Senior Java Developer
Design, build and maintain the backend services underneath the platform — the APIs the products are built on, and the integrations out to third-party financial and blockchain systems. Part of the work is reviewing and hardening code an AI wrote, which is named here because it is genuinely part of the day.
Sofia · office-first, Fridays from home
What you would do
- Design, develop and maintain scalable backend services in Java
- Build and optimise REST APIs, and integrate third-party financial and blockchain services
- Review, validate and improve AI-generated code without lowering the standard it is held to
- Take part in architecture discussions and technical decisions
- Write clean, maintainable, well-tested code
- Troubleshoot production issues and keep improving performance
- Mentor junior developers and spread practice across the team
What you would bring
- Software you have built in fintech
- Five years or more of professional Java
- Java and Spring Boot in depth
- REST APIs, and external services integrated into them
- Relational and NoSQL databases
- Git and modern development workflow
- The judgement to evaluate and safely use code an AI produced
What would help
- AI coding tools — Cursor, GitHub Copilot, Claude Code, Aider
- LLMs, prompt engineering, agents, LangChain
- Docker, Kubernetes, microservices, CI/CD
- Blockchain, smart contracts or crypto protocols
- Payments or financial systems specifically
What comes with it
- Competitive salary
- Twenty-five days of paid annual leave
- Ten paid study days a year if you are still studying, where the statutory entitlement is unpaid
- Private health insurance on the Lux package
- A sports card, with a choice of two schemes
- A modern office one minute from the metro
- Office-first, with Fridays worked from home