Senior Java Backend Engineer – Web3 & Fintech (Remote US)

IntellectEU; Northern (KY); Hybrid; USD 120,000 - 180,000; Part time

Benefits offered by this job

International offices

Professional development opportunities

Job summary

IntellectEU is hiring a Senior Software Engineer to lead backend development for wallet operations, asset transfers, and blockchain integrations in a highly regulated fintech environment. You will own the delivery of core services, implement secure communications, and drive event-driven workflows at scale.

The role is remote within the US, initially 3 months with possible prolongation. You will leverage Java and Spring Boot, API-first design, and microservices to build scalable, observable

Qualifications

• 7+ years building production-grade backend systems in regulated environments.
• Experience with blockchain networks, smart contracts, or tokenization platforms.
• Deep expertise in Java and Spring Boot.
• API-first design, RESTful contracts, and microservices architecture.
• Strong concurrent, multi-threaded, and asynchronous programming.
• Proven delivery of highly available, distributed applications.
• Experience with Apache Kafka and event-driven systems.
• Understanding of CI/CD, DevSecOps, and automated security controls.
• Experience with OpenTelemetry and distributed tracing.
• Ability to produce API specs and runbooks.

Responsibilities

• Own backend services delivery with fault tolerance, security, and scalability.
• Build API-first services integrating blockchain networks and internal systems.
• Implement secure service communications and zero-trust principles.
• Operate event-driven systems using Apache Kafka and asynchronous patterns.
• Create highly available, scalable, multi-threaded services.
• Integrate Web3 SDKs for on-chain interactions and signing.
• Instrument with logging, tracing, and observability tools.
• Maintain high test coverage in CI/CD pipelines.
• Produce API specs and operational runbooks.

Skills

Java

Spring Boot

RESTful API design

Concurrent programming

Distributed systems

CI/CD

Security controls

OpenTelemetry

APIs & microservices

Web3 libraries

Tools

Apache Kafka

Web3.js / Ethers.js

RESTful tooling

API specifications

Job description

IntellectEU is hiring a Senior Software Engineer to lead backend development for wallet operations, asset transfers, and blockchain integrations in a highly regulated fintech environment. You will own the delivery of core services, implement secure communications, and drive event-driven workflows at scale.

The role is remote within the US, initially 3 months with possible prolongation. You will leverage Java and Spring Boot, API-first design, and microservices to build scalable, observable