Fhenix Orderbook

An orderbook implementation on the Fhenix blockchain, leveraging FHE for private balances and trade history.

The problem it solves

Private orderbooks have a few interesting features:

Private history of trades (visible only to user that completed trades)
Private balances of encrypted ERC20 tokens (base & trade tokens)
Absence of slippage thus impermanent loss
Absence of MEV

What was implemented

This project implements a private orderbook on the Fhenix blockchain leveraging FHE. We forked a publicy available repo and adapted that to use Fhenix's FHE Solidity library. The Solidity contract compiles and accepts buy orders and sell orders. We also incorporated the encrypted ERC20 template (FHERC20) into the contract.

We also deployed the contract on the Fhenix Frontier testnet (https://explorer.testnet.fhenix.zone/address/0xdE7f141Af8F0ccd82FC78AbF15116356dA98fD05).

Contracts

FHERC20: Encrypted ERC20, allowing for private balances and transfers
Orderbook: Private Orderbook, having features described previously.

Scripts

Buy orders (incomplete)
Sell orders (incomplete)

Plans for future implementation

We antecipate the following steps to bring this idea from hackathon project to a proper MVP:

Sanitize Orderbook.sol and confirm that no data leaks are present
Clean-up Hardhat usage (add hardhat-deploy for reproducible deployments)
Write tests