Blockchain Developer (Java)
IntellectEU3 months ago
Remote, United StatesSenior
Responsibilities
- Build and operationalize fault-tolerant, secure, scalable backend services for wallet operations, asset transfers, transaction orchestration, blockchain integrations, and event-driven workflows.
- Design API-first services integrating blockchain networks, third-party providers, and internal systems with strong consistency guarantees.
- Implement secure service communications using cryptographic signatures, key management, and zero-trust architecture principles.
- Build event-driven systems with Apache Kafka and asynchronous messaging patterns.
- Implement highly available, strongly consistent, horizontally scalable services and concurrent, asynchronous, multi-threaded processing.
- Integrate Web3 SDKs and libraries for on-chain interactions, transaction signing, and state monitoring.
- Implement structured logging, distributed tracing, metrics, and OpenTelemetry instrumentation.
- Maintain automated unit, integration, and functional test coverage within CI/CD pipelines.
- Produce technical documentation, API specifications, and operational runbooks.
Requirements
- At least 7 years of software engineering experience building and operating production-grade backend systems in regulated financial or enterprise environments.
- Experience with blockchain networks, smart contracts, consensus mechanisms, crypto integration, or tokenization platforms.
- Extensive hands-on proficiency in Java and Spring Boot, with comfort working across polyglot stacks.
- Deep expertise in API-first design, RESTful service contracts, microservices architecture, concurrency, multi-threaded programming, and asynchronous programming models.
- Proven experience delivering highly available, strongly consistent, distributed applications and event-driven solutions using Apache Kafka.
- Strong understanding of CI/CD, DevSecOps, secure SDLC, and automated security controls.
- Hands-on experience with OpenTelemetry, distributed tracing, and observability platforms.
- Strong technical writing skills and experience producing API specifications and operational runbooks.
- Experience using Web3 libraries and SDKs such as Web3.js and Ethers.js.
- Preferred experience with TypeScript, Node.js, NestJS, Ethereum, Bitcoin, Solana, XRPL, MPC, HSMs, enterprise key management systems, zero-trust security architecture, tokenization, stablecoins, settlement systems, digital asset operations, or open-source blockchain projects.
Benefits
- Remote work from the US.
- B2B cooperation with a 3-month initial contract and possibility of extension.
- International experience at a stable company operating for over 15 years with offices across Europe and New York.
- Passionate, innovative, casual, positive, and open work environment.
- Personal and professional development opportunities and the chance to influence financial technology.
- Applicant data is processed for recruitment purposes, may be transferred internationally with safeguards, and is retained for up to 24 months unless otherwise required or deleted earlier.
Tech Stack
Categories
About IntellectEU
IntellectEU is a privately held fintech engineering firm that builds and integrates systems for banks and capital markets, from SWIFT modernization to AI and blockchain/DLT solutions. The company delivers consulting, custom development, and managed integration for payments, financial messaging, and tokenization use cases. Founded in 2006 and headquartered in Antwerp, Belgium, it is a long-standing SWIFT partner focused on bridging legacy platforms with modern financial networks.