# Enable your tokens in CCIP (Burn & Mint): Register from an EOA using Hardhat Source: https://docs.chain.link/ccip/tutorials/evm/cross-chain-tokens/register-from-eoa-burn-mint-hardhat Last Updated: 2025-10-22 This tutorial will guide you through the process of enabling your own tokens in CCIP using [Hardhat](https://hardhat.org/). You will learn how to deploy tokens and set up *Burn & Mint* token pools. After that, you will register them in CCIP and configure them without needing manual intervention. Finally, you will test the **Burn & Mint** token handling mechanism, where tokens are burned on the source blockchain and an equivalent amount is minted on the destination blockchain. We will cover the following key steps: 1. **Deploying Tokens**: You will deploy your [`BurnMintERC20`](https://github.com/smartcontractkit/chainlink-evm/blob/contracts-solidity/1.5.0/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol) tokens on the Avalanche Fuji and Arbitrum Sepolia testnets. 2. **Deploying Token Pools**: Once your tokens are deployed, you will deploy [`BurnMintTokenPool`](/ccip/api-reference/evm/v1.6.1/burn-mint-token-pool) token pools on Avalanche Fuji and Arbitrum Sepolia. These pools are essential for minting and burning tokens during cross-chain transfers. Each token will be linked to a pool, which will manage token transfers and ensure proper handling of assets across chains. 3. **Claiming Mint and Burn Roles**: You will [claim the mint and burn roles](https://github.com/smartcontractkit/chainlink-evm/blob/contracts-solidity/1.5.0/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol#L142) for the token pools, allowing your token pools to control how tokens are minted and burned during cross-chain transfers. 4. **Claiming and Accepting the Admin Role**: This is a two-step process: 1. You will call the [`RegistryModuleOwnerCustom`](/ccip/api-reference/evm/v1.6.1/registry-module-owner-custom) contract's [`registerAdminViaOwner`](/ccip/api-reference/evm/v1.6.1/registry-module-owner-custom#registeradminviaowner) function to register your EOA as the token admin. This role is required to enable your token in CCIP. 2. Once claimed, you will call the [`TokenAdminRegistry`](/ccip/api-reference/evm/v1.6.1/token-admin-registry) contract's [`acceptAdminRole`](/ccip/api-reference/evm/v1.6.1/token-admin-registry#acceptadminrole) function to complete the registration process. 5. **Linking Tokens to Pools**: You will call the [`TokenAdminRegistry`](/ccip/api-reference/evm/v1.6.1/token-admin-registry) contract's [`setPool`](/ccip/api-reference/evm/v1.6.1/token-admin-registry#setpool) function to associate each token with its respective token pool. 6. **Configuring Token Pools**: You will call the [`applyChainUpdates`](/ccip/api-reference/evm/v1.6.1/token-pool#applychainupdates) function on your token pools to configure each pool by setting cross-chain transfer parameters, such as token pool rate limits and enabled destination chains. 7. **Minting Tokens**: You will call the [`mint`](https://github.com/smartcontractkit/chainlink-evm/blob/contracts-solidity/1.5.0/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol#L128) function to mint tokens on Avalanche Fuji for your EOA. These tokens will later be used to test cross-chain transfers to Arbitrum Sepolia. 8. **Transferring Tokens**: Finally, you will transfer tokens from Avalanche Fuji to Arbitrum Sepolia using CCIP. You will have the option to pay CCIP fees in either LINK tokens or native gas tokens. By the end of this tutorial, you will have successfully deployed, registered, configured, and enabled your tokens and token pools for use in CCIP. ## Before You Begin 1. Make sure you have Node.js v22.10.0 or above installed. If not, **install Node.js v22.10.0**: [Download Node.js v22.10.0](https://nodejs.org/en/download/) if you don't have it installed. Optionally, you can use the [nvm package](https://www.npmjs.com/package/nvm) to switch between Node.js versions: ```bash nvm use 22 ``` Verify that the correct version of Node.js is installed: ```bash node -v ``` Example output: ```bash $ node -v v22.15.0 ``` > **CAUTION: Why Node.js v22?** > > Since the [migration](https://hardhat.org/migrate-from-hardhat2) to Hardhat 3.x, Node.js v22.10.0 or above is > [required for compatibility](https://hardhat.org/migrate-from-hardhat2#before-starting-the-migration). Using an > older version may lead to unexpected issues during development. 