Senior Java Backend Engineer (Spring Boot, Quarkus)

About the role

We are seeking a Backend Developer with strong expertise in Java (21+), Spring Boot, and Quarkus to build and optimise high‑performance, scalable, and secure backend services. The ideal candidate will have hands‑on experience with Keycloak (IAM), SQL/NoSQL databases, troubleshooting, and performance optimisation in distributed micro‑services environments.

Key responsibilities

• Design, develop and maintain scalable micro‑services using Spring Boot and Quarkus.
• Integrate and manage Keycloak for authentication, authorisation and RBAC.
• Optimise and query SQL/NoSQL databases efficiently.
• Implement secure, stateless APIs with JWT‑based authentication.
• Conduct troubleshooting and root‑cause analysis for production issues.
• Collaborate with DevOps/SRE teams to ensure scalable deployment on OpenShift.

Required profile

• 8‑10 years of professional experience in backend development.
• Strong proficiency in Java 17+ (preferably 21) with hands‑on Spring Boot and Quarkus.
• Solid understanding of Keycloak, OAuth2, OIDC and JWT.
• Experience with relational (PostgreSQL, MySQL) and NoSQL (MongoDB, Redis, Cassandra) databases.
• Deep knowledge of micro‑services architecture, API gateways and distributed systems.
• Proven debugging, troubleshooting and performance optimisation skills (DB tuning, caching, async processing, profiling).

Required skills

• Java 21
• Spring Boot
• Quarkus
• Keycloak
• OAuth2 / OIDC / JWT
• PostgreSQL, MySQL, MongoDB, Redis, Cassandra
• Microservices & API gateways
• Async processing, DB tuning, caching, profiling
• OpenShift deployment