Senior Java Developer

Why this role exists:
This role exists to design, build, and maintain backend services across the Casino platform bonus and promotional mechanics, wallet and transaction flows, game launch and catalog, and game provider integrations ensuring reliability, correctness, and performance under high load.
What you'll drive:
Casino platform services
Design and develop Spring Boot microservices across the casino domain: bonus processing, game launch, lobby and game catalog management.
Implement and evolve promotional mechanics end-to-end from bonus crediting and wagering logic to expiry and settlement with correctness guarantees on real money.
Integrate third-party game providers, game launch, wallet callbacks (bet/win/refund), provider-side bonus features.
Build and evolve REST APIs consumed by internal services and external providers, including request signing, authentication, and API versioning.
Reliability & correctness
Ensure correctness of real-money transaction and bonus flows idempotency, retries, timeouts, graceful degradation of downstream calls.
Work with Redis for caching and session state; tune service performance under production load.
Own observability: metrics (Micrometer/Prometheus, Grafana dashboards), structured logging, alerting.
Quality & delivery
Write and maintain unit, integration, and functional tests (JUnit 5, Testcontainers).
Ship via GitLab CI to Kubernetes; participate in code review and incident investigation.
What makes you a GR8 fit:
Must-have
5+ years of experience in back end.
Commercial experience with strong proficiency in Java (17+) and Spring Boot 3.x (Web, Security, Data, Actuator).
Experience building business-critical domain logic (payments, bonuses, billing, or similar money-adjacent flows).
Solid experience integrating third-party REST APIs and designing your own.
Understanding of distributed systems basics: idempotency, consistency, timeouts, retries, caching.
Experience with SQL and at least one NoSQL store (Redis, Cassandra, or Elasticsearch).
Upper-intermediate or higher level of English.
Nice-to-have
Scala experience (parts of our wallet platform run on Scala / Play / Akka).
Experience with Kafka and event-driven architectures (some of our services use Spring Cloud Stream).
Experience running services on Kubernetes; familiarity with GitLab CI.
Familiarity with Prometheus and Grafana.
iGaming / betting domain experience.