Senior Java Software Engineer - €400 A Day - Remote

Job Title: Senior Java Developer (API & Legacy Modernisation) Location: Remote - Spain Rate: €400 per day Contract: 6-month rolling contract About the Role We're looking for an experienced Senior Java Developer to join a financial services programme focused on modernising legacy platforms and building high-quality APIs.This is a long-term contract opportunity for someone who thrives in complex enterprise environments and enjoys transforming legacy systems into scalable, modern architectures.Key Responsibilities Design and develop robust, secure, and scalable Java-based APIs and microservices Lead and contribute to legacy system modernisation initiatives Work closely with architects, product owners, and DevOps teams to deliver high-quality solutions Improve system performance, reliability, and maintainability Contribute to technical design, code reviews, and engineering best practices Support integration with internal and external financial systems Ensure solutions meet security, compliance, and regulatory standards Required Experience & Skills 10+ years of Java development experience Strong experience in API development (RESTful services, microservices architecture) Proven track record in legacy platform modernisation and refactoring Solid knowledge of: Spring / Spring Boot ecosystem Microservices and distributed systems Cloud platforms (AWS, Azure, or GCP) CI/CD and DevOps practices SQL and NoSQL databases Experience working in financial services / banking / fintech environments Strong understanding of security, scalability, and high-availability systems Excellent communication skills and ability to work in distributed teams Nice to Have Experience with containerisation (Docker, Kubernetes) Event-driven architectures (Kafka or similar) Experience with domain-driven design (DDD) Why Join?Competitive €400/day rate Fully remote role within Poland Long-term 6-month rolling contract Opportunity to work on high-impact modernisation projects in financial services

This is a long-term contract opportunity for someone who thrives in complex enterprise environments and enjoys transforming legacy systems into scalable, modern architectures. Key Responsibilities Design and develop robust, secure, and scalable Java-based APIs and microservices Lead and contribute to legacy system modernisation initiatives Work closely with architects, product owners, and DevOps teams to deliver high-quality solutions Improve system performance, reliability, and maintainability Contribute to technical design, code reviews, and engineering best practices Support integration with internal and external financial systems Ensure solutions meet security, compliance, and regulatory standards Required Experience & Skills 10+ years of Java development experience Strong experience in API development (RESTful services, microservices architecture) Proven track record in legacy platform modernisation and refactoring Solid knowledge of: Spring / Spring Boot ecosystem Microservices and distributed systems Cloud platforms (AWS, Azure, or GCP) CI/CD and DevOps practices SQL and NoSQL databases Experience working in financial services / banking / fintech environments Strong understanding of security, scalability, and high-availability systems Excellent communication skills and ability to work in distributed teams Nice to Have Experience with containerisation (Docker, Kubernetes) Event-driven architectures (Kafka or similar) Experience with domain-driven design (DDD) Why Join?

Competitive €400/day rate Fully remote role within Poland Long-term 6-month rolling contract Opportunity to work on high-impact modernisation projects in financial services