1. **Clone the repository and navigate to the project directory:** ```bash git clone https://github.com/smartcontractkit/smart-contract-examples.git cd smart-contract-examples/ccip/cct/hardhat ``` 2. **Install dependencies for the project:** ```bash npm install ``` 3. **Compile the project:** ```bash npm run compile ``` 4. **Encrypt your environment variables for higher security:**\ The project uses [@chainlink/env-enc](https://www.npmjs.com/package/@chainlink/env-enc) to encrypt your environment variables at rest. Follow the steps below to configure your environment securely: 1. Set an encryption password for your environment variables: ```bash npx env-enc set-pw ``` 2. Set up a `.env.enc` file with the necessary variables for Avalanche Fuji and Ethereum Sepolia. Use the following command to add the variables: ```bash npx env-enc set ``` Variables to configure: - `AVALANCHE_FUJI_RPC_URL`: A URL for the *Avalanche Fuji* testnet. You can get a personal endpoint from services like [Alchemy](https://www.alchemy.com/) or [Infura](https://www.infura.io/). - `ETHEREUM_SEPOLIA_RPC_URL`: A URL for the *Ethereum Sepolia* testnet. You can sign up for a personal endpoint from [Alchemy](https://www.alchemy.com/) or [Infura](https://www.infura.io/). - `PRIVATE_KEY`: The private key for your testnet wallet. If you use MetaMask, you can follow this [guide](https://support.metamask.io/managing-my-wallet/secret-recovery-phrase-and-private-keys/how-to-export-an-accounts-private-key/) to export your private key. **Note:** This key is required for signing transactions like token transfers. - `ETHERSCAN_API_KEY`: An API key from Etherscan to verify your contracts. You can obtain one from [Etherscan](https://docs.etherscan.io/getting-started/viewing-api-usage-statistics). 5. **Fund your EOA with LINK and native gas tokens**:\ Make sure your EOA has enough LINK and native gas tokens on Avalanche Fuji and Ethereum Sepolia to cover transaction fees. You can use the [Chainlink faucets](https://faucets.chain.link/) to get testnet tokens. > **NOTE: Using Different Networks** > > This tutorial uses Avalanche Fuji and Ethereum Sepolia by default. To test with other CCIP-supported networks, see > [Add CCIP Networks for Cross-Chain Token > Tutorials](/ccip/tutorials/evm/cross-chain-tokens/configure-additional-networks-hardhat). ## Tutorial > **NOTE: Explore the Code** > > All Hardhat tasks used in this tutorial are located in the `tasks/` directory of the repository. Each task is > thoroughly commented and directly linked to a key step in the tutorial, making the code self-explanatory. Read the > code and comments to gain a deeper understanding of the process or explore the implementation details. ### Deploy Tokens In this step, you will use the `deployToken` task to deploy tokens on two testnets, Avalanche Fuji and Ethereum Sepolia. Below is an explanation of the parameters used during deployment: | Parameter | Description | Default | Required | | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | -------- | | `name` | The name of the token. This is the full name by which the token will be identified. | N/A | Yes | | `symbol` | The symbol of the token. This is the shorthand (usually 3-5 letters) representing the token. | N/A | Yes | | `decimals` | The number of decimals the token will use. For instance, `18` decimals means 1 token is represented as `1e18` smallest units. | `18` | No | | `maxsupply` | The maximum supply of tokens. Use `0` for unlimited supply. | `0` | No | | `premint` | The amount of tokens to be minted to the owner at the time of deployment. If set to `0`, no tokens will be minted to the owner during deployment. | `0` | No | | `verifycontract` | Flag to verify the contract on Etherscan or a similar blockchain explorer. Pass this flag to enable verification, omit to skip. | `false` | No | | `network` | The blockchain on which the token will be deployed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | Deploy tokens, use the following commands, substituting the token name and symbol as needed: 1. **Deploy the token on Avalanche Fuji:** ```bash npx hardhat deployToken --name "BnM sak" --symbol BnMsak --decimals 18 --maxsupply 0 --premint 100000000000000000000 --verifycontract --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T15:48:05.691Z info: 🚀 Deploying BurnMintERC20 to avalancheFuji... 2025-10-21T15:48:05.692Z info: name: BnM sak, symbol: BnMsak 2025-10-21T15:48:43.684Z info: ⏳ Deployment tx: 0x36109e1ff82c5063e231e036ea9d4d0d66421ff5edd61a0d5767e95793f54eb5 2025-10-21T15:48:43.684Z info: Waiting for 2 confirmation(s)... 2025-10-21T15:49:07.361Z info: ✅ Token deployed at: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T15:49:09.119Z info: Granting mint and burn roles to 0x8C244f0B2164E6A3BED74ab429B0ebd661Bb14CA... 2025-10-21T15:49:10.392Z info: Waiting for 2 confirmation(s)... 2025-10-21T15:50:20.800Z info: ✅ Mint/Burn roles granted. 2025-10-21T15:50:20.801Z info: Verifying contract... 