responsible for quoting and setting delivery prices.
- **`rewardAddress` ++"address"++**: Address that receives excess fees collected from users.
- **`gasOverheads` ++"mapping(uint16 => GasOverhead)"++**: Per-chain gas overheads used to calculate delivery costs.
- **`supportedChains` ++"mapping(uint16 => bool)"++**: Tracks which destination chains are supported for message delivery.
- **`deliveries` ++"mapping(bytes32 => bool)"++**: Records completed deliveries (by VAA hash) to prevent replay.
- **`deliverySuccessBlock` ++"mapping(bytes32 => uint256)"++**: Stores the block number when a delivery succeeded (used for auditing).
- **`owner` ++"address"++**: Contract owner with permission to update system parameters (e.g., gas overheads).
- **`chainHash` ++"uint256"++**: EVM chain ID hash used for cross-checking delivery source chain.
- **`implementation` ++"address"++**: Address of the current logic contract (used in proxy pattern).
## Events
### SendEvent
Emitted when a send instruction is published and payment is handled. *(Defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
```solidity
event SendEvent(
uint64 indexed sequence,
LocalNative deliveryQuote,
LocalNative paymentForExtraReceiverValue
);
```
??? interface "Parameters"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction message.
---
`deliveryQuote` ++"LocalNative"++
Price charged by the delivery provider (in source chain currency units).
---
`paymentForExtraReceiverValue` ++"LocalNative"++
Extra amount (in source chain currency units) used to top up the receiver value on the target chain.
### Delivery
Emitted after a delivery attempt is executed by a delivery provider. *(Defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
```solidity
event Delivery(
address indexed recipientContract,
uint16 indexed sourceChain,
uint64 indexed sequence,
bytes32 deliveryVaaHash,
DeliveryStatus status,
Gas gasUsed,
RefundStatus refundStatus,
bytes additionalStatusInfo,
bytes overridesInfo
);
```
??? interface "Parameters"
`recipientContract` ++"address"++
Target contract that was called.
---
`sourceChain` ++"uint16"++
Wormhole chain ID where the delivery was requested.
---
`sequence` ++"uint64"++
Sequence number of the delivery VAA on the source chain.
---
`deliveryVaaHash` ++"bytes32"++
Hash of the delivery VAA.
---
`status` ++"DeliveryStatus"++
`SUCCESS` if the target call did not revert; `RECEIVER_FAILURE` if it reverted.
---
`gasUsed` ++"Gas"++
Gas consumed when calling the target contract.
---
`refundStatus` ++"RefundStatus"++
Result of the refund path (same-chain or cross-chain) or `NO_REFUND_REQUESTED`.
---
`additionalStatusInfo` ++"bytes"++
Empty on success; otherwise, truncated return data from the revert.
---
`overridesInfo` ++"bytes"++
Empty if not an override; otherwise, an encoded `DeliveryOverride`.
### ContractUpgraded (WormholeRelayer)
Emitted when the Wormhole Relayer contract is upgraded to a new implementation via governance. *(Defined in [WormholeRelayerGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerGovernance.sol){target=\_blank})*
```solidity
event ContractUpgraded(
address indexed oldContract,
address indexed newContract
);
```
??? interface "Parameters"
`oldContract` ++"address"++
Address of the previous implementation.
---
`newContract` ++"address"++
Address of the new implementation.
### ContractUpgraded (DeliveryProvider)
Emitted when the Delivery Provider contract is upgraded to a new implementation. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event ContractUpgraded(
address indexed oldContract,
address indexed newContract
);
```
??? interface "Parameters"
`oldContract` ++"address"++
Address of the previous implementation.
---
`newContract` ++"address"++
Address of the new implementation.
### ChainSupportUpdated
Emitted when Delivery Provider support for a target chain is changed. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event ChainSupportUpdated(
uint16 targetChain,
bool isSupported
);
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID whose support setting changed.
---
`isSupported` ++"bool"++
Whether deliveries to `targetChain` are supported.
### OwnershipTransfered
Emitted when Delivery Provider ownership is transferred. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event OwnershipTransfered(
address indexed oldOwner,
address indexed newOwner
);
```
??? interface "Parameters"
`oldOwner` ++"address"++
Previous owner.
---
`newOwner` ++"address"++
New owner.
### RewardAddressUpdated
Emitted when the Delivery Provider reward address is updated. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event RewardAddressUpdated(
address indexed newAddress
);
```
??? interface "Parameters"
`newAddress` ++"address"++
New reward address.
### TargetChainAddressUpdated
Emitted when the Delivery Provider's peer address for a target chain is updated. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event TargetChainAddressUpdated(
uint16 indexed targetChain,
bytes32 indexed newAddress
);
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID whose peer address changed.
---
`newAddress` ++"bytes32"++
New peer address in Wormhole bytes32 format.
### DeliverGasOverheadUpdated
Emitted when the configured gas overhead for deliveries is updated. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event DeliverGasOverheadUpdated(
Gas indexed oldGasOverhead,
Gas indexed newGasOverhead
);
```
??? interface "Parameters"
`oldGasOverhead` ++"Gas"++
Previous overhead value.
---
`newGasOverhead` ++"Gas"++
New overhead value.
### WormholeRelayerUpdated
Emitted when the Delivery Provider's associated Wormhole Relayer address is updated. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event WormholeRelayerUpdated(
address coreRelayer
);
```
??? interface "Parameters"
`coreRelayer` ++"address"++
New Wormhole Relayer contract address on this chain.
### AssetConversionBufferUpdated
Emitted when the Delivery Provider's asset conversion buffer is updated. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
```solidity
event AssetConversionBufferUpdated(
uint16 targetChain,
uint16 buffer,
uint16 bufferDenominator
);
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID whose buffer settings changed.
---
`buffer` ++"uint16"++
Buffer numerator.
---
`bufferDenominator` ++"uint16"++
Buffer denominator.
## Functions
### sendPayloadToEvm
Publishes an instruction for the default delivery provider to relay a payload to an EVM target. Must be called with `msg.value == quoteEVMDeliveryPrice(targetChain, receiverValue, gasLimit)`. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function sendPayloadToEvm(
uint16 targetChain,
address targetAddress,
bytes memory payload,
TargetNative receiverValue,
Gas gasLimit
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`targetAddress` ++"address"++
Contract on the destination chain (must implement `IWormholeReceiver`).
---
`payload` ++"bytes"++
Bytes delivered to `targetAddress`.
---
`receiverValue` ++"TargetNative"++
Value (destination chain Wei) to forward to `targetAddress`.
---
`gasLimit` ++"Gas"++
Gas limit for calling `targetAddress`.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction.
### sendPayloadToEvm (with refund)
Same as above, but sends any refund to refundAddress on refundChain. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function sendPayloadToEvm(
uint16 targetChain,
address targetAddress,
bytes memory payload,
TargetNative receiverValue,
Gas gasLimit,
uint16 refundChain,
address refundAddress
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`targetAddress` ++"address"++
Contract on the destination chain (must implement `IWormholeReceiver`).
---
`payload` ++"bytes"++
Bytes delivered to `targetAddress`.
---
`receiverValue` ++"TargetNative"++
Value (destination chain Wei) to forward to `targetAddress`.
---
`gasLimit` ++"Gas"++
Gas limit for calling `targetAddress`.
---
`refundChain` ++"uint16"++
Wormhole chain ID where refunds should be sent.
---
`refundAddress` ++"address"++
Address on `refundChain` to receive refunds.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction.
### sendVaasToEvm (with refund)
Publishes an instruction (default delivery provider) to relay a payload and additional VAAs. Refunds go to `refundAddress` on `refundChain`. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function sendVaasToEvm(
uint16 targetChain,
address targetAddress,
bytes memory payload,
TargetNative receiverValue,
Gas gasLimit,
VaaKey[] memory vaaKeys,
uint16 refundChain,
address refundAddress
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`targetAddress` ++"address"++
Contract on the destination chain (must implement `IWormholeReceiver`).
---
`payload` ++"bytes"++
Bytes delivered to `targetAddress`.
---
`receiverValue` ++"TargetNative"++
Value (destination chain Wei) to forward to `targetAddress`.
---
`gasLimit` ++"Gas"++
Gas limit for calling `targetAddress`.
---
`vaaKeys` ++"VaaKey[]"++
Extra Wormhole messages (VAAs) to deliver along with `payload`.
