Serokell is hiring a Senior Smart Contract Engineer to design, build and launch secure blockchain products and wallet-connected user experiences across networks like Ethereum, Arbitrum, Optimism, Base and Polygon.
Responsibilities:
- Design, develop, test and deploy secure smart contracts.
- Build and maintain wallet integration flows (connection, signing, network switching, error handling).
- Collaborate with frontend and backend teams to integrate contracts into products.
- Improve contract architecture for security, scalability, maintainability and gas efficiency.
- Write unit, integration and end-to-end tests; support deployment, verification, monitoring and upgrades.
- Participate in code reviews and define technical requirements with product teams.
Requirements:
- 5+ years of professional experience as a Smart Contract / Blockchain Engineer.
- Strong proficiency in Solidity and EVM-based smart contract development.
- Experience with Hardhat, Foundry or Truffle.
- Experience with wallet integration libraries (ethers.js, web3.js, wagmi, viem) and wallets (MetaMask, WalletConnect, Coinbase Wallet).
- Strong understanding of gas optimization, transaction lifecycle, upgrade patterns, token standards (ERC-20, ERC-721, ERC-1155) and event indexing.
- Experience with smart contract testing, auditing processes and security best practices.
Preferred:
- Experience building DeFi, NFT, staking, DAO, payment or wallet-related products.
- Experience with Layer-2 networks (Arbitrum, Optimism, Base, Polygon, zkSync), account abstraction, smart wallets, multisig or gasless transactions.
- Familiarity with The Graph, blockchain indexers, on-chain analytics and frontend frameworks like React / Next.js.
Benefits / Conditions:
- Fully remote, work from anywhere in the world.
- Competitive compensation and flexible working hours.
- Collaborative, experienced engineering team and opportunity to work on innovative Web3 products.