Senior Java Developer

GR8 _TECH builds B2B iGaming platforms for operators who play to lead.
We deliver full-cycle, high-impact tech designed to scale — from seamless integrations and expert consulting to long-term operational support. Our platform powers millions of active players and drives real business growth. Call it what it is: the iGaming Platform for Champions.
With 1000+ GR8 people across locations and time zones, we don’t just ship technology — we help operators build success stories across brands, markets, and geos.
Our ambition drives us. Our people make it real.
If you’re a challenger in spirit and a champion in action — join us.
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.
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Why you’ll love working here:
Benefits Cafeteria — annual budget you allocate to:
Sports • Medical • Mental health • Home office • Languages.
Work-life & support

- Paid maternity/paternity leave + monthly childcare allowance.

- 20+ vacation days, unlimited sick leave, emergency time off.

- Remote-first + tech support + coworking compensation.

- Team events (online/offline/offsite).

- Learning culture with internal courses + growth programs.
Our culture & core values:
GR8_TECH culture is how we win — through trust, ownership, and a growth mindset. We move fast, stay curious, and keep it real, with open feedback, room to experiment, and a team that’s got your back.
FUELLED BY TRUST : we’re open, honest, and have each other’s backs.
OWN YOUR GAME : we take initiative and own what we do.
ACCELER8 : we move fast, focus smart, and keep it simple.
CHALLENGE ACCEPTED : we grow through challenges and stay curious.
BULLETPROOF : we’re resilient, ready, and always have a plan.