---
`refundChain` ++"uint16"++
Wormhole chain ID where any refund will be sent.
---
`refundAddress` ++"address"++
Address on `refundChain` that receives any refund.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction.
### sendToEvm (MessageKeys)
Publishes an instruction using a specific delivery provider, optionally attaching extra receiver value funded on the source chain and arbitrary MessageKeys (e.g., VAAs or other supported keys). *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function sendToEvm(
uint16 targetChain,
address targetAddress,
bytes memory payload,
TargetNative receiverValue,
LocalNative paymentForExtraReceiverValue,
Gas gasLimit,
uint16 refundChain,
address refundAddress,
address deliveryProviderAddress,
MessageKey[] memory messageKeys,
uint8 consistencyLevel
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`targetAddress` ++"address"++
Contract on the destination chain (must implement `IWormholeReceiver`).
---
`payload` ++"bytes"++
Bytes delivered to `targetAddress`.
---
`receiverValue` ++"TargetNative"++
Value (destination chain Wei) to forward to `targetAddress`.
---
`paymentForExtraReceiverValue` ++"LocalNative"++
Extra source chain amount. The delivery provider converts this to destination native and adds it to `receiverValue`.
---
`gasLimit` ++"Gas"++
Gas limit for calling `targetAddress` on the destination chain.
---
`refundChain` ++"uint16"++
Wormhole chain ID where any refund will be sent.
---
`refundAddress` ++"address"++
Address on `refundChain` that receives any refund.
---
`deliveryProviderAddress` ++"address"++
Chosen delivery provider (must implement `IDeliveryProvider`).
---
`messageKeys` ++"MessageKey[]"++
External messages to deliver (e.g., VAAs). Each key’s `keyType` **must** be supported by the delivery provider; otherwise the call reverts.
---
`consistencyLevel` ++"uint8"++
Wormhole publishing consistency (e.g., instant vs. finalized) used when emitting the delivery instruction.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction.
### send (MessageKeys, generic)
Generic chain-agnostic form (addresses are Wormhole-formatted bytes32, and execution params are encoded). *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function send(
uint16 targetChain,
bytes32 targetAddress,
bytes memory payload,
TargetNative receiverValue,
LocalNative paymentForExtraReceiverValue,
bytes memory encodedExecutionParameters,
uint16 refundChain,
bytes32 refundAddress,
address deliveryProviderAddress,
MessageKey[] memory messageKeys,
uint8 consistencyLevel
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`targetAddress` ++"bytes32"++
Wormhole-formatted 32-byte address of the destination contract.
---
`payload` ++"bytes"++
Bytes delivered to `targetAddress`.
---
`receiverValue` ++"TargetNative"++
Amount of destination chain native (e.g., Wei) forwarded to `targetAddress`.
---
`paymentForExtraReceiverValue` ++"LocalNative"++
Extra source chain native to be converted by the delivery provider and added to `receiverValue`.
---
`encodedExecutionParameters` ++"bytes"++
Versioned execution params for the target chain (e.g., for EVM use `encodeEvmExecutionParamsV1(EvmExecutionParamsV1(gasLimit))`).
---
`refundChain` ++"uint16"++
Wormhole chain ID where any refund will be sent.
---
`refundAddress` ++"bytes32"++
Wormhole-formatted address on `refundChain` that receives any refund.
---
`deliveryProviderAddress` ++"address"++
Chosen delivery provider (must implement `IDeliveryProvider`).
---
`messageKeys` ++"MessageKey[]"++
External messages to deliver (e.g., VAAs). Each key’s `keyType` **must** be supported by the delivery provider.
---
`consistencyLevel` ++"uint8"++
Wormhole publishing consistency used when emitting the delivery instruction.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the published delivery instruction.
### resendToEvm
Requests a previously published delivery instruction to be redelivered (EVM convenience). *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function resendToEvm(
VaaKey memory deliveryVaaKey,
uint16 targetChain,
TargetNative newReceiverValue,
Gas newGasLimit,
address newDeliveryProviderAddress
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`deliveryVaaKey` ++"VaaKey"++
Identifies the original delivery instruction VAA.
---
`targetChain` ++"uint16"++
Wormhole chain ID where the message should be redelivered.
---
`newReceiverValue` ++"TargetNative"++
Updated value sent to the target contract.
---
`newGasLimit` ++"Gas"++
Updated gas limit for the target call.
---
`newDeliveryProviderAddress` ++"address"++
Delivery provider to use for the redelivery.
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the redelivery instruction.
### resend (generic)
Generic redelivery (chain-agnostic execution params). *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function resend(
VaaKey memory deliveryVaaKey,
uint16 targetChain,
TargetNative newReceiverValue,
bytes memory newEncodedExecutionParameters,
address newDeliveryProviderAddress
) external payable returns (uint64 sequence)
```
??? interface "Parameters"
`deliveryVaaKey` ++"VaaKey"++
Identifies the original delivery instruction VAA.
---
`targetChain` ++"uint16"++
Wormhole chain ID where the message should be redelivered.
---
`newReceiverValue` ++"TargetNative"++
Updated value to forward to the target contract on the destination chain.
---
`newEncodedExecutionParameters` ++"bytes"++
Versioned, chain-specific execution params for the redelivery (e.g., for EVM use `encodeEvmExecutionParamsV1(EvmExecutionParamsV1(gasLimit))`).
---
`newDeliveryProviderAddress` ++"address"++
Delivery provider to use for the redelivery (must implement `IDeliveryProvider`).
??? interface "Returns"
`sequence` ++"uint64"++
Sequence number of the redelivery instruction.
### quoteEVMDeliveryPrice (default provider)
Returns the price and refund-per-gas info for an EVM delivery using the default provider. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function quoteEVMDeliveryPrice(
uint16 targetChain,
TargetNative receiverValue,
Gas gasLimit
) external view returns (LocalNative nativePriceQuote, GasPrice targetChainRefundPerGasUnused)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`receiverValue` ++"TargetNative"++
Amount of destination chain Wei that will be forwarded to the target contract.
---
`gasLimit` ++"Gas"++
Gas limit that will be used to call the target contract.
??? interface "Returns"
`nativePriceQuote` ++"LocalNative"++
Source chain price to request the delivery.
---
`targetChainRefundPerGasUnused` ++"GasPrice"++
Refund rate per unused gas on target chain.
### quoteEVMDeliveryPrice (explicit provider)
Same as above, but quotes using a given provider. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function quoteEVMDeliveryPrice(
uint16 targetChain,
TargetNative receiverValue,
Gas gasLimit,
address deliveryProviderAddress
) external view returns (LocalNative nativePriceQuote, GasPrice targetChainRefundPerGasUnused)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`receiverValue` ++"TargetNative"++
Amount of destination chain Wei to forward to the target contract.
---
`gasLimit` ++"Gas"++
Gas limit to call the target contract with.
---
`deliveryProviderAddress` ++"address"++
Address of the chosen provider (implements `IDeliveryProvider`).
??? interface "Returns"
`nativePriceQuote` ++"LocalNative"++
Source chain price to request this delivery.
---
`targetChainRefundPerGasUnused` ++"GasPrice"++
Refund rate per unit of unused gas on the destination chain.
### quoteDeliveryPrice (generic)
Generic quote (versioned execution params), returning price and provider's encoded execution info. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function quoteDeliveryPrice(
uint16 targetChain,
TargetNative receiverValue,
bytes memory encodedExecutionParameters,
address deliveryProviderAddress
) external view returns (LocalNative nativePriceQuote, bytes memory encodedExecutionInfo)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`receiverValue` ++"TargetNative"++
Amount of destination chain Wei to forward to the target contract.
---
`encodedExecutionParameters` ++"bytes"++
Versioned execution parameters (e.g., for `EVM_V1`, encodes the gas limit).
---
`deliveryProviderAddress` ++"address"++
Address of the chosen provider (implements `IDeliveryProvider`).
??? interface "Returns"
`nativePriceQuote` ++"LocalNative"++
Source chain price to request this delivery.
---
`encodedExecutionInfo` ++"bytes"++
Provider's encoded execution info (e.g., for `EVM_V1`, includes gas limit and refund-per-gas).
