Backend Developer (Node.js) at Optiplay in Ukraine

We're looking for a Middle+/Senior Backend Developer - first and foremost a strong, well-rounded backend engineer. The role splits roughly 70/30: 70% designing and maintaining our external integrations (casino operators and partner platforms), 30% general backend/platform work and system design.

What you'll do

• Design, build, and maintain integrations with casino operators and partner platforms (wallet/transaction APIs, game launch, and reporting contracts), owning the full lifecycle from contract design to production monitoring;
• Build resilient integration layers: retries, idempotency, timeouts, error mapping, and graceful degradation when a third party misbehaves;
• Contribute to core backend services and platform features - APIs, messaging flows, data models, shared modules;
• Take part in slot game development on our game logic platform - implementing game mechanics and mathematics alongside the core team;
• Define and improve integration testing practices: contract testing, mocking/stubs, e2e, and stress/load testing;
• Work closely with Game Logic, Product, and DevOps teams to keep integration contracts stable as the platform evolves;
• Participate in code reviews, technical decisions, and architecture discussions across the backend.

What you bring

• 3-5+ years of backend development experience with Node.js + TypeScript, including ownership of non-trivial systems;
• Proven experience designing and maintaining external integrations (REST/HTTP, XML/SOAP, RPC-style, or webhook-based);
• Solid understanding of modular, service-oriented backend architecture, ideally from enterprise or scale-up environments;
• Practical experience with message brokers (RabbitMQ or Kafka) and event-driven, queue-based design;
• Strong grasp of integration testing approaches: contract testing, mocking, e2e, and stress testing;
• Confident with PostgreSQL and Redis, CI/CD, Git, and monitoring/observability tools (Grafana, Loki, Tempo);
• Comfortable with AWS, Docker, and Kubernetes for containerized deployments.

Nice to have

• Experience in iGaming, gambling platforms, or RNG/game provider integrations;
• Familiarity with ArgoCD and GitOps workflows.

• 21 vacation days + 2 extra day-offs annually;
• 12 paid sick days;
• Fully remote format - work from anywhere you feel productive;
• Flexible schedule: start your day anytime between 08:00-11:00 CET;
• Fixed budget for health insurance and gym/fitness;
• Provided all required work equipment;
• Zero bureaucracy and direct communication with founders and C-level;
• Minimal meetings, async-friendly workflow;
• Startup energy: fast motion, creativity, and tight-knit communication;
• Business trips and team meetups several times per year;
• Multiple salary payout options (flexible formats);
• …And many more perks unlocked after we hit break-even.