📤 Submitted source code for verification on SnowTrace: @chainlink/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol:BurnMintERC20 Address: 0xb613B55897F07eAF430bF9a509498e55487305Ea ⏳ Waiting for verification result... ✅ Contract verified successfully on SnowTrace! @chainlink/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol:BurnMintERC20 Explorer: https://testnet.snowtrace.io/address/0xb613B55897F07eAF430bF9a509498e55487305Ea#code 2025-10-21T15:50:30.197Z info: ✅ Token contract verified successfully ``` 2. **Deploy the token on Ethereum Sepolia:** ```bash npx hardhat deployToken --name "BnM sak" --symbol BnMsak --decimals 18 --maxsupply 0 --premint 100000000000000000000 --verifycontract --network ethereumSepolia ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T15:57:35.979Z info: 🚀 Deploying BurnMintERC20 to ethereumSepolia... 2025-10-21T15:57:35.980Z info: name: BnM sak, symbol: BnMsak 2025-10-21T15:57:47.934Z info: ⏳ Deployment tx: 0xa1559da1474d9a062a63b57f86e4c6047c8918778b4abe5c7f911a85b502094b 2025-10-21T15:57:47.934Z info: Waiting for 3 confirmation(s)... 2025-10-21T15:58:54.199Z info: ✅ Token deployed at: 0x6803e72f0af827577a49FC82d7Ed9291028d687c 2025-10-21T15:58:55.814Z info: Granting mint and burn roles to 0x8C244f0B2164E6A3BED74ab429B0ebd661Bb14CA... 2025-10-21T15:59:00.841Z info: Waiting for 3 confirmation(s)... 2025-10-21T15:59:37.640Z info: ✅ Mint/Burn roles granted. 2025-10-21T15:59:37.640Z info: Verifying contract... 📤 Submitted source code for verification on Etherscan: @chainlink/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol:BurnMintERC20 Address: 0x6803e72f0af827577a49FC82d7Ed9291028d687c ⏳ Waiting for verification result... ✅ Contract verified successfully on Etherscan! @chainlink/contracts/src/v0.8/shared/token/ERC20/BurnMintERC20.sol:BurnMintERC20 Explorer: https://sepolia.etherscan.io/address/0x6803e72f0af827577a49FC82d7Ed9291028d687c#code 2025-10-21T16:00:05.431Z info: ✅ Token contract verified successfully ``` ### Deploy Token Pools > **CAUTION: Understand Token Pool Requirements** > > Before deploying your token pools, make sure you understand the mandatory requirements for token pools and the gas > limit restrictions. The `releaseOrMint` function and other operations (e.g., balance checks) must not exceed the > **90,000** gas limit on the destination blockchain. Failure to meet these requirements can lead to [manual > execution](/ccip/concepts/manual-execution). For more details, refer to the [Common > Requirements](/ccip/concepts/cross-chain-token/evm/token-pools#common-requirements). In this step, you will use the `deployTokenPool` task to deploy token pools for the tokens on both testnets, Avalanche Fuji and Ethereum Sepolia. Below is an explanation of the parameters used during deployment: | Parameter | Description | Default | Required | | -------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------- | ------------ | -------- | | `tokenaddress` | The address of the token for which the pool is being created. | N/A | Yes | | `pooltype` | The type of pool to deploy. For this tutorial, we use `"burnMint"` for a pool that supports burning and minting of tokens. | `"burnMint"` | No | | `localtokendecimals` | The number of decimals for the token on this chain. | `18` | No | | `verifycontract` | Flag to verify the contract on Etherscan or a similar blockchain explorer. Pass this flag to enable verification, omit to skip. | `false` | No | | `network` | The blockchain on which the token pool will be deployed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | > **NOTE: Token Decimal Handling** > > If you need to handle tokens with different decimals across blockchains, refer to the [Token Decimal > Handling](/ccip/concepts/cross-chain-token/evm/token-pools#token-decimal-handling) section. Deploy token pools using the following commands, replacing the token address with the one you deployed in the previous step: 1. **Deploy the burn and mint token pool on Avalanche Fuji:** ```bash npx hardhat deployTokenPool \ --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea \ --pooltype burnMint \ --localtokendecimals 18 \ --verifycontract \ --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:03:29.749Z info: 🚀 Deploying burnMint pool on avalancheFuji 2025-10-21T16:03:29.750Z info: Token: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T16:03:29.750Z info: Decimals: 18 2025-10-21T16:03:29.750Z info: Allowlist: None 2025-10-21T16:04:31.691Z info: ⏳ Deployment tx: 0xc91a7fb0f1e77531bc49e9ce3c4de5f0bf8797e9e031e23c707b22b50fbb1547 2025-10-21T16:04:31.692Z info: Waiting for 2 confirmation(s)... 2025-10-21T16:04:32.196Z info: ✅ Token pool deployed at: 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A 2025-10-21T16:04:32.196Z info: Granting mint and burn roles to 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A on token 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T16:04:33.856Z info: Waiting for 2 confirmation(s)... 2025-10-21T16:05:45.050Z info: ✅ Mint/Burn roles granted 2025-10-21T16:05:45.051Z info: Verifying contract... 