### quoteNativeForChain
Converts a source chain amount into extra value that will be delivered on the target chain. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function quoteNativeForChain(
uint16 targetChain,
LocalNative currentChainAmount,
address deliveryProviderAddress
) external view returns (TargetNative targetChainAmount)
```
??? interface "Parameters"
`targetChain` ++"uint16"++
Wormhole chain ID of the destination chain.
---
`currentChainAmount` ++"LocalNative"++
Amount paid on the source chain to fund extra receiver value.
---
`deliveryProviderAddress` ++"address"++
Address of the chosen provider (implements `IDeliveryProvider`).
??? interface "Returns"
`targetChainAmount` ++"TargetNative"++
Extra destination chain Wei that will be added to the call's value.
### getDefaultDeliveryProvider
Returns the current default delivery provider address. *(Defined in [WormholeRelayerSend.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerSend.sol){target=\_blank})*
```solidity
function getDefaultDeliveryProvider() external view returns (address deliveryProvider)
```
??? interface "Returns"
`deliveryProvider` ++"address"++
Address of the default `IDeliveryProvider` on this chain.
### deliver
Called by a delivery provider to execute a delivery on the target chain. *(Defined in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank})*
```solidity
function deliver(
bytes[] memory encodedVMs,
bytes memory encodedDeliveryVAA,
address payable relayerRefundAddress,
bytes memory deliveryOverrides
) external payable
```
??? interface "Parameters"
`encodedVMs` ++"bytes[]"+
Signed Wormhole messages to relay.
---
`encodedDeliveryVAA` ++"bytes"++
Signed WormholeRelayer instruction VAA.
---
`relayerRefundAddress` ++"address payable"++
Address to receive any relayer refund.
---
`deliveryOverrides` ++"bytes"++
Optional encoded overrides (or empty).
### deliveryAttempted
Checks whether a delivery attempt has been made for a given hash. *(Defined in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank})*
```solidity
function deliveryAttempted(bytes32 deliveryHash) external view returns (bool attempted)
```
??? interface "Parameters"
`deliveryHash` ++"bytes32"++
Hash of the delivery VAA.
??? interface "Returns"
`attempted` ++"bool"++
`true` if a success or failure block was recorded for this hash.
### deliverySuccessBlock
Block number when a delivery was successfully executed. *(Defined in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank})*
```solidity
function deliverySuccessBlock(bytes32 deliveryHash) external view returns (uint256 blockNumber)
```
??? interface "Parameters"
`deliveryHash` ++"bytes32"++
Hash of the delivery VAA.
??? interface "Returns"
`blockNumber` ++"uint256"++
Block number where the delivery was marked successful (0 if never successful).
### deliveryFailureBlock
Block number of the latest failed delivery attempt. *(Defined in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank})*
```solidity
function deliveryFailureBlock(bytes32 deliveryHash) external view returns (uint256 blockNumber)
```
??? interface "Parameters"
`deliveryHash` ++"bytes32"++
Hash of the delivery VAA.
??? interface "Returns"
`blockNumber` ++"uint256"++
Block number of the most recent failed attempt (0 if none).
### getRegisteredWormholeRelayerContract
Returns the registered Wormhole Relayer contract address (wormhole format) for a given chain ID. *(Defined in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank})*
```solidity
function getRegisteredWormholeRelayerContract(uint16 chainId) external view returns (bytes32)
```
??? interface "Parameters"
`chainId` ++"uint16"++
Wormhole chain ID.
??? interface "Returns"
`address` ++"bytes32"++
Wormhole-formatted address of the relayer contract registered for `chainId` (zero if none).
### registerWormholeRelayerContract
Registers a Wormhole Relayer contract deployed on another chain (governance VM required). *(Defined in [WormholeRelayerGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerGovernance.sol){target=\_blank})*
```solidity
function registerWormholeRelayerContract(bytes memory encodedVm) external
```
??? interface "Parameters"
`encodedVm` ++"bytes"++
Signed governance VM that encodes the `foreignChainId` and `foreignContractAddress`.
### setDefaultDeliveryProvider
Sets the default delivery provider via a governance VM. *(Defined in [WormholeRelayerGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerGovernance.sol){target=\_blank})*
```solidity
function setDefaultDeliveryProvider(bytes memory encodedVm) external
```
??? interface "Parameters"
`encodedVm` ++"bytes"++
Signed governance VM that encodes the new provider address.
### submitContractUpgrade
Upgrades the Wormhole Relayer contract to a new implementation (governance VM required). *(Defined in [WormholeRelayerGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerGovernance.sol){target=\_blank})*
```solidity
function submitContractUpgrade(bytes memory encodedVm) external
```
??? interface "Parameters"
`encodedVm` ++"bytes"++
Signed governance VM that encodes the new implementation address.
## Errors
### InvalidDeliveryVaa
Thrown when the delivery VAA fails `parseAndVerifyVM`. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### InvalidEmitter
Emitted when the VAA emitter is not the registered Wormhole Relayer for the source chain. *(Used in WormholeRelayerDelivery.sol, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### InsufficientRelayerFunds
Reverts if `msg.value` is less than the required execution + refund budget on the target chain. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### TargetChainIsNotThisChain
Reverts when the instruction's `targetChain` does not match the current chain. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### MessageKeysLengthDoesNotMatchMessagesLength
Reverts when the provided message keys do not match the number of delivered messages. (Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}), defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})
### VaaKeysDoNotMatchVaas
Reverts when described VAAs don't match the actual VAAs delivered. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### InvalidOverrideGasLimit
Reverts if a redelivery override sets a gas limit lower than the original. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### InvalidOverrideReceiverValue
Reverts if a redelivery override sets a receiver value lower than the original. *(Used in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### InvalidMsgValue
Reverts when msg.value does not equal `wormholeMessageFee` + `deliveryQuote` + `paymentForExtraReceiverValue`. *(Used in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### ReentrantDelivery
Reverts on re-entrant calls to relayer entrypoints guarded by `nonReentrant`. *(Used in [WormholeRelayerBase.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerBase.sol){target=\_blank}, defined in [IWormholeRelayerTyped.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/interfaces/relayer/IWormholeRelayerTyped.sol){target=\_blank})*
### CallerNotApproved(address msgSender)
Custom error declared for access checks. *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### PriceIsZero(uint16 chain)
Reverts if a required price value for a chain is zero during quoting/conversion. *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### Overflow(uint256 value, uint256 max)
Reverts when an internal quote exceeds a type's allowed maximum (e.g., gas overhead/price bounds). *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### MaxRefundGreaterThanGasLimitCost(uint256 maxRefund, uint256 gasLimitCost)
Declared to guard refund limits vs. gas limit cost. *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### MaxRefundGreaterThanGasLimitCostOnSourceChain(uint256 maxRefund, uint256 gasLimitCost)
Declared to guard source chain refund limits vs. gas limit cost. *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### ExceedsMaximumBudget(uint16 targetChain, uint256 exceedingValue, uint256 maximumBudget)
Reverts when required target-chain Wei (receiver value + gas) exceeds that chain's configured maximum budget. *(Defined in [DeliveryProvider.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProvider.sol){target=\_blank})*
### ChainIdIsZero()
Reverts if an update is attempted with `chainId = 0`. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### GasPriceIsZero()
Reverts if a price update sets gas price to zero. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### NativeCurrencyPriceIsZero()
Reverts if a price update sets native currency price to zero. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### FailedToInitializeImplementation(string reason)
Reverts if the implementation's `initialize()` delegatecall fails during upgrade/setup. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank} and [DeliveryProviderSetup.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderSetup.sol){target=\_blank})*
### WrongChainId()
Reverts when an operation is invoked with a chainId that doesn't match the contract's configured chain. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### AddressIsZero()
Reverts if a zero address is provided where a nonzero address is required (e.g., ownership handoff). *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### CallerMustBePendingOwner()
Reverts if `confirmOwnershipTransferRequest` is called by an address other than `pendingOwner`. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### CallerMustBeOwner()
Reverts on functions guarded by `onlyOwner` when `msg.sender` is not the owner. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### CallerMustBeOwnerOrPricingWallet()
Reverts on functions guarded by `onlyOwnerOrPricingWallet` when caller is neither. *(Defined in [DeliveryProviderGovernance.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderGovernance.sol){target=\_blank})*
### ImplementationAlreadyInitialized()
Reverts if `initialize()` is called on an implementation that was already initialized. *(Defined in [DeliveryProviderImplementation.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderImplementation.sol){target=\_blank})*
### ImplementationAddressIsZero()
Reverts if `setup()` is called with a zero implementation address. *(Defined in [DeliveryProviderSetup.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/deliveryProvider/DeliveryProviderSetup.sol){target=\_blank})*
### UnexpectedExecutionInfoVersion
Reverts when the `executionInfoVersion` in the delivery VAA does not match the expected version. *(Defined in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank})*
### VersionMismatchOverride
Reverts when the override's `executionInfoVersion` does not match the original delivery's version. *(Defined in [WormholeRelayerDelivery.sol](https://github.com/wormhole-foundation/wormhole/blob/main/relayer/ethereum/contracts/relayer/wormholeRelayer/WormholeRelayerDelivery.sol){target=\_blank})*
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/chain-ids.md
--- BEGIN CONTENT ---
---
title: Chain IDs
description: This page documents the Wormhole-specific chain IDs for each chain and contrasts them to the more commonly referenced EVM chain IDs originating in EIP-155.
categories: Reference
---
# Chain IDs
The following table documents the chain IDs used by Wormhole and places them alongside the more commonly referenced [EVM Chain IDs](https://chainlist.org/){target=\_blank}.
