Foundry

Have you ever wondered how devs deploy contracts to addresses starting with 0x42069… or 0x0000…? Or how the Seaport contract address has 14 leading zeros?

Using Foundry, it’s much easier than you’d think. I’ll break it down in this guide:

To start, go to your foundry.toml file and ensure you have write permissions enabled in your fs_permissions config (at the bottom)

Protocol Engineer @ OpenSea. Creator of Net + the Together Collective NFT studio. Nothing I say/share is financial advice. netprotocol.app

Next, create a new script, import the contract (ex. WillieNet) you want to deploy to a deterministic address, and write the following code to read your contract’s creation code and store that in a file

Then, run the script: `forge script script/GetWillieNetCreationCode.s.sol`

The above script will output the creation code of your contract to the `script/out/creation-code.bin` path

Next, we'll find (mine) a salt, using that file, that allows us to deploy a contract to an address with our desired prefix

Run the following command to mine the salt

In this example, we run this command to find a salt that would yield a deployment of this contract to an address starting with 0x42069. Copy the salt value (0x85…) to your clipboard

Create a new solidity script to deploy your contract and for the `salt` variable, paste in the value from the previous step

Run your script but don’t broadcast the transaction! We first want to ensure that the logged “Actual address” matches the address we expect

Looks like the address starts with the prefix (42069) that we expect and matches the address generated by `cast create2` in the earlier salt mining step

Great! You can now deploy your contract to EVM-based chains and it should be deployed to the 0x42069... address!

You may notice that for long prefixes, the `cast create2` command seems to run indefinitely. That’s because, the longer the prefix, the more time it’ll take to find a salt that results in an address with that prefix

If you are looking for a very long prefix (ex. 14 leading zeros, as in the Seaport case), you should look into create2crunch by @0age which allows you to parallelize salt mining using a GPU

If you are looking for a very long prefix (ex. 14 leading zeros, as in the Seaport case), you should look into create2crunch by @0age which allows you to parallelize salt mining using a GPU https://github.com/0age/create2crunch

This guide was inspired by this article about deterministic deployments using foundry https://2ad.com/deterministic-deployment.html

Once WillieNet is open-source, I will share that repo which contains all the scripts discussed here

Disclaimer: there may be additional nuances depending on your use-case that affect the behavior of the steps in this guide and I do not take any responsibility for any problems/issues you encounter

Use this guide at your own risk

If you found this guide helpful, feel free to recast

If you found this guide helpful, feel free to recast https://warpcast.com/aspyn/0xd2de58a3