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👷 Fhenix Hardhat Plugin

Fhenix Hardhat Plugin is designed to extend your Hardhat environment with additional capabilities focused on Fhenix. It integrates seamlessly with your Hardhat projects to provide a local Fhenix environment, including customized network configuration and utilities for managing funds and permits within your blockchain applications.


  • Local Fhenix Environment: Automatically sets up a local Fhenix network configuration within Hardhat, allowing for easy deployment and interaction with Fhenix contracts.
  • Faucet Integration: Enables developers to easily obtain funds for testing purposes through a simple API call to a local faucet.
  • Permit Management: Simplifies the process of creating and storing permit signatures required for transactions, reducing the complexity of interacting with contracts that require permissions.

If you want to see a full example in action, check out our Hardhat Example Template!


To use FhenixJS in your Hardhat project, first install the plugin via npm (or your favorite package manager):

pnpm install fhenix-hardhat-plugin

If you wish to run your own local dev environment, please install the fhenix-hardhat-docker plugin as well.

pnpm install fhenix-hardhat-docker


After installation, import the plugin in your Hardhat configuration file (e.g., hardhat.config.js):

// if using the docker plugin

or if you are using TypeScript, in your hardhat.config.ts:

import "fhenix-hardhat-plugin";
// if using the docker plugin
import "fhenix-hardhat-docker";


Network Configuration

The plugin automatically adds a localfhenix network configuration to your Hardhat project. This configuration is designed for local development and includes settings such as gas estimates, accounts, and the local network URL.

To target this network, simply add --network localfhenix to your hardhat commands, or set it as the default.

If you want to use Fhenix Frontier (or a custom Fhenix network), you can add a new network configuration to your hardhat.config.js file:

const config: HardhatUserConfig = {
networks: {
fhenix: {
url: "",
chainId: 412346,
accounts: mnemonic,

export default config;

Using FhenixJS from Hardhat Runtime Environment

After importing fhenix-hardhat-plugin hardhat will automatically extend the Hardhat Runtime Environment (HRE) with a fhenixjs object, providing access to Fhenix-specific functionality:

  • Use the fhenixjs object directly to encrypt, unseal or manage permits.
  • getFunds(address: string): Request funds from the local faucet for the specified address.
  • createPermit(contractAddress: string, provider?: SupportedProvider): Create and store a permit for interacting with a contract.


Local Dev Environment

To set up a localfhenix instance, simply import fhenix-hardhat-docker. This will add two new hardhat tasks:

  • localfhenix:start To start a local dev environment using docker. By default, the instance will listen for rpc connections on port 42069
  • localfhenix:stop Stops the docker container

To start the container:

pnpm hardhat localfhenix:start

If starting the instance was successful, you should see the message: Started LocalFhenix successfully at

To stop the running container:

pnpm hardhat localfhenix:stop

Which will result in Successfully shut down LocalFhenix

Requesting Funds

To request funds from the local faucet for an address, use the getFunds method:

await hre.fhenixjs.getFunds("your_wallet_address");


const encyrptedAmount = await fhenixjs.encrypt_uint32(15);

Creating a Permit

To create a permit for a contract, use the createPermit method:

const permit = await hre.fhenixjs.createPermit("contract_address");


For issues, suggestions, or contributions, please open an issue or pull request in the Hardhat Fhenix Plugin GitHub repository.