!!! note
Please note, Wormhole chain IDs are different than the more commonly referenced [EVM chain IDs](https://chainlist.org/){target=\_blank}, specified in the Mainnet and Testnet ID columns.
!!!warning
Wormhole Contributors recommend that all connected chains implement robust security practices including (but not exclusively): open sourcing code and running public bug bounty programs, undergoing security audits and publishing those reports, using version control with adequate access controls and mandatory code review, and high unit and integration test coverage where the results of those tests are available publicly. Connected chains that can't verifiably prove that they've implemented a high percentage of these practices may be noted below with the :warning: symbol.
Wormhole integrators are encouraged to understand the security assumptions of any chain before trusting messages from it. See the recommended security practices for chains in [Wormhole's security program](https://github.com/wormhole-foundation/wormhole/blob/main/SECURITY.md#chain-integrators){target=\_blank}.
=== "Mainnet"
| Ethereum | 2 | 1 |
| Solana | 1 | Mainnet Beta-5eykt4UsFv8P8NJdTREpY1vzqKqZKvdpKuc147dw2N9d |
| Algorand | 8 | mainnet-v1.0 |
| Aptos | 22 | 1 |
| Arbitrum | 23 | Arbitrum One-42161 |
| Avalanche | 6 | C-Chain-43114 |
| Base | 30 | Base-8453 |
| Berachain | 39 | |
| BNB Smart Chain | 4 | 56 |
| Celestia | 4004 | celestia |
| Celo | 14 | 42220 |
| Converge | 53 | |
| Cosmos Hub | 4000 | cosmoshub-4 |
| Dymension | 4007 | dymension_1100-1 |
| Evmos | 4001 | evmos_9001-2 |
| Fantom | 10 | 250 |
| Fogo | 51 | |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 47 | |
| Injective | 19 | injective-1 |
| Ink | 46 | |
| Kaia | 13 | 8217 |
| Kujira | 4002 | kaiyo-1 |
| Linea | 38 | 59144 |
| Mantle | 35 | 5000 |
| Mezo | 50 | |
| Monad | 48 | |
| Moonbeam | 16 | 1284 |
| NEAR | 15 | mainnet |
| Neutron | 4003 | neutron-1 |
| Noble | 4009 | noble-1 |
| Optimism | 24 | 10 |
| Osmosis | 20 | osmosis-1 |
| Plume | 55 | 98866 |
| Polygon | 5 | 137 |
| Provenance | 4008 | pio-mainnet-1 |
| Pythnet | 26 | |
| Scroll | 34 | 534352 |
| SEDA | 4006 | |
| Sei | 32 | pacific-1 |
| Seievm | 40 | |
| Sonic | 52 | 146 |
| Stargaze | 4005 | stargaze-1 |
| Sui | 21 | 35834a8a |
| Unichain | 44 | |
| World Chain | 45 | 480 |
| X Layer | 37 | 196 |
| XRPL-EVM | 57 | 1440000 |
=== "Testnet"
| Ethereum Holesky | 10006 | Holesky-17000 |
| Ethereum Sepolia | 10002 | Sepolia-11155111 |
| Solana | 1 | Devnet-EtWTRABZaYq6iMfeYKouRu166VU2xqa1wcaWoxPkrZBG |
| Algorand | 8 | testnet-v1.0 |
| Aptos | 22 | 2 |
| Arbitrum Sepolia | 10003 | Sepolia-421614 |
| Avalanche | 6 | Fuji-43113 |
| Base Sepolia | 10004 | Base Sepolia-84532 |
| Berachain | 39 | 80084 |
| BNB Smart Chain | 4 | 97 |
| Celestia | 4004 | mocha-4 |
| Celo | 14 | Alfajores-44787 |
| Converge | 53 | 52085145 |
| Cosmos Hub | 4000 | theta-testnet-001 |
| Dymension | 4007 | |
| Evmos | 4001 | evmos_9000-4 |
| Fantom | 10 | 4002 |
| Fogo | 51 | 9GGSFo95raqzZxWqKM5tGYvJp5iv4Dm565S4r8h5PEu9 |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 47 | 998 |
| Injective | 19 | injective-888 |
| Ink | 46 | 763373 |
| Kaia | 13 | Kairos-1001 |
| Kujira | 4002 | harpoon-4 |
| Linea | 38 | 59141 |
| Mantle | 35 | Sepolia-5003 |
| Mezo | 50 | 31611 |
| Monad | 48 | 10143 |
| Moonbeam | 16 | Moonbase-Alphanet-1287 |
| NEAR | 15 | testnet |
| Neutron | 4003 | pion-1 |
| Noble | 4009 | grand-1 |
| Optimism Sepolia | 10005 | Optimism Sepolia-11155420 |
| Osmosis | 20 | osmo-test-5 |
| Plume | 55 | 98867 |
| Polygon Amoy | 10007 | Amoy-80002 |
| Provenance | 4008 | |
| Pythnet | 26 | |
| Scroll | 34 | Sepolia-534351 |
| SEDA | 4006 | seda-1-testnet |
| Sei | 32 | atlantic-2 |
| Seievm | 40 | |
| Sonic | 52 | 57054 |
| Stargaze | 4005 | |
| Sui | 21 | 4c78adac |
| Unichain | 44 | Unichain Sepolia-1301 |
| World Chain | 45 | 4801 |
| X Layer | 37 | 195 |
| XRPL-EVM | 57 | 1449000 |
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/consistency-levels.md
--- BEGIN CONTENT ---
---
title: Wormhole Finality | Consistency Levels
description: This page documents how long to wait for finality before signing, based on each chain’s consistency (finality) level and consensus mechanism.
categories: Reference
---
# Wormhole Finality
The following table documents each chain's `consistencyLevel` values (i.e., finality reached before signing). The consistency level defines how long the Guardians should wait before signing a VAA. The finalization time depends on the specific chain's consensus mechanism. The consistency level is a `u8`, so any single byte may be used. However, a small subset has particular meanings. If the `consistencyLevel` isn't one of those specific values, the `Otherwise` column describes how it's interpreted.
