Senior SmartContract Developer

About the role: As a Senior Smart Contract Developer / Blockchain Engineer with expertise in enterprise blockchain platforms, you will collaborate with our client’s blockchain and cloud infrastructure teams, architects, product owners, and external partners in multi-organisation blockchain networks. You will be responsible for designing, developing, testing, and deploying smart contracts and blockchain solutions for enterprise environments. Job Details: Location: London Duration: 04/12/2026 Days on site: 2 days/ Week Roles and Responsibilities: • Design, develop, test, and deploy smart contracts for enterprise blockchain platforms (Ethereum, Go Quorum, Hyperledger Besu, Corda). • Implement asset tokenization, on-chain/off-chain data models, and blockchain transaction workflows. • Develop and integrate RESTful APIs and microservices (Node.js / Java) to interact with smart contracts. • Ensure security, performance, and scalability of smart contracts and blockchain applications. • Collaborate with architects, product owners, and external partners in multi-organization blockchain networks. • Lead or mentor development teams, enforcing coding standards, testing, and best practices. • Work closely with cloud infrastructure teams to deploy blockchain solutions using Azure/AWS services. • Support POCs, innovation initiatives, and exploration of Layer 2 scaling solutions. • Participate in design reviews, audits, and governance processes related to blockchain systems. Other stuff we’re potentially looking for: • 8+ years of experience in software engineering with strong blockchain focus. • Hands-on experience with Solidity smart contract development. • Strong understanding of Ethereum-compatible platforms (Go Quorum, Hyperledger Besu). • Experience with enterprise blockchain frameworks such as R3 Corda and Ripple. • Proficiency in Node.js, TypeScript, and/or Java (Spring Boot). • Strong knowledge of microservices architecture and asynchronous processing patterns. • Experience designing on-chain vs off-chain data models. • Familiarity with REST APIs, event-driven systems, and message queues. • Solid understanding of blockchain security concepts (permissions, key management, transaction integrity). What’s in it for you? • This is a contract role until Dec 2026. • A daily rate, in-scope IR35, of £535 (via a Hays Approved Umbrella Company). • This role provides a hybrid working access in London (2 days onsite). Next Steps: Once you’ve applied, one of our friendly recruitment consultants will give you a call and talk you through the screening process. If your application is successful, you’ll be involved in a live virtual interview with one of our client’s hiring managers to get to know you better. We look forward to speaking to you!