Blockchain Developer

Blockchain DeveloperLocation: New York, NY / Jersey City, NJPosition Type: Fulltime7+ Years of expKey ResponsibilitiesDesign, develop, and deploy Web3 components and integrations for a Digital Asset Platform, including smart contracts, on-chain event listeners, wallet integrations, and blockchain protocol connectorsBuild and maintain backend services that interface with public and permissioned blockchain networks (e.g., Ethereum, Hyperledger Besu, Corda, or equivalent)Develop, test, and audit smart contracts written in Solidity or equivalent languages, ensuring security, correctness, and gas efficiencyIntegrate Web3 libraries and SDKs (e.g., Web3J, Web3JS, Ethers.js, Viem) into enterprise Java and/or Node.js backend servicesImplement asynchronous, event-driven architectures to handle on-chain events, transaction lifecycle management, and blockchain state synchronizationCollaborate with architects and senior engineers to contribute to the design of scalable, secure, and resilient Web3 infrastructureParticipate in code reviews, providing and receiving constructive technical feedback to maintain high engineering standardsSupport the integration of digital asset custody solutions, tokenization frameworks, and DeFi/TradFi bridging componentsContribute to technical documentation, including smart contract specifications, integration guides, and architecture notesStay current with the rapidly evolving Web3 ecosystem — tracking protocol upgrades, new token standards, Layer 2 solutions, and emerging tooling relevant to institutional use casesWork within Agile/Scrum frameworks, participating in sprint planning, stand-ups, and retrospectives within a distributed global teamHelp identify and resolve technical issues across the Web3 stack, escalating where appropriate to ensure delivery quality and timelinesQualifications / ExperienceBachelor's degree in Computer Science, Engineering, or a related discipline; MS is a plus8+ years of overall software engineering experience, with a strong backend development foundation2 to 4 years of hands-on experience in Web3 and blockchain application development, including smart contract development and blockchain protocol integration3 to 5 years of experience with backend development using Java/Spring, Node.js, or equivalent enterprise frameworksProficiency in Solidity smart contract development, including testing frameworks (Hardhat, Foundry, Truffle) and security best practicesHands-on experience with Web3 libraries such as Web3J, Web3JS, Ethers.js, or ViemSolid understanding of blockchain fundamentals — consensus mechanisms, transaction lifecycle, gas models, wallet infrastructure, and key managementExperience with token standards (ERC-20, ERC-721, ERC-1155, ERC-3525, or equivalent) and tokenization patternsFamiliarity with permissioned blockchain networks (Hyperledger Besu, Fabric, Corda, or R3) is a strong plusExperience with asynchronous programming, event-driven systems, and message queuing (Kafka, RabbitMQ, or equivalent)Familiarity with DevOps practices, containerization (Docker, Kubernetes), and CI/CD pipelinesUnderstanding of cryptographic concepts — digital signatures, hashing, PKI, and secure key management — as applied to blockchain systemsExposure to Layer 2 scaling solutions (Polygon, Optimism, zkSync, etc.) and cross-chain interoperability protocols is a plusExperience in financial services or regulated industries is a plusFamiliarity with Agile/Scrum methodologies and distributed team collaboration toolsCompetencies / SkillsWeb3 Engineering Depth: Strong command of the Web3 technology stack — from smart contract development to on-chain/off-chain integration patterns and blockchain node interactionBackend Engineering Fundamentals: Solid grounding in enterprise software engineering — API design, microservices, data structures, algorithms, and design patternsSecurity Mindset: Awareness of common smart contract vulnerabilities (reentrancy, front-running, integer overflow, etc.) and best practices for secure on-chain developmentCuriosity & Adaptability: Genuine enthusiasm for the Web3 ecosystem and the ability to rapidly learn and apply new protocols, standards, and toolingCollaborative Spirit: Strong team player who communicates clearly and constructively with engineers, architects, and non-technical stakeholdersDelivery Orientation: Ability to manage personal delivery commitments, prioritize effectively, and produce high-quality output within sprint cyclesAttention to Detail: Rigorous approach to testing, code quality, and documentation — particularly important given the immutable nature of on-chain deploymentsTooling Proficiency: Working knowledge of engineering tools including Git, Jira, Jenkins, Hardhat/Foundry, Docker, Helm, and observability platforms