| Ethereum | 200 | 201 | | finalized | ~ 19min | Details |
| Solana | | 0 | 1 | | ~ 14s | Details |
| Algorand | | | 0 | | ~ 4s | Details |
| Aptos | | | 0 | | ~ 4s | Details |
| Arbitrum | 200 | 201 | | finalized | ~ 18min | Details |
| Avalanche | 200 | | | finalized | ~ 2s | Details |
| Base | 200 | 201 | | finalized | ~ 18min | |
| Berachain | 200 | | | finalized | ~ 4s | |
| BNB Smart Chain | 200 | 201 | | finalized | ~ 48s | Details |
| Celestia | | | 0 | | ~ 5s | |
| Celo | 200 | | | finalized | ~ 10s | |
| Converge | | | 0 | | ~ 7min | |
| Cosmos Hub | | | 0 | | ~ 5s | |
| Dymension | | | 0 | | ~ 5s | |
| Evmos | | | 0 | | ~ 2s | |
| Fantom | 200 | | | finalized | ~ 5s | |
| Fogo | | | 0 | | ~ 14s | |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | | | 0 | | ~ 2s | |
| Injective | | | 0 | | ~ 3s | |
| Ink | | | 0 | | ~ 9min | |
| Kaia | 200 | | | finalized | ~ 1s | |
| Kujira | | | 0 | | ~ 3s | |
| Mantle | 200 | 201 | | finalized | ~ 18min | |
| Mezo | | | 0 | | ~ 8s | |
| Monad | | | 0 | | ~ 2s | |
| Moonbeam | 200 | 201 | | finalized | ~ 24s | Details |
| NEAR | | | 0 | | ~ 2s | Details |
| Neutron | | | 0 | | ~ 5s | |
| Optimism | 200 | 201 | | finalized | ~ 18min | |
| Osmosis | | | 0 | | ~ 6s | |
| Plume | | | 0 | | ~ 18min | |
| Polygon | 200 | | | finalized | ~ 66s | Details |
| Scroll | 200 | | | finalized | ~ 16min | |
| Sei | | | 0 | | ~ 1s | |
| Seievm | | | 0 | | ~ 1s | |
| Sonic | | | 0 | | ~ 1s | |
| Stargaze | | | 0 | | ~ 5s | |
| Sui | | | 0 | | ~ 3s | Details |
| Unichain | 200 | 201 | | finalized | ~ 18min | |
| World Chain | | | 0 | | ~ 18min | |
| X Layer | 200 | 201 | | finalized | ~ 16min | |
| XRPL-EVM | | | 0 | | ~ 10s | |
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/contract-addresses.md
--- BEGIN CONTENT ---
---
title: Contract Addresses
description: This page documents the deployed contract addresses of the Wormhole contracts on each chain, including Core Contracts, TokenBridge, and more.
categories: Reference
---
# Contract Addresses
## Core Contracts
=== "Mainnet"
| Ethereum | 0x98f3c9e6E3fAce36bAAd05FE09d375Ef1464288B |
| Solana | worm2ZoG2kUd4vFXhvjh93UUH596ayRfgQ2MgjNMTth |
| Algorand | 842125965 |
| Aptos | 0x5bc11445584a763c1fa7ed39081f1b920954da14e04b32440cba863d03e19625 |
| Arbitrum | 0xa5f208e072434bC67592E4C49C1B991BA79BCA46 |
| Avalanche | 0x54a8e5f9c4CbA08F9943965859F6c34eAF03E26c |
| Base | 0xbebdb6C8ddC678FfA9f8748f85C815C556Dd8ac6 |
| Berachain | 0xCa1D5a146B03f6303baF59e5AD5615ae0b9d146D |
| BNB Smart Chain | 0x98f3c9e6E3fAce36bAAd05FE09d375Ef1464288B |
| Celo | 0xa321448d90d4e5b0A732867c18eA198e75CAC48E |
| Fantom | 0x126783A6Cb203a3E35344528B26ca3a0489a1485 |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 0x7C0faFc4384551f063e05aee704ab943b8B53aB3 |
| Injective | inj17p9rzwnnfxcjp32un9ug7yhhzgtkhvl9l2q74d |
| Ink | 0xCa1D5a146B03f6303baF59e5AD5615ae0b9d146D |
| Kaia | 0x0C21603c4f3a6387e241c0091A7EA39E43E90bb7 |
| Mantle | 0xbebdb6C8ddC678FfA9f8748f85C815C556Dd8ac6 |
| Mezo | 0xaBf89de706B583424328B54dD05a8fC986750Da8 |
| Moonbeam | 0xC8e2b0cD52Cf01b0Ce87d389Daa3d414d4cE29f3 |
| NEAR | contract.wormhole_crypto.near |
| Neutron | neutron16rerygcpahqcxx5t8vjla46ym8ccn7xz7rtc6ju5ujcd36cmc7zs9zrunh |
| Optimism | 0xEe91C335eab126dF5fDB3797EA9d6aD93aeC9722 |
| Plume | 0xaBf89de706B583424328B54dD05a8fC986750Da8 |
| Polygon | 0x7A4B5a56256163F07b2C80A7cA55aBE66c4ec4d7 |
| Pythnet | H3fxXJ86ADW2PNuDDmZJg6mzTtPxkYCpNuQUTgmJ7AjU |
| Scroll | 0xbebdb6C8ddC678FfA9f8748f85C815C556Dd8ac6 |
| Sei | sei1gjrrme22cyha4ht2xapn3f08zzw6z3d4uxx6fyy9zd5dyr3yxgzqqncdqn |
| Seievm | 0xCa1D5a146B03f6303baF59e5AD5615ae0b9d146D |
| Sui | 0xaeab97f96cf9877fee2883315d459552b2b921edc16d7ceac6eab944dd88919c |
| Unichain | 0xCa1D5a146B03f6303baF59e5AD5615ae0b9d146D |
| World Chain | 0xcbcEe4e081464A15d8Ad5f58BB493954421eB506 |
| X Layer | 0x194B123c5E96B9b2E49763619985790Dc241CAC0 |
| XRPL-EVM | 0xaBf89de706B583424328B54dD05a8fC986750Da8 |
=== "Testnet"
| Ethereum Holesky | 0xa10f2eF61dE1f19f586ab8B6F2EbA89bACE63F7a |
| Ethereum Sepolia | 0x4a8bc80Ed5a4067f1CCf107057b8270E0cC11A78 |
| Solana | 3u8hJUVTA4jH1wYAyUur7FFZVQ8H635K3tSHHF4ssjQ5 |
| Algorand | 86525623 |
| Aptos | 0x5bc11445584a763c1fa7ed39081f1b920954da14e04b32440cba863d03e19625 |
| Arbitrum Sepolia | 0x6b9C8671cdDC8dEab9c719bB87cBd3e782bA6a35 |
| Avalanche | 0x7bbcE28e64B3F8b84d876Ab298393c38ad7aac4C |
| Base Sepolia | 0x79A1027a6A159502049F10906D333EC57E95F083 |
| Berachain | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| BNB Smart Chain | 0x68605AD7b15c732a30b1BbC62BE8F2A509D74b4D |
| Celo | 0x88505117CA88e7dd2eC6EA1E13f0948db2D50D56 |
| Converge | 0x556B259cFaCd9896B2773310080c7c3bcE90Ff01 |
| Fantom | 0x1BB3B4119b7BA9dfad76B0545fb3F531383c3bB7 |
| Fogo | BhnQyKoQQgpuRTRo6D8Emz93PvXCYfVgHhnrR4T3qhw4 |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| Injective | inj1xx3aupmgv3ce537c0yce8zzd3sz567syuyedpg |
| Ink | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| Kaia | 0x1830CC6eE66c84D2F177B94D544967c774E624cA |
| Linea | 0x79A1027a6A159502049F10906D333EC57E95F083 |
| Mantle | 0x376428e7f26D5867e69201b275553C45B09EE090 |
| Mezo | 0x268557122Ffd64c85750d630b716471118F323c8 |
| Monad | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| Moonbeam | 0xa5B7D85a8f27dd7907dc8FdC21FA5657D5E2F901 |
| NEAR | wormhole.wormhole.testnet |
| Neutron | neutron1enf63k37nnv9cugggpm06mg70emcnxgj9p64v2s8yx7a2yhhzk2q6xesk4 |
| Optimism Sepolia | 0x31377888146f3253211EFEf5c676D41ECe7D58Fe |
| Osmosis | osmo1hggkxr0hpw83f8vuft7ruvmmamsxmwk2hzz6nytdkzyup9krt0dq27sgyx |
| Plume | 0x81705b969cDcc6FbFde91a0C6777bE0EF3A75855 |
| Polygon Amoy | 0x6b9C8671cdDC8dEab9c719bB87cBd3e782bA6a35 |
| Pythnet | EUrRARh92Cdc54xrDn6qzaqjA77NRrCcfbr8kPwoTL4z |
| Scroll | 0x055F47F1250012C6B20c436570a76e52c17Af2D5 |
| Sei | sei1nna9mzp274djrgzhzkac2gvm3j27l402s4xzr08chq57pjsupqnqaj0d5s |
| Seievm | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| Sui | 0x31358d198147da50db32eda2562951d53973a0c0ad5ed738e9b17d88b213d790 |
| Unichain | 0xBB73cB66C26740F31d1FabDC6b7A46a038A300dd |