📤 Submitted source code for verification on SnowTrace: @chainlink/contracts-ccip/contracts/pools/BurnMintTokenPool.sol:BurnMintTokenPool Address: 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A ⏳ Waiting for verification result... ✅ Contract verified successfully on SnowTrace! @chainlink/contracts-ccip/contracts/pools/BurnMintTokenPool.sol:BurnMintTokenPool Explorer: https://testnet.snowtrace.io/address/0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A#code 2025-10-21T16:05:59.699Z info: ✅ Token pool contract verified successfully ``` 2. **Deploy the burn and mint token pool on Ethereum Sepolia:** ```bash npx hardhat deployTokenPool \ --tokenaddress 0x6803e72f0af827577a49FC82d7Ed9291028d687c \ --pooltype burnMint \ --localtokendecimals 18 \ --verifycontract \ --network ethereumSepolia ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:08:04.592Z info: 🚀 Deploying burnMint pool on ethereumSepolia 2025-10-21T16:08:04.593Z info: Token: 0x6803e72f0af827577a49FC82d7Ed9291028d687c 2025-10-21T16:08:04.593Z info: Decimals: 18 2025-10-21T16:08:04.593Z info: Allowlist: None 2025-10-21T16:08:31.645Z info: ⏳ Deployment tx: 0x10e0b153a0a3e3fe3eccd512403fa01aa8c4a9c017e2f15293da85bf3d0fbc55 2025-10-21T16:08:31.645Z info: Waiting for 3 confirmation(s)... 2025-10-21T16:08:51.518Z info: ✅ Token pool deployed at: 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D 2025-10-21T16:08:51.518Z info: Granting mint and burn roles to 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D on token 0x6803e72f0af827577a49FC82d7Ed9291028d687c 2025-10-21T16:08:57.229Z info: Waiting for 3 confirmation(s)... 2025-10-21T16:09:27.333Z info: ✅ Mint/Burn roles granted 2025-10-21T16:09:27.333Z info: Verifying contract... 📤 Submitted source code for verification on Etherscan: @chainlink/contracts-ccip/contracts/pools/BurnMintTokenPool.sol:BurnMintTokenPool Address: 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D ⏳ Waiting for verification result... ✅ Contract verified successfully on Etherscan! @chainlink/contracts-ccip/contracts/pools/BurnMintTokenPool.sol:BurnMintTokenPool Explorer: https://sepolia.etherscan.io/address/0xA29878301cA30a4639C33cD7EC8061E4265E1a5D#code 2025-10-21T16:09:53.510Z info: ✅ Token pool contract verified successfully ``` ### Claim Admin In this step, you will use the `claimAdmin` task to register your EOA as the administrator for the deployed tokens on both testnets, Avalanche Fuji and Ethereum Sepolia. This process involves calling the `RegistryModuleOwnerCustom` contract, which will fetch the CCIP admin of the token and set it up as the admin in the registry. Below is an explanation of the parameters used during the admin claim process: | Parameter | Description | Default | Required | | -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------- | -------- | | `tokenaddress` | The address of the token for which the admin role is being claimed. | N/A | Yes | | `network` | The blockchain on which the claim admin process will be executed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | Claim the admin role by using the following commands, replacing the token address with the one you deployed in the previous steps: 1. **Claim the admin role on Avalanche Fuji:** ```bash npx hardhat claimAdmin --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:28:08.196Z info: 🎯 Claiming admin for 0xb613B55897F07eAF430bF9a509498e55487305Ea using getCCIPAdmin mode 2025-10-21T16:28:11.832Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is CCIP admin 2025-10-21T16:29:04.511Z info: 📤 TX sent: 0xa15fcb890ac37b81d3ecec9560624e38b7d127177c01af7d9359ab5f6b6ca97c. Waiting for 2 confirmations... 2025-10-21T16:29:13.730Z info: ✅ Admin claimed for 0xb613B55897F07eAF430bF9a509498e55487305Ea on avalancheFuji (2 confirmations) ``` 2. **Claim the admin role on Ethereum Sepolia:** ```bash npx hardhat claimAdmin --tokenaddress 0x6803e72f0af827577a49FC82d7Ed9291028d687c --network ethereumSepolia ``` Example output: ```bash 2025-10-21T16:30:14.261Z info: 🎯 Claiming admin for 0x6803e72f0af827577a49FC82d7Ed9291028d687c using getCCIPAdmin mode 2025-10-21T16:30:23.319Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is CCIP admin 2025-10-21T16:30:30.196Z info: 📤 TX sent: 0x5c7e4644fc88d8df99ce8557665a78037951c748c927b012bb4565285241ae3a. Waiting for 3 confirmations... 