How to Migrate from Goerli to Sepolia

The Ethereum Foundation has announced that Goerli will be deprecated on January 2024. 

Ethereum has deprecated several testnets like Ropsten, Rinkeby, and Kovan, and Goerli will soon join the list. When a testnet is deprecated, it loses parity with the Ethereum Virtual Machine (EVM), making it unsafe and inaccurate for testing dapps and other Web3 projects.

As of The Merge, Ethereum and the recommended testnet, Sepolia have transitioned to Proof-of-Stake. Sepolia is continuously maintained by the Ethereum community, making it a suitable environment for testing Ethereum-based projects.  

What is the Sepolia Testnet?

Testing smart contracts is a critical part of the dapp development process. However, testing on the Ethereum mainnet is unnecessarily and prohibitively costly. Testnets like Sepolia exist to offer a cost-effective and smooth development experience.

Sepolia functions similar to Ethereum, allowing web3 developers to test their projects without spending real ETH tokens. With Sepolia, developers can confidently design, create, test, and monitor their project's performance before deploying it on the Ethereum mainnet.

Sepolia has a permissioned set of validators, and is relatively new meaning its state and history are small. These factors make running Sepolia nodes quick and easy for developers. 

How to Migrate from Goerli to Sepolia?

To migrate from Goerli to Sepolia testnet, create a new app in the Alchemy dashboard with the following details:

1. Chain: Ethereum
2. Network: Sepolia

To get the Sepolia RPC URL for your app, follow these steps:

1.  Click on the view key button
2.  Copy the HTTPS URL that appears

The new Sepolia RPC URL will look like this: https://eth-sepolia.g.alchemy.com/v2/

How to Get Sepolia ETH

Once you've created a new Sepolia RPC URL, the next step is to get Sepolia ETH.

You can get Sepolia ETH from Alchemy’s Sepolia faucet, which allows you to receive a small amount of Sepolia ETH to your EOA or smart contract wallet. 

Sepolia ETH is the currency used to complete transactions on the Sepolia testnet, similar to how ETH is used to pay gas for mainnet Ethereum transactions.

1. Go to the faucet: https://sepoliafaucet.com/
2. Enter your wallet address or ENS name in the provided box
3. Click on the “Send Me ETH” button to receive your Sepolia ETH

Open your Metamask wallet, go to the activity tab, and you can see all the transactions. 

In this example, 1 Sepolia ETH was deposited to the MetaMask wallet from the Sepolia faucet.

You can now start deploying and testing smart contracts on Sepolia testnet with your test ETH!

How to Access Sepolia Block Explorer

Web3 developers can use a Sepolia block explorer to access information such as the date and time of blocks, transaction fees, gas burned, and Sepolia testnet transaction data by looking up the transaction hash. For example, Etherscan’s Sepolia block explorer and Otterscan are two popular examples.

Three Considerations Before Migrating to Sepolia

If you're a dapp developer planning to migrate smart contracts from Goerli to Sepolia, there are several things to consider to ensure a safe transition: dependencies, deadlines, and testing.

1. Smart contract dependencies 

Review your smart contract dependencies on Goerli and make sure they are compatible with Sepolia's network. This can help you identify any potential issues that need to be addressed before migrating.

2. Impending Deadlines

Make sure to allocate the necessary resources and time to complete the migration before any impending deadlines. This can help you avoid any last-minute rushes or issues.

3. Testing and Verification

Determine the tests needed to validate a successful migration, such as verifying the compatibility of your smart contracts with Sepolia's network. This can help ensure that your dApp works as intended on Sepolia.

By considering these three areas, developers can complete their move from Goerli to Sepolia with confidence and ensure their decentralized application works on Sepolia.