| World Chain | 0xe5E02cD12B6FcA153b0d7fF4bF55730AE7B3C93A |
| X Layer | 0xA31aa3FDb7aF7Db93d18DDA4e19F811342EDF780 |
| XRPL-EVM | 0xaBf89de706B583424328B54dD05a8fC986750Da8 |
=== "Devnet"
| Ethereum | 0xC89Ce4735882C9F0f0FE26686c53074E09B0D550 |
| Solana | Bridge1p5gheXUvJ6jGWGeCsgPKgnE3YgdGKRVCMY9o |
| Algorand | 1004 |
| Aptos | 0xde0036a9600559e295d5f6802ef6f3f802f510366e0c23912b0655d972166017 |
| BNB Smart Chain | 0xC89Ce4735882C9F0f0FE26686c53074E09B0D550 |
| NEAR | wormhole.test.near |
| Sui | 0x5a5160ca3c2037f4b4051344096ef7a48ebf4400b3f385e57ea90e1628a8bde0 |
## Wrapped Token Transfers (WTT)
=== "Mainnet"
| Ethereum | 0x3ee18B2214AFF97000D974cf647E7C347E8fa585 |
| Solana | wormDTUJ6AWPNvk59vGQbDvGJmqbDTdgWgAqcLBCgUb |
| Algorand | 842126029 |
| Aptos | 0x576410486a2da45eee6c949c995670112ddf2fbeedab20350d506328eefc9d4f |
| Arbitrum | 0x0b2402144Bb366A632D14B83F244D2e0e21bD39c |
| Avalanche | 0x0e082F06FF657D94310cB8cE8B0D9a04541d8052 |
| Base | 0x8d2de8d2f73F1F4cAB472AC9A881C9b123C79627 |
| Berachain | 0x3Ff72741fd67D6AD0668d93B41a09248F4700560 |
| BNB Smart Chain | 0xB6F6D86a8f9879A9c87f643768d9efc38c1Da6E7 |
| Celo | 0x796Dff6D74F3E27060B71255Fe517BFb23C93eed |
| Fantom | 0x7C9Fc5741288cDFdD83CeB07f3ea7e22618D79D2 |
| Injective | inj1ghd753shjuwexxywmgs4xz7x2q732vcnxxynfn |
| Ink | 0x3Ff72741fd67D6AD0668d93B41a09248F4700560 |
| Kaia | 0x5b08ac39EAED75c0439FC750d9FE7E1F9dD0193F |
| Mantle | 0x24850c6f61C438823F01B7A3BF2B89B72174Fa9d |
| Moonbeam | 0xb1731c586ca89a23809861c6103f0b96b3f57d92 |
| NEAR | contract.portalbridge.near |
| Optimism | 0x1D68124e65faFC907325e3EDbF8c4d84499DAa8b |
| Polygon | 0x5a58505a96D1dbf8dF91cB21B54419FC36e93fdE |
| Scroll | 0x24850c6f61C438823F01B7A3BF2B89B72174Fa9d |
| Sei | sei1smzlm9t79kur392nu9egl8p8je9j92q4gzguewj56a05kyxxra0qy0nuf3 |
| Seievm | 0x3Ff72741fd67D6AD0668d93B41a09248F4700560 |
| Sui | 0xc57508ee0d4595e5a8728974a4a93a787d38f339757230d441e895422c07aba9 |
| Unichain | 0x3Ff72741fd67D6AD0668d93B41a09248F4700560 |
| World Chain | 0xc309275443519adca74c9136b02A38eF96E3a1f6 |
| X Layer | 0x5537857664B0f9eFe38C9f320F75fEf23234D904 |
| XRPL-EVM | 0x47F5195163270345fb4d7B9319Eda8C64C75E278 |
=== "Testnet"
| Ethereum Holesky | 0x76d093BbaE4529a342080546cAFEec4AcbA59EC6 |
| Ethereum Sepolia | 0xDB5492265f6038831E89f495670FF909aDe94bd9 |
| Solana | DZnkkTmCiFWfYTfT41X3Rd1kDgozqzxWaHqsw6W4x2oe |
| Algorand | 86525641 |
| Aptos | 0x576410486a2da45eee6c949c995670112ddf2fbeedab20350d506328eefc9d4f |
| Arbitrum Sepolia | 0xC7A204bDBFe983FCD8d8E61D02b475D4073fF97e |
| Avalanche | 0x61E44E506Ca5659E6c0bba9b678586fA2d729756 |
| Base Sepolia | 0x86F55A04690fd7815A3D802bD587e83eA888B239 |
| Berachain | 0xa10f2eF61dE1f19f586ab8B6F2EbA89bACE63F7a |
| BNB Smart Chain | 0x9dcF9D205C9De35334D646BeE44b2D2859712A09 |
| Celo | 0x05ca6037eC51F8b712eD2E6Fa72219FEaE74E153 |
| Fantom | 0x599CEa2204B4FaECd584Ab1F2b6aCA137a0afbE8 |
| Fogo | 78HdStBqCMioGii9D8mF3zQaWDqDZBQWTUwjjpdmbJKX |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 0x4a8bc80Ed5a4067f1CCf107057b8270E0cC11A78 |
| Injective | inj1q0e70vhrv063eah90mu97sazhywmeegp7myvnh |
| Ink | 0x376428e7f26D5867e69201b275553C45B09EE090 |
| Kaia | 0xC7A13BE098720840dEa132D860fDfa030884b09A |
| Linea | 0xC7A204bDBFe983FCD8d8E61D02b475D4073fF97e |
| Mantle | 0x75Bfa155a9D7A3714b0861c8a8aF0C4633c45b5D |
| Mezo | 0xA31aa3FDb7aF7Db93d18DDA4e19F811342EDF780 |
| Monad | 0xF323dcDe4d33efe83cf455F78F9F6cc656e6B659 |
| Moonbeam | 0xbc976D4b9D57E57c3cA52e1Fd136C45FF7955A96 |
| NEAR | token.wormhole.testnet |
| Optimism Sepolia | 0x99737Ec4B815d816c49A385943baf0380e75c0Ac |
| Polygon Amoy | 0xC7A204bDBFe983FCD8d8E61D02b475D4073fF97e |
| Scroll | 0x22427d90B7dA3fA4642F7025A854c7254E4e45BF |
| Sei | sei1jv5xw094mclanxt5emammy875qelf3v62u4tl4lp5nhte3w3s9ts9w9az2 |
| Seievm | 0x23908A62110e21C04F3A4e011d24F901F911744A |
| Sui | 0x6fb10cdb7aa299e9a4308752dadecb049ff55a892de92992a1edbd7912b3d6da |
| Unichain | 0xa10f2eF61dE1f19f586ab8B6F2EbA89bACE63F7a |
| World Chain | 0x430855B4D43b8AEB9D2B9869B74d58dda79C0dB2 |
| X Layer | 0xdA91a06299BBF302091B053c6B9EF86Eff0f930D |
| XRPL-EVM | 0x7d8eBc211C4221eA18E511E4f0fD50c5A539f275 |
=== "Devnet"
| Ethereum | 0x0290FB167208Af455bB137780163b7B7a9a10C16 |
| Solana | B6RHG3mfcckmrYN1UhmJzyS1XX3fZKbkeUcpJe9Sy3FE |
| Algorand | 1006 |
| Aptos | 0x84a5f374d29fc77e370014dce4fd6a55b58ad608de8074b0be5571701724da31 |
| BNB Smart Chain | 0x0290FB167208Af455bB137780163b7B7a9a10C16 |
| NEAR | token.test.near |
| Sui | 0xa6a3da85bbe05da5bfd953708d56f1a3a023e7fb58e5a824a3d4de3791e8f690 |
## Wormhole Relayer
=== "Mainnet"
| Ethereum | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Arbitrum | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Avalanche | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Base | 0x706f82e9bb5b0813501714ab5974216704980e31 |
| Berachain | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| BNB Smart Chain | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Celo | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Fantom | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Ink | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Kaia | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Mantle | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Mezo | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Moonbeam | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Optimism | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Plume | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Polygon | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Scroll | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Seievm | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| Unichain | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
| World Chain | 0x1520cc9e779c56dab5866bebfb885c86840c33d3 |
| X Layer | 0x27428DD2d3DD32A4D7f7C497eAaa23130d894911 |
=== "Testnet"
| Ethereum Sepolia | 0x7B1bD7a6b4E61c2a123AC6BC2cbfC614437D0470 |
| Arbitrum Sepolia | 0x7B1bD7a6b4E61c2a123AC6BC2cbfC614437D0470 |
| Avalanche | 0xA3cF45939bD6260bcFe3D66bc73d60f19e49a8BB |