2025-10-21T16:31:02.943Z info: ✅ Admin claimed for 0x6803e72f0af827577a49FC82d7Ed9291028d687c on ethereumSepolia (3 confirmations) ``` ### Accept Admin Role In this step, you will use the `acceptAdminRole` task to accept the admin role for the deployed tokens on both testnets, Avalanche Fuji and Ethereum Sepolia. Once you have claimed the role, accepting the role finalizes your control over the token administration. Below is an explanation of the parameters used during the admin role acceptance process: | Parameter | Description | Default | Required | | -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | -------- | | `tokenaddress` | The address of the token for which the admin role is being accepted. | N/A | Yes | | `network` | The blockchain on which the accept admin process will be executed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | Accept the admin role by using the following commands, replacing the token address with the one deployed in the previous steps: 1. **Accept the admin role on Avalanche Fuji:** ```bash npx hardhat acceptAdminRole --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:32:22.560Z info: 🔄 Accepting admin role for 0xb613B55897F07eAF430bF9a509498e55487305Ea on avalancheFuji... 2025-10-21T16:32:25.385Z info: Checking pending admin for 0xb613B55897F07eAF430bF9a509498e55487305Ea... 2025-10-21T16:32:25.641Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is the pending admin 2025-10-21T16:32:25.641Z info: Accepting admin role... 2025-10-21T16:33:07.931Z info: 📤 TX sent: 0xa7b57a5d7c29828ddf4941c48877c02d36cbc5ec9a4ba401548fef9163256abb. Waiting for 2 confirmations... 2025-10-21T16:33:24.516Z info: ✅ Admin role accepted for 0xb613B55897F07eAF430bF9a509498e55487305Ea on avalancheFuji (2 confirmations) ``` 2. **Accept the admin role on Ethereum Sepolia:** ```bash npx hardhat acceptAdminRole --tokenaddress 0x6803e72f0af827577a49FC82d7Ed9291028d687c --network ethereumSepolia ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:35:18.634Z info: 🔄 Accepting admin role for 0x6803e72f0af827577a49FC82d7Ed9291028d687c on ethereumSepolia... 2025-10-21T16:35:26.364Z info: Checking pending admin for 0x6803e72f0af827577a49FC82d7Ed9291028d687c... 2025-10-21T16:35:26.688Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is the pending admin 2025-10-21T16:35:26.688Z info: Accepting admin role... 2025-10-21T16:35:29.020Z info: 📤 TX sent: 0x5ede40fac823712bfa465f30258dcb5c90a3863f10db4e92d83d5165965221cd. Waiting for 3 confirmations... 2025-10-21T16:36:02.952Z info: ✅ Admin role accepted for 0x6803e72f0af827577a49FC82d7Ed9291028d687c on ethereumSepolia (3 confirmations) ``` ### Set Pool In this step, you will use the `setPool` task to link each token with its respective token pool on both testnets. Below is an explanation of the parameters used during the pool setting process: | Parameter | Description | Default | Required | | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | -------- | | `tokenaddress` | The address of the token to be linked to a pool. | N/A | Yes | | `pooladdress` | The address of the pool associated with the token. | N/A | Yes | | `network` | The blockchain on which the pool setting will be executed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | Link each token with its respective token pool by using the following commands, replacing the token and pool addresses with the ones you deployed in the previous steps: 1. **Set the pool for Avalanche Fuji:** ```bash npx hardhat setPool --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --pooladdress 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:37:52.758Z info: 🔗 Setting pool for token 0xb613B55897F07eAF430bF9a509498e55487305Ea on avalancheFuji... 2025-10-21T16:37:55.823Z info: 🔹 Using signer: 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca 2025-10-21T16:37:55.823Z info: Using TokenAdminRegistry: 0xA92053a4a3922084d992fD2835bdBa4caC6877e6 2025-10-21T16:37:56.225Z info: Checking token configuration for 0xb613B55897F07eAF430bF9a509498e55487305Ea... 2025-10-21T16:37:56.471Z info: Token 0xb613B55897F07eAF430bF9a509498e55487305Ea current admin: 0x8C244f0B2164E6A3BED74ab429B0ebd661Bb14CA 2025-10-21T16:37:56.471Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is the token administrator 2025-10-21T16:37:56.471Z info: Setting pool 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A for token 0xb613B55897F07eAF430bF9a509498e55487305Ea... 2025-10-21T16:38:05.847Z info: 📤 TX sent: 0xc06c155a0a581a83cadec3e6c2d41f1291c255f27fd9a2bfccaa349e8d22527f. Waiting for 2 confirmations... 2025-10-21T16:39:22.658Z info: ✅ Pool successfully set for token 0xb613B55897F07eAF430bF9a509498e55487305Ea → 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A on avalancheFuji (2 confirmations) ``` 2. **Set the pool for Ethereum Sepolia:** ```bash npx hardhat setPool --tokenaddress 0x6803e72f0af827577a49FC82d7Ed9291028d687c --pooladdress 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D --network ethereumSepolia ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:42:30.911Z info: 🔗 Setting pool for token 0x6803e72f0af827577a49FC82d7Ed9291028d687c on ethereumSepolia... 