hardhat-zksync-vyper

The @matterlabs/hardhat-zksync-vyper plugin provides an interface for compiling Vyper smart contracts before deploying them to zkSync Era.

Learn more about the latest updates in the changelog.

Prerequisites

• Download and install Node.
• Download and install nvm to change the running Node version to latest use command nvm use --lts.
• Use the yarn or npm package manager. We recommend using yarn. To install yarn, follow the Yarn installation guide.
• A wallet with sufficient Göerli ETH on Ethereum and zkSync Era Testnet to pay for deploying smart contracts.
  • You can get Göerli ETH from the following faucets:
    • Chainstack Goerli faucet
    • Alchemy Goerli faucet
    • Paradigm Goerli faucet
    • Proof of work faucet
  • Get testnet ETH on zkSync Era from the zkSync portal.
• You know how to get your private key from your MetaMask wallet.

Local zkSync Testing with zksync-cli

Skip the hassle for test ETH by using zksync-cli for local testing. Simply execute npx zksync-cli dev start to initialize a local zkSync development environment, which includes local Ethereum and zkSync nodes. This method allows you to test contracts without requesting external testnet funds. Explore more in the zksync-cli documentation.

Set up

1. Scaffold a new project

Use the zkSync Era cli to set up a project.

npx zksync-cli@latest create-project greeter-vyper-example --template hardhat_vyper
cd greeter-vyper-example

2. Install the libraries

The plugin is used with @nomiclabs/hardhat-vyper.

yarn add -D @matterlabs/hardhat-zksync-vyper @nomiclabs/hardhat-vyper

npm i -D @matterlabs/hardhat-zksync-vyper @nomiclabs/hardhat-vyper

3. Update the hardhat.config.ts file

import { HardhatUserConfig } from "hardhat/config";

import "@nomiclabs/hardhat-vyper";
import "@matterlabs/hardhat-zksync-vyper";
import "@matterlabs/hardhat-zksync-deploy";

const config: HardhatUserConfig = {
  zkvyper: {
    version: "latest", // Uses latest available in https://github.com/matter-labs/zkvyper-bin/
    settings: {
      // compilerPath: "zkvyper", // optional field with the path to the `zkvyper` binary.
      libraries: {}, // optional. References to non-inlinable libraries
    },
  },
  defaultNetwork: "zkSyncTestnet",
  networks: {
    hardhat: {
      zksync: true, // enables zksync in hardhat local network
    },
    zkSyncTestnet: {
      url: "https://testnet.era.zksync.dev",
      ethNetwork: "goerli",
      zksync: true,
    },
  },
  // Currently only Vyper v0.3.3 and v0.3.9 versions are supported.
  vyper: {
    version: "0.3.3",
  },
};

export default config;

Configuration

zero-config

hardhat-zksync-vyper v0.2.0 introduced a default configuration so all parameters are optional.

Any configuration parameters should be added inside a zkvyper property in the hardhat.config.ts file:

• version: The zkvyper compiler version. Default value is latest. Find the latest compiler versions in the zkvyper repo.
• compilerSource: Indicates the compiler source and can be either binary. (A docker option is no longer recommended). If there is no previous installation, the plugin automatically downloads one.
• compilerPath: Optional field with the path to the zkvyper binary. By default, the binary in $PATH is used.
• libraries: Define any non-inlinable libraries your contracts use as dependencies here. Learn more about compiling libraries.

4. Create Vyper contract

The zkSync Era cli generates a contracts folder which includes a Greeter.sol contract.

• Delete Greeter.sol from the contracts/ directory.
• Add the equivalent Greeter.vy Vyper contract:

# @version ^0.3.3
# vim: ft=python

owner: public(address)
greeting: public(String[100])

# __init__ is not invoked when deployed from create_forwarder_to
@external
def __init__(greeting: String[64]):
  self.owner = msg.sender
  self.greeting = greeting

# Invoke once after create_forwarder_to
@external
def setup(_greeting: String[100]):
  assert self.owner == ZERO_ADDRESS, "owner != zero address"
  self.owner = msg.sender
  self.greeting = _greeting

@external
@view
def greet() -> String[100]:
    return self.greeting

5. Compile the contract

yarn hardhat compile

npx hardhat compile

6. Create deployment script

First update the use-greeter.ts script, supplied by the CLI in the deploy/ directory.

Alter this line:

// Load contract artifact. Ensure to compile first!
import * as ContractArtifact from "../artifacts-zk/contracts/Greeter.sol/Greeter.json";

To aim at our Vyper contract:

// Load contract artifact. Ensure to compile first!
import * as ContractArtifact from "../artifacts-zk/contracts/Greeter.vy/Greeter.json";

7. Add private key to environment variables

Remove example from the .env.example file and add your private key to <WALLET-PRIVATE-KEY>.

8. Deploy the contract

yarn hardhat deploy-zksync --script deploy-greeter.ts

9. Output

You should see something like this:

Running deploy function for the Greeter contract
The deployment is projected to cost 0.000135806 ETH
constructor args:0x000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000094869207468657265210000000000000000000000000000000000000000000000
Greeter was deployed to 0x7CDF8A4334fafE21B8dCCe70487d6CBC00183c0d