| Base Sepolia | 0x93BAD53DDfB6132b0aC8E37f6029163E63372cEE |
| Berachain | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| BNB Smart Chain | 0x80aC94316391752A193C1c47E27D382b507c93F3 |
| Celo | 0x306B68267Deb7c5DfCDa3619E22E9Ca39C374f84 |
| Fantom | 0x7B1bD7a6b4E61c2a123AC6BC2cbfC614437D0470 |
| Ink | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| Mezo | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| Monad | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| Moonbeam | 0x0591C25ebd0580E0d4F27A82Fc2e24E7489CB5e0 |
| Optimism Sepolia | 0x93BAD53DDfB6132b0aC8E37f6029163E63372cEE |
| Polygon Amoy | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| Seievm | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| Unichain | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
| XRPL-EVM | 0x362fca37E45fe1096b42021b543f462D49a5C8df |
=== "Devnet"
| Ethereum | 0xcC680D088586c09c3E0E099a676FA4b6e42467b4 |
| BNB Smart Chain | 0xcC680D088586c09c3E0E099a676FA4b6e42467b4 |
## CCTP
=== "Mainnet"
| Ethereum | 0xAaDA05BD399372f0b0463744C09113c137636f6a |
| Arbitrum | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
| Avalanche | 0x09Fb06A271faFf70A651047395AaEb6265265F13 |
| Base | 0x03faBB06Fa052557143dC28eFCFc63FC12843f1D |
| Optimism | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
| Polygon | 0x0FF28217dCc90372345954563486528aa865cDd6 |
=== "Testnet"
| Ethereum Sepolia | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
| Arbitrum Sepolia | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
| Avalanche | 0x58f4c17449c90665891c42e14d34aae7a26a472e |
| Base Sepolia | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
| Optimism Sepolia | 0x2703483B1a5a7c577e8680de9Df8Be03c6f30e3c |
=== "Devnet"
N/A
## Settlement Token Router
=== "Mainnet"
Chain Name
Contract Address
Ethereum
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
Solana
28topqjtJzMnPaGFmmZk68tzGmj9W9aMntaEK3QkgtRe
Arbitrum
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
Avalanche
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
Base
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
Optimism
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
Polygon
0x70287c79ee41C5D1df8259Cd68Ba0890cd389c47
=== "Testnet"
Chain Name
Contract Address
Solana
tD8RmtdcV7bzBeuFgyrFc8wvayj988ChccEzRQzo6md
Arbitrum Sepolia
0xe0418C44F06B0b0D7D1706E01706316DBB0B210E
Optimism Sepolia
0x6BAa7397c18abe6221b4f6C3Ac91C88a9faE00D8
## Guardian Governance
=== "Mainnet"
| Solana | NGoD1yTeq5KaURrZo7MnCTFzTA4g62ygakJCnzMLCfm |
| Ethereum | 0x23Fea5514DFC9821479fBE18BA1D7e1A61f6FfCf |
| Arbitrum | 0x36CF4c88FA548c6Ad9fcDc696e1c27Bb3306163F |
| Avalanche | 0x169D91C797edF56100F1B765268145660503a423 |
| Base | 0x838a95B6a3E06B6f11C437e22f3C7561a6ec40F1 |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | 0x574B7864119C9223A9870Ea614dC91A8EE09E512 |
| Optimism | 0x0E09a3081837ff23D2e59B179E0Bc48A349Afbd8 |
| Unichain | 0x574b7864119c9223a9870ea614dc91a8ee09e512 |
!!! note
Guardian-governed ownership contracts are used where an owner is required, without adding new trust assumptions. They only accept instructions signed by a quorum of Wormhole Guardians, validated on-chain by the Wormhole Core contracts. Implementations: [EVM](https://github.com/wormhole-foundation/native-token-transfers/blob/main/evm/src/wormhole/Governance.sol){target=\_blank} and [SVM](https://github.com/wormhole-foundation/native-token-transfers/blob/main/solana/programs/wormhole-governance/src/instructions/governance.rs){target=\_blank}.
## Read-Only Deployments
=== "Mainnet"
| Acala | 0xa321448d90d4e5b0A732867c18eA198e75CAC48E |
| Aurora | 0x51b5123a7b0F9b2bA265f9c4C8de7D78D52f510F |
| Blast | 0xbebdb6C8ddC678FfA9f8748f85C815C556Dd8ac6 |
| Corn | 0xa683c66045ad16abb1bCE5ad46A64d95f9A25785 |
| Gnosis | 0xa321448d90d4e5b0A732867c18eA198e75CAC48E |
| Goat | 0x352A86168e6988A1aDF9A15Cb00017AAd3B67155 |
| Karura | 0xa321448d90d4e5b0A732867c18eA198e75CAC48E |
| LightLink | 0x352A86168e6988A1aDF9A15Cb00017AAd3B67155 |
| Oasis | 0xfE8cD454b4A1CA468B57D79c0cc77Ef5B6f64585 |
| Rootstock | 0xbebdb6C8ddC678FfA9f8748f85C815C556Dd8ac6 |
| Sonic | 0x352A86168e6988A1aDF9A15Cb00017AAd3B67155 |
| Telos | 0x352A86168e6988A1aDF9A15Cb00017AAd3B67155 |
| Terra | terra1dq03ugtd40zu9hcgdzrsq6z2z4hwhc9tqk2uy5 |
| Terra 2.0 | terra12mrnzvhx3rpej6843uge2yyfppfyd3u9c3uq223q8sl48huz9juqffcnhp |
| SNAXchain | 0xc1BA3CC4bFE724A08FbbFbF64F8db196738665f4 |
| XPLA | xpla1jn8qmdda5m6f6fqu9qv46rt7ajhklg40ukpqchkejcvy8x7w26cqxamv3w |
!!! note
Read-only deployments allow Wormhole messages to be received on chains not fully integrated with Wormhole Guardians. These deployments support cross-chain data verification but cannot originate messages. For example, a governance message can be sent from a fully integrated chain and processed on a read-only chain, but the read-only chain cannot send messages back.
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/supported-networks.md
--- BEGIN CONTENT ---
---
title: Supported Networks
description: Learn about the networks each Wormhole product supports, and explore links to documentation, official websites, and block explorers.
categories: Reference
---
# Supported Networks
Wormhole supports many blockchains across mainnet, testnet, and devnets. You can use these tables to verify if your desired chains are supported by the Wormhole products you plan to include in your integration.
## Supported Networks by Product
### Connect
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/testnet-faucets.md
--- BEGIN CONTENT ---
---
title: Testnet Faucets
description: This page includes resources to quickly find the Testnet tokens you need to deploy and test applications and contracts on Wormhole's supported networks.
categories: Reference
---
# Testnet Faucets
Don't let the need for testnet tokens get in the way of buildling your next great idea with Wormhole. Use this guide to quickly locate the testnet token faucets you need to deploy and test applications and contracts on Wormhole's supported networks.