2025-10-21T16:42:39.838Z info: 🔹 Using signer: 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca 2025-10-21T16:42:39.838Z info: Using TokenAdminRegistry: 0x95F29FEE11c5C55d26cCcf1DB6772DE953B37B82 2025-10-21T16:42:40.266Z info: Checking token configuration for 0x6803e72f0af827577a49FC82d7Ed9291028d687c... 2025-10-21T16:42:40.702Z info: Token 0x6803e72f0af827577a49FC82d7Ed9291028d687c current admin: 0x8C244f0B2164E6A3BED74ab429B0ebd661Bb14CA 2025-10-21T16:42:40.702Z info: ✅ Current wallet 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca is the token administrator 2025-10-21T16:42:40.702Z info: Setting pool 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D for token 0x6803e72f0af827577a49FC82d7Ed9291028d687c... 2025-10-21T16:42:45.309Z info: 📤 TX sent: 0x994e1e97275ee1ed7b0135afdf8b85071899036bde490602590cda05ab7e5dda. Waiting for 3 confirmations... 2025-10-21T16:43:16.490Z info: ✅ Pool successfully set for token 0x6803e72f0af827577a49FC82d7Ed9291028d687c → 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D on ethereumSepolia (3 confirmations) ``` ### Configure Token Pools In this step, you will use the `applyChainUpdates` task to initialize the token pool configuration on each blockchain to enable cross-chain transfers between Avalanche Fuji and Ethereum Sepolia. Below is an explanation of the parameters used: | Parameter | Description | Default | Required | | --------------------------- | --------------------------------------------------------------------------------------------------------- | ------- | -------- | | `pooladdress` | The address of the pool to be configured. | N/A | Yes | | `remotechain` | The remote blockchain network (e.g., `ethereumSepolia` for Fuji pool, `avalancheFuji` for Sepolia pool). | N/A | Yes | | `remotepooladdresses` | Comma-separated list of remote pool addresses. | N/A | Yes | | `remotetokenaddress` | The address of the token on the remote chain. | N/A | Yes | | `outboundratelimitenabled` | Flag to enable outbound rate limits for cross-chain transfers. Pass this flag to enable, omit to disable. | `false` | No | | `outboundratelimitcapacity` | Maximum capacity for the outbound rate limiter (in wei). | `0` | No | | `outboundratelimitrate` | Refill rate for the outbound rate limiter bucket (tokens per second, in wei). | `0` | No | | `inboundratelimitenabled` | Flag to enable inbound rate limits for cross-chain transfers. Pass this flag to enable, omit to disable. | `false` | No | | `inboundratelimitcapacity` | Maximum capacity for the inbound rate limiter (in wei). | `0` | No | | `inboundratelimitrate` | Refill rate for the inbound rate limiter bucket (tokens per second, in wei). | `0` | No | Configure the pools using the following commands, replacing the pool, token, and remote pool addresses with those you deployed in the previous steps: 1. **Configure the pool on Avalanche Fuji:** ```bash npx hardhat applyChainUpdates \ --pooladdress 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A \ --remotechain ethereumSepolia \ --remotepooladdresses 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D \ --remotetokenaddress 0x6803e72f0af827577a49FC82d7Ed9291028d687c \ --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:51:34.417Z info: === Starting Chain Update Configuration === 2025-10-21T16:51:34.418Z info: 🔹 Local network: avalancheFuji 2025-10-21T16:51:34.418Z info: 🔹 Pool address: 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A 2025-10-21T16:51:34.418Z info: 🔹 Remote chain: ethereumSepolia 2025-10-21T16:51:34.418Z info: 🔹 Remote chain family: evm 2025-10-21T16:51:34.418Z info: 🔹 Remote chain selector: 16015286601757825753 2025-10-21T16:51:36.581Z info: ✅ All addresses validated successfully 2025-10-21T16:51:37.100Z info: ✅ Using signer: 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca 2025-10-21T16:51:37.504Z info: ✅ Connected to TokenPool contract 2025-10-21T16:51:37.505Z info: Remote pool 1: 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D → 0x000000000000000000000000a29878301ca30a4639c33cd7ec8061e4265e1a5d 2025-10-21T16:51:37.506Z info: === Rate Limiter Configuration === 2025-10-21T16:51:37.506Z info: Outbound enabled: false 2025-10-21T16:51:37.506Z info: Inbound enabled: false 2025-10-21T16:51:37.506Z info: === Executing applyChainUpdates() === 2025-10-21T16:52:05.003Z info: 📤 TX sent: 0xde6b43d51e34668267eccdb188402b12c3e7497a918f17dd93521c504efc22db 2025-10-21T16:52:05.003Z info: Waiting for 2 confirmations... 