We're hiring: Senior Java Developers i Gaming / Sportsbook / Online Casino | Senior Java Backend | Kafka or Rabbit MQ | Hybrid in Madrid. Salary: From €65k to €70k gross/year (DEO) + 10% bonus Ideally with payments, i Gaming/Gambling or Fin Tech experience (integrations and payments gateways) My client in the i Gaming industry (online Casino and Sportbooks) is looking for a Senior Java developer, to work hybird from Madrid (3 days in the office, 2 days remote). Role Overview We are seeking a Senior backend engineer to build and scale core platform services in a distributed, event-driven environment. The role focuses on designing reliable, high-performance systems, including APIs, asynchronous workflows, and distributed transactions. You will ensure system resilience, data integrity, and observability while contributing to testing, security, and CI/CD practices. Collaboration with engineering, Dev Ops, and compliance teams is key to shaping architecture and maintaining high standards across performance, scalability, and reliability. Skills & Experience 8+ years of experience with Java, 5+ of experience with Spring, Springboot and Microservices 1+ years of experience within the payments, i Gaming or Fin Tech industry 1+ years of experience with platforms integrations and payments gateway. 2+ years of experience with Kafka or Rabbit MQ. 1+ year of experience with Redis (cashing system) Key Responsibilities Develop and maintain core backend services (identity, transactions, data integrity) within an event-driven architecture. Build reliable, asynchronous workflows and high-performance APIs with proper versioning and consistency guarantees. Implement distributed transactions, concurrency controls, and resilience patterns to ensure system stability and correctness. Manage database evolution, security (auth/authz), testing, and observability across services. Contribute to internal tools, CI/CD, infrastructure, and leverage AI tools to enhance development efficiency.