### EVM
| Ethereum Holesky | EVM | ETH | Alchemy Faucet |
| Ethereum Sepolia | EVM | ETH | Alchemy Faucet |
| Arbitrum Sepolia | EVM | ETH | List of Faucets |
| Avalanche | EVM | AVAX | Official Avalanche Faucet |
| Base Sepolia | EVM | ETH | List of Faucets |
| Berachain | EVM | BERA | Official Berachain Faucet |
| BNB Smart Chain | EVM | BNB | Official BNB Faucet |
| Celo | EVM | CELO | Official Celo Faucet |
| Fantom | EVM | FTM | Official Fantom Faucet |
| HyperEVM :material-alert:{ title='⚠️ The HyperEVM integration is experimental, as its node software is not open source. Use Wormhole messaging on HyperEVM with caution.' } | EVM | mock USDC | Official Hyperliquid Faucet |
| Ink | EVM | ETH | Official Ink Faucet |
| Kaia | EVM | KAIA | Official Kaia Faucet |
| Linea | EVM | ETH | List of Faucets |
| Mantle | EVM | MNT | Official Mantle Faucet |
| Monad | EVM | MON | Official Monad Faucet |
| Moonbeam | EVM | DEV | Official Moonbeam Faucet |
| Optimism Sepolia | EVM | ETH | Superchain Faucet |
| Plume | EVM | PLUME | Official Plume Faucet |
| Polygon Amoy | EVM | POL | Official Polygon Faucet |
| Scroll | EVM | ETH | List of Faucets |
| Seievm | EVM | SEI | Sei Atlantic-2 Faucet |
| Unichain | EVM | ETH | QuickNode Faucet |
| World Chain | EVM | ETH | Alchemy Faucet |
| X Layer | EVM | OKB | X Layer Official Faucet |
| XRPL-EVM | EVM | XRP | XRPL Official Faucet |
### SVM
| Pythnet | SVM | ETH | Superchain Faucet |
### AVM
| Algorand | AVM | ALGO | Official Algorand Faucet |
### CosmWasm
| Celestia | CosmWasm | TIA | Discord Faucet |
| Cosmos Hub | CosmWasm | ATOM | Discord Faucet |
| Evmos | CosmWasm | TEVMOS | Official Evmos Faucet |
| Injective | CosmWasm | INJ | Official Injective Faucet |
| Kujira | CosmWasm | KUJI | Discord Faucet |
| Neutron | CosmWasm | NTRN | List of Faucets |
| Noble | CosmWasm | USDC | Circle Faucet |
| Osmosis | CosmWasm | OSMO | Official Osmosis Faucet |
| SEDA | CosmWasm | SEDA | Official SEDA Faucet |
| Sei | CosmWasm | SEI | Sei Atlantic-2 Faucet |
### Move VM
| Aptos | Move VM | APT | Official Aptos Faucet |
### NEAR VM
| NEAR | NEAR VM | NEAR | Official NEAR Faucet |
### Sui Move VM
| Sui | Sui Move VM | SUI | List of Faucets |
--- END CONTENT ---
Doc-Content: https://raw.githubusercontent.com/wormhole-foundation/wormhole-docs/refs/heads/main/products/reference/wormhole-formatted-addresses.md
--- BEGIN CONTENT ---
---
title: Wormhole Formatted Addresses
description: Explanation of Wormhole formatted 32-byte hex addresses, their conversion, and usage across different blockchain platforms.
categories: Reference
---
# Wormhole Formatted Addresses
Wormhole formatted addresses are 32-byte hex representations of addresses from any supported blockchain. Whether an address originates from EVM, Solana, Cosmos, or another ecosystem, Wormhole standardizes all addresses into this format to ensure cross-chain compatibility.
This uniform format is essential for smooth interoperability in token transfers and messaging across chains. Wormhole uses formatted addresses throughout the [Wormhole SDK](https://github.com/wormhole-foundation/wormhole-sdk-ts){target=\_blank}, especially in cross-chain transactions, such as transfer functions that utilize the `bytes32` representation for recipient addresses.
## Platform-Specific Address Formats
Each blockchain ecosystem Wormhole supports has its method for formatting native addresses. To enable cross-chain compatibility, Wormhole converts these native addresses into the standardized 32-byte hex format.
Here’s an overview of the native address formats and how they are normalized to the Wormhole format:
| Platform | Native Address Format | Wormhole Formatted Address |
|-----------------|----------------------------------|----------------------------|
| EVM | Hex (e.g., 0x...) | 32-byte Hex |
| Solana | Base58 | 32-byte Hex |
| CosmWasm | Bech32 | 32-byte Hex |
| Algorand | Algorand App ID | 32-byte Hex |
| Sui | Hex | 32-byte Hex |
| Aptos | Hex | 32-byte Hex |
| Near | SHA-256 | 32-byte Hex |
These conversions allow Wormhole to interact seamlessly with various chains using a uniform format for all addresses.
### Address Format Handling
The Wormhole SDK provides mappings that associate each platform with its native address format. You can find this mapping in the Wormhole SDK file [`platforms.ts`](https://github.com/wormhole-foundation/wormhole-sdk-ts/blob/007f61b27c650c1cf0fada2436f79940dfa4f211/core/base/src/constants/platforms.ts#L93-L102){target=\_blank}:
```typescript
const platformAddressFormatEntries = [
['Evm', 'hex'],
['Solana', 'base58'],
['Cosmwasm', 'bech32'],
['Algorand', 'algorandAppId'],
['Sui', 'hex'],
['Aptos', 'hex'],
['Near', 'sha256'],
];
```
These entries define how the [`UniversalAddress`](https://github.com/wormhole-foundation/wormhole-sdk-ts/blob/007f61b27c650c1cf0fada2436f79940dfa4f211/core/definitions/src/universalAddress.ts#L23){target=\_blank} class handles different address formats based on the platform.
## Universal Address Methods
The `UniversalAddress` class is essential for working with Wormhole formatted addresses. It converts native blockchain addresses into the standardized 32-byte hex format used across Wormhole operations.
Key functions:
- **`new UniversalAddress()`**: Use the `UniversalAddress` constructor to convert native addresses into the Wormhole format.
```typescript
const universalAddress = new UniversalAddress('0x123...', 'hex');
```
- **`toUniversalAddress()`**: Converts a platform-specific address into the Wormhole formatted 32-byte hex address.
```typescript
const ethAddress: NativeAddress<'Evm'> = toNative('Ethereum', '0x0C9...');
const universalAddress = ethAddress.toUniversalAddress().toString();
```
- **`toNative()`**: Converts the Wormhole formatted address back to a native address for a specific blockchain platform.
```typescript
const nativeAddress = universalAddress.toNative('Evm');
```
- **`toString()`**: Returns the Wormhole formatted address as a hex string, which can be used in various SDK operations.
```typescript
console.log(universalAddress.toString());
```
These methods allow developers to convert between native addresses and the Wormhole format, ensuring cross-chain compatibility.
## Convert Between Native and Wormhole Formatted Addresses
The Wormhole SDK allows developers to easily convert between native addresses and Wormhole formatted addresses when building cross-chain applications.
### Convert a Native Address to a Wormhole Formatted Address
Example conversions for EVM and Solana:
=== "EVM"
```typescript
import { toNative } from '@wormhole-foundation/sdk-core';
const ethAddress: NativeAddress<'Evm'> = toNative(
'Ethereum',
'0x0C99567DC6f8f1864cafb580797b4B56944EEd28'
);
const universalAddress = ethAddress.toUniversalAddress().toString();
console.log('Universal Address (EVM):', universalAddress);
```
=== "Solana"
```typescript
import { toNative } from '@wormhole-foundation/sdk-core';
const solAddress: NativeAddress<'Solana'> = toNative(
'Solana',
'6zZHv9EiqQYcdg52ueADRY6NbCXa37VKPngEHaokZq5J'
);
const universalAddressSol = solAddress.toUniversalAddress().toString();
console.log('Universal Address (Solana):', universalAddressSol);
```
The result is a standardized address format that is ready for cross-chain operations.
### Convert Back to Native Addresses
Below is how you can convert a Wormhole formatted address back to an EVM or Solana native address:
```typescript
const nativeAddressEvm = universalAddress.toNative('Evm');
console.log('EVM Native Address:', nativeAddressEvm);
const nativeAddressSolana = universalAddress.toNative('Solana');
console.log('Solana Native Address:', nativeAddressSolana);
```
These conversions ensure that your cross-chain applications can seamlessly handle addresses across different ecosystems.
## Use Cases for Wormhole Formatted Addresses
### Cross-chain Token Transfers
Cross-chain token transfers require addresses to be converted into a standard format. For example, when transferring tokens from Ethereum to Solana, the Ethereum address is converted into a Wormhole formatted address to ensure compatibility. After the transfer, the Wormhole formatted address is converted back into the Solana native format.
### Smart Contract Interactions
In smart contract interactions, especially when building dApps that communicate across multiple chains, Wormhole formatted addresses provide a uniform way to reference addresses. This ensures that addresses from different blockchains can interact seamlessly, whether you're sending messages or making cross-chain contract calls.
### DApp Development
For cross-chain dApp development, Wormhole formatted addresses simplify handling user wallet addresses across various blockchains. This allows developers to manage addresses consistently, regardless of whether they work with EVM, Solana, or another supported platform.
### Relayers and Infrastructure
Finally, relayers and infrastructure components, such as Wormhole Guardians, rely on the standardized format to efficiently process and relay cross-chain messages. A uniform address format simplifies operations, ensuring smooth interoperability across multiple blockchains.
--- END CONTENT ---