Tutorial

Quick Start Guide

Build your first FHE-enabled smart contract in four steps.

What you'll learn

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Setting up your dev environment with Maze FHE libraries

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Converting standard Solidity types to encrypted types

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Using FHE operations for arithmetic on encrypted data

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Implementing access control for decryption permissions

Environment Setup

Install Node.js, Hardhat, and Maze FHE dependencies

Write Basic Contract

Start with a simple Solidity contract

Convert to Maze FHE

Transform your contract to support FHE operations

Test & Deploy

Test locally and deploy to testnet

Environment Setup

Ensure you have Node.js v18+, npm or yarn, and basic Solidity knowledge.

Terminalbash

npm install --save-dev hardhat
npx hardhat init

# Download MAZE FHE library
mkdir -p maze-solidity/{lib,config}
curl -sL https://mazedapp.org/maze-solidity/lib/FHE.sol -o maze-solidity/lib/FHE.sol
curl -sL https://mazedapp.org/maze-solidity/lib/MazeACL.sol -o maze-solidity/lib/MazeACL.sol
curl -sL https://mazedapp.org/maze-solidity/config/MazeConfig.sol -o maze-solidity/config/MazeConfig.sol

Write a Basic Contract

Start with a simple Solidity counter contract that we’ll convert to FHE.

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pragma solidity ^0.8.0;
 
contract Counter {
    uint32 private _count;
    
    function getCount() public view returns (uint32) {
        return _count;
    }
    
    function increment(uint32 value) public {
        _count += value;
    }
}

Convert to Maze FHE

Here’s the same contract modified to use encrypted values:

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pragma solidity ^0.8.0;
 
import {FHE, euint32, externalEuint32} from "@maze/solidity/lib/FHE.sol";
import {MazeEthereumConfig} from "@maze/solidity/config/MazeConfig.sol";
 
contract FHECounter is MazeEthereumConfig {
    euint32 private _count;
    
    function getCount() public view returns (euint32) {
        return _count;
    }
    
    function increment(externalEuint32 calldata inputEuint32, bytes calldata inputProof) public {
        euint32 evalue = FHE.fromExternal(inputEuint32, inputProof);
        _count = FHE.add(_count, evalue);
        FHE.allowThis(_count);
        FHE.allow(_count, msg.sender);
    }
}

Key Changes

▸Import FHE library: Access encrypted types and operations

▸uint32 → euint32: Standard type becomes encrypted

▸FHE.fromExternal(): Convert external encrypted input with ZK proof

▸FHE.add(): Perform addition on encrypted values

▸FHE.allow(): Grant decryption permission to specific addresses

Test & Deploy

Terminalbash

npx hardhat test
npx hardhat run scripts/deploy.js --network sepolia

Important

▸Test on testnets before mainnet deployment
▸Ensure you have testnet ETH for gas fees
▸Verify contract addresses after deployment
▸Use MAZE Playground to test contracts interactively

Next Steps

Continue your Maze FHE journey:

View Detailed Example Try Interactive Playground