Blockchain Web3 Engineer
Cleo Consulting
New York, United States of America
yesterday
Role details
Contract type
Permanent contract Employment type
Full-time (> 32 hours) Working hours
Regular working hours Languages
EnglishJob location
New York, United States of America
Tech stack
Node.js
Quorum
Blockchain
Management of Software Versions
Delivery Pipeline
Backend
Hyperledger
Performance Monitor
Ethereum
Solidity
Web3.js
Job description
- Design, develop, and maintain smart contracts (Solidity/Vyper or relevant stack) aligned to product and security requirements.
- Build backend/Web3 components for contract interaction:
- Transaction orchestration, signature flows, nonce management, gas strategies
- Web3 SDK integrations
- Develop and manage contract deployment pipelines, including ABI/versioning, migrations, upgrade strategies (proxy patterns), and release coordination.
- Implement secure patterns for contracts:
- Support smart contract testing:
- Node Operations & Infrastructure
- Deploy, configure, and operate blockchain nodes and supporting infrastructure:
- Full nodes/archival nodes, RPC endpoints, validator nodes (as applicable)
- Manage node upgrades, chain configuration changes, and incident response for production networks.
- Implement operational tooling for:
- Node health checks, RPC performance monitoring, log aggregation, and alerting
- Handle blockchain-specific reliability concerns:
- Re-org handling, finality considerations, peer connectivity, RPC failover, rate limiting
Requirements
- Core Web3 / Blockchain Skills (Must-Have)
- Strong understanding of blockchain fundamentals:
- transactions, blocks, gas/fees, wallets/keys, RPC, finality, consensus basics
- Hands-on experience with smart contracts:
- Solidity (preferred) and development tooling (Hardhat/Foundry/Truffle/Remix)
- Experience working with EVM-based chains (Ethereum/Polygon/Arbitrum/Optimism/BSC)
- or enterprise chains (Hyperledger Fabric/Corda/Quorum) depending on project