Blockchain Developer

Morgan McKinley; Greater London; On-site; GBP 80,000 - 110,000; Full time

Job summary

Morgan McKinley is partnering with a fast-growing Web3 protocol studio in London to recruit a Senior Web3 & Smart Contract Developer. You will architect secure, gas-efficient protocol contracts and oversee mainnet deployments across EVM and Solana ecosystems.

The role requires Solidity or Rust production experience, DeFi primitives, and collaboration with frontend engineers using Ethers.js, Viem, or Wagmi to connect contracts to apps while upholding rigorous security.

Qualifications

• 3+ years of production experience writing Solidity or Rust.
• Experience with DeFi primitives and security concepts.
• Proven track record deploying contracts on Ethereum, Arbitrum, Optimism, Base, or Solana mainnets.

Responsibilities

• Smart Contract Architecture: Design, write, test, and deploy secure, gas-optimized smart contracts in Solidity or Rust (EVM / Solana ecosystems).
• Protocol Security: Conduct rigorous unit testing (Foundry / Hardhat), perform formal verification, and work alongside external security auditing firms prior to mainnet launches.
• dApp Connectivity: Collaborate with frontend engineers to integrate smart contract state interactions via Ethers.js, Viem, or Wagmi.
• DeFi Logic Implementation: Implement decentralized financial mechanisms including yield vaults, staking rewards, liquidity pools, and governance (DAO) logic.

Skills

Solidity

Rust

Smart contract testing

Security

Tools

Foundry

Hardhat

Ethers.js

Viem

Wagmi

Job description

Senior Web3 & Smart Contract Developer (DeFi / Protocol)

Location: London, UK

Industry: Decentralized Finance (DeFi) & Web3 Protocol Studio

About the Opportunity

We are partnering with a fast-growing, venture-backed Web3 protocol studio expanding its core smart contract engineering team.

The team is building next-generation decentralized finance (DeFi) primitives, automated market maker (AMM) protocols, and cross-chain liquidity infrastructure. They are looking for a Senior Web3 / Smart Contract Developer to architect secure, gas-optimized protocol smart contracts and oversee production main net deployments.

Key Responsibilities

• Smart Contract Architecture: Design, write, test, and deploy secure, gas-optimized smart contracts in Solidity or Rust (EVM / Solana ecosystems).
• Protocol Security: Conduct rigorous unit testing (Foundry / Hardhat), perform formal verification, and work alongside external security auditing firms prior to mainnet launches.
• dApp Connectivity: Collaborate with frontend engineers to integrate smart contract state interactions via Ethers.js, Viem, or Wagmi.
• DeFi Logic Implementation: Implement decentralized financial mechanisms including yield vaults, staking rewards, liquidity pools, and governance (DAO) logic.

Key Requirements

• Languages: 3+ years of production experience writing Solidity or Rust (for Solana programs).
• Web3 Tooling: Deep familiarity with modern smart contract testing frameworks (Foundry, Hardhat).
• DeFi & Security Knowledge: Practical understanding of common DeFi standards (ERC-20, ERC-721, ERC-1155, ERC-4626) and security vectors (reentrancy, flash loans, front-running/MEV).
• Track Record: Verified smart contracts deployed on Ethereum, Arbitrum, Optimism, Base, or Solana mainnets.