2025-10-21T16:52:21.542Z info: ✅ Chain update applied successfully on avalancheFuji (2 confirmations)! ``` 2. **Configure the pool on Ethereum Sepolia:** ```bash npx hardhat applyChainUpdates \ --pooladdress 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D \ --remotechain avalancheFuji \ --remotetokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea \ --remotepooladdresses 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A \ --network ethereumSepolia ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T16:59:10.675Z info: === Starting Chain Update Configuration === 2025-10-21T16:59:10.676Z info: 🔹 Local network: ethereumSepolia 2025-10-21T16:59:10.676Z info: 🔹 Pool address: 0xA29878301cA30a4639C33cD7EC8061E4265E1a5D 2025-10-21T16:59:10.676Z info: 🔹 Remote chain: avalancheFuji 2025-10-21T16:59:10.676Z info: 🔹 Remote chain family: evm 2025-10-21T16:59:10.676Z info: 🔹 Remote chain selector: 14767482510784806043 2025-10-21T16:59:12.799Z info: ✅ All addresses validated successfully 2025-10-21T16:59:13.366Z info: ✅ Using signer: 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca 2025-10-21T16:59:13.699Z info: ✅ Connected to TokenPool contract 2025-10-21T16:59:13.700Z info: Remote pool 1: 0x5e8b0e5EAC57d73E7b93d85b8eA3fcaDa282868A → 0x0000000000000000000000005e8b0e5eac57d73e7b93d85b8ea3fcada282868a 2025-10-21T16:59:13.701Z info: === Rate Limiter Configuration === 2025-10-21T16:59:13.701Z info: Outbound enabled: false 2025-10-21T16:59:13.701Z info: Inbound enabled: false 2025-10-21T16:59:13.701Z info: === Executing applyChainUpdates() === 2025-10-21T16:59:15.699Z info: 📤 TX sent: 0xddcb3cae44fe84d05b47e1c5ee96e8290104005f4c01501416410c767542aa55 2025-10-21T16:59:15.699Z info: Waiting for 3 confirmations... 2025-10-21T16:59:51.435Z info: ✅ Chain update applied successfully on ethereumSepolia (3 confirmations)! ``` ### Mint Tokens In this step, you will use the `mintTokens` task to mint tokens on Avalanche Fuji for your Externally Owned Account (EOA). Since you assigned mint and burn privileges to your EOA when deploying the tokens in the first step, you can now mint tokens for testing purposes. This is to ensure that you have enough tokens in your EOA to perform cross-chain transfers in the next step. You will interact with the `BurnMintERC20` token contract, specifically calling the `mint()` function to mint tokens to your EOA. Below is an explanation of the parameters used during the minting process: | Parameter | Description | Default | Required | | ----------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | -------- | | `tokenaddress` | The address of the token for which tokens are being minted. | N/A | Yes | | `amount` | The amount of tokens to mint (in wei). | N/A | Yes | | `receiveraddress` | The address of the receiver of the minted tokens. If not provided, defaults to your EOA. | N/A | No | | `network` | The blockchain on which the minting process will be executed. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | Mint tokens to your EOA using the following command, replacing the token address with the one you deployed in the previous steps: 1. **Mint tokens on Avalanche Fuji:** ```bash npx hardhat mintTokens --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --amount 1000000000000000000000 --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T17:00:46.902Z info: 🪙 Minting 1000000000000000000000 BnMsak to 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca... 2025-10-21T17:00:48.879Z info: ⏳ Mint tx: 0xe2759da0ba03aa64bb488acd6518ebd5a927dd99e5df2116c9b6b324506a8a2a 2025-10-21T17:00:48.879Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:00:58.287Z info: ✅ Minted 1000000000000000000000 BnMsak to 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca 2025-10-21T17:00:58.287Z info: Current balance of 0x8c244f0b2164e6a3bed74ab429b0ebd661bb14ca: 1100000000000000000000 BnMsak ``` ### Transfer Tokens In this step, you will use the `transferTokens` task to transfer tokens from Avalanche Fuji to Ethereum Sepolia using CCIP. You have two options for paying CCIP fees: using LINK tokens or native gas tokens. You will interact with the `IRouterClient` contract, specifically calling the `ccipSend()` function to initiate the token transfer. Below is an explanation of the parameters used during the token transfer process: | Parameter | Description | Default | Required | | ------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | -------- | | `tokenaddress` | The address of the token being transferred. | N/A | Yes | | `amount` | The amount of tokens to transfer. | N/A | Yes | | `destinationchain` | The blockchain to which the tokens will be transferred. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | | `receiveraddress` | The address of the receiver on the destination blockchain. | N/A | Yes | | `fee` | The type of fee used for the transfer, either `LINK` or `native`. | `LINK` | No | | `network` | The blockchain on which the token transfer will be initiated. Examples include `avalancheFuji`, `ethereumSepolia`, `baseSepolia`, and `arbitrumSepolia`. | N/A | Yes | #### Pay fees in LINK Call the CCIP Router to transfer tokens from Avalanche Fuji to Ethereum Sepolia, paying the CCIP fees in LINK tokens. Replace the token address, amount, receiver address, and blockchain with the appropriate values: ```bash npx hardhat transferTokens --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --amount 100000000000000000000 --destinationchain ethereumSepolia --receiveraddress 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T17:02:33.667Z info: 🚀 Transferring 100000000000000000000 tokens via CCIP from avalancheFuji to ethereumSepolia... 