#Migrating from Waffle

This page explains how to migrate from Waffle to Hardhat Chai Matchers, and the advantages of doing it.

# How to migrate

The @nomicfoundation/hardhat-chai-matchers plugin is meant to be a drop-in replacement for the @nomiclabs/hardhat-waffle plugin. To migrate, follow these instructions:

Uninstall the @nomiclabs/hardhat-waffle and ethereum-waffle packages:

npm

yarn

npm uninstall @nomiclabs/hardhat-waffle ethereum-waffle

yarn remove @nomiclabs/hardhat-waffle ethereum-waffle

Then install the Hardhat Chai Matchers plugin:

npm

yarn

npm install @nomicfoundation/hardhat-chai-matchers

yarn add @nomicfoundation/hardhat-chai-matchers

In your Hardhat config, import the Hardhat Chai Matchers plugin and remove the hardhat-waffle one:

TypeScript

JavaScript

- import "@nomiclabs/hardhat-waffle";
+ import "@nomicfoundation/hardhat-chai-matchers";

- require("@nomiclabs/hardhat-waffle");
+ require("@nomicfoundation/hardhat-chai-matchers");

If you were not importing the @nomiclabs/hardhat-ethers plugin explicitly (because the Hardhat Waffle plugin already imported it), then add it to your config:
TypeScript
JavaScript
```
import "@nomiclabs/hardhat-ethers";
```
```
require("@nomiclabs/hardhat-ethers");
```

# Why migrate?

The Hardhat Chai Matchers are compatible with Waffle's API and offer several advantages:

More features: the Hardhat Chai Matchers include new matchers, like .revertedWithCustomError and .revertedWithPanic, which let you perform better assertions of a transaction's revert reason.
Support for native BigInts: Besides numbers and ethers’s BigNumbers, you can also use JavaScript's native BigInts in your assertions, which means being able to do things like expect(await token.totalSupply()).to.equal(10n**18n) instead of expect(await token.totalSupply()).to.equal(ethers.BigNumber.from("1000000000000000000")).
More reliable: Several problems and minor bugs in Waffle's matchers are fixed in the Hardhat Chai Matchers.