2025-10-21T17:02:33.669Z info: Token: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T17:02:33.669Z info: Receiver: 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf 2025-10-21T17:02:33.669Z info: Fee token: LINK 2025-10-21T17:02:34.619Z info: 💰 Estimated fees: 12147121320763453 2025-10-21T17:02:34.877Z info: Approving 100000000000000000000 tokens for router 0xF694E193200268f9a4868e4Aa017A0118C9a8177 2025-10-21T17:02:36.962Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:02:42.129Z info: Approving 12147121320763453 LINK to router 2025-10-21T17:02:43.439Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:02:52.641Z info: 💰 Estimated CCIP fees: 12147121320763453 2025-10-21T17:02:52.642Z info: Sending CCIP message... 2025-10-21T17:02:53.934Z info: ⏳ CCIP message tx: 0x7b7bccaf0e29b3378a97ca0eb5c812b1fd54e97ab2c7072986abfbaf4844040a 2025-10-21T17:02:53.934Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:03:07.544Z info: ✅ CCIP message sent successfully 2025-10-21T17:03:07.544Z info: Transaction: 0x7b7bccaf0e29b3378a97ca0eb5c812b1fd54e97ab2c7072986abfbaf4844040a 2025-10-21T17:03:07.545Z info: Check status: https://ccip.chain.link/tx/0x7b7bccaf0e29b3378a97ca0eb5c812b1fd54e97ab2c7072986abfbaf4844040a 2025-10-21T17:03:07.545Z info: 📋 Transfer Summary: 2025-10-21T17:03:07.545Z info: Token: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T17:03:07.545Z info: Amount: 100000000000000000000 2025-10-21T17:03:07.545Z info: From: avalancheFuji 2025-10-21T17:03:07.545Z info: To: ethereumSepolia 2025-10-21T17:03:07.545Z info: Receiver: 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf 2025-10-21T17:03:07.545Z info: Fee paid in: LINK ``` #### Pay fees in native gas tokens Call the CCIP Router to transfer tokens from Avalanche Fuji to Ethereum Sepolia, paying the CCIP fees in native gas tokens. Replace the token address, amount, receiver address, and blockchain with the appropriate values: ```bash npx hardhat transferTokens --tokenaddress 0xb613B55897F07eAF430bF9a509498e55487305Ea --amount 100000000000000000000 --destinationchain ethereumSepolia --receiveraddress 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf --fee native --network avalancheFuji ``` Example output: ```bash ✅ Tasks loaded from /tasks/index.ts 2025-10-21T17:04:37.591Z info: 🚀 Transferring 100000000000000000000 tokens via CCIP from avalancheFuji to ethereumSepolia... 2025-10-21T17:04:37.592Z info: Token: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T17:04:37.592Z info: Receiver: 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf 2025-10-21T17:04:37.592Z info: Fee token: native 2025-10-21T17:04:38.579Z info: 💰 Estimated fees: 12327130238457656 2025-10-21T17:04:38.837Z info: Approving 100000000000000000000 tokens for router 0xF694E193200268f9a4868e4Aa017A0118C9a8177 2025-10-21T17:04:40.936Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:04:50.174Z info: 💰 Estimated CCIP fees: 12327130238457656 2025-10-21T17:04:50.174Z info: Sending CCIP message... 2025-10-21T17:04:51.485Z info: ⏳ CCIP message tx: 0xcc1e4371129d62e3bff8c2325f236298f64007c7fb6c12bf38b65b88c6791c75 2025-10-21T17:04:51.485Z info: Waiting for 2 confirmation(s)... 2025-10-21T17:05:00.696Z info: ✅ CCIP message sent successfully 2025-10-21T17:05:00.697Z info: Transaction: 0xcc1e4371129d62e3bff8c2325f236298f64007c7fb6c12bf38b65b88c6791c75 2025-10-21T17:05:00.697Z info: Check status: https://ccip.chain.link/tx/0xcc1e4371129d62e3bff8c2325f236298f64007c7fb6c12bf38b65b88c6791c75 2025-10-21T17:05:00.697Z info: 📋 Transfer Summary: 2025-10-21T17:05:00.697Z info: Token: 0xb613B55897F07eAF430bF9a509498e55487305Ea 2025-10-21T17:05:00.697Z info: Amount: 100000000000000000000 2025-10-21T17:05:00.697Z info: From: avalancheFuji 2025-10-21T17:05:00.697Z info: To: ethereumSepolia 2025-10-21T17:05:00.697Z info: Receiver: 0x27d7A69C878F9c8f51f4e53703abCE9bAcd2D9bf 2025-10-21T17:05:00.697Z info: Fee paid in: native ``` > **CAUTION: Educational Example Disclaimer** > > This page includes an educational example to use a Chainlink system, product, or service and is provided to > demonstrate how to interact with Chainlink's systems, products, and services to integrate them into your own. This > template is provided "AS IS" and "AS AVAILABLE" without warranties of any kind, it has not been audited, and it may be > missing key checks or error handling to make the usage of the system, product or service more clear. Do not use the > code in this example in a production environment without completing your own audits and application of best practices. > Neither Chainlink Labs, the Chainlink Foundation, nor Chainlink node operators are responsible for unintended outputs > that are generated due to errors in code.