Backend Engineer

About the Product

We build a real-money iGaming product that combines casino games, operator integrations, real-time multiplayer rounds, and analytics.

Our key engineering challenge is correctness and reliability. Every bet must be settled exactly once, every game outcome must be verifiable, and the system must recover safely from failures during financial transactions.

We’re looking for a Backend Engineer who enjoys working with distributed systems, concurrency, financial transactions, and security-critical logic — and who writes code that remains reliable under pressure.

Responsibilities

• Design, develop, and maintain backend services using Node.js, TypeScript, and NestJS within a microservices architecture.
• Implement transactional game and payment flows, including bets, payouts, refunds, idempotency, retries, and reconciliation.
• Integrate with external wallet and payment providers through APIs, webhooks, and signed requests.
• Develop real-time functionality using WebSockets.
• Design data models and optimize PostgreSQL performance through indexing, query-plan analysis, materialized views, and partitioning.
• Use Redis for state management, distributed locking, atomic operations, and streaming.
• Build event-driven pipelines using message queues, streams, the outbox pattern, and at-least-once delivery.
• Implement security and provably fair game mechanisms using HMAC, hashing, encryption at rest, and secure random number generation.
• Develop internal tools and back-office APIs with appropriate authentication and role-based access control.
• Maintain CI/CD pipelines, containerization, and deployment processes in collaboration with DevOps.
• Write automated tests for critical business logic, including concurrency scenarios and security regressions.

Requirements

• 4+ years of backend development experience with Node.js and TypeScript.
• Strong hands-on experience with NestJS, including modules, dependency injection, guards, interceptors, and microservices.
• Deep knowledge of PostgreSQL, including query optimization and database performance. Experience with an ORM such as Prisma or TypeORM, along with confident use of raw SQL.
• Practical experience with Redis beyond caching, including Lua scripts, transactions, Streams, or Pub/Sub.
• Experience with inter-service communication using gRPC, message brokers, or event streams.
• Solid understanding of distributed systems, including race conditions, idempotency, eventual consistency, and failure recovery.
• Experience with Docker and CI/CD pipelines, such as GitLab CI or GitHub Actions.
• Experience writing automated tests using Jest or similar frameworks.
• Understanding of application security, including authentication and authorization (JWT, OAuth 2.0/OIDC), rate limiting, and the OWASP Top 10.

Will Be a Plus

• Experience in iGaming, betting, fintech, or payment systems.
• Knowledge of provably fair systems and applied cryptography.
• Experience with Kubernetes and cloud platforms such as AWS or GCP.
• Experience with queueing and streaming technologies, including BullMQ, RabbitMQ, or Kafka.
• Experience with analytical databases such as ClickHouse or BigQuery.
• Experience scaling WebSocket-based applications using Socket.IO or ws, including horizontal scaling.
• Knowledge of observability practices, including structured logging, metrics, and distributed tracing.
• A background in mathematics or statistics, particularly probability, RTP calculations, and simulations.

What We Offer

— Competitive salary.
— Remote work.
— International iGaming products and challenging technical tasks.
— Professional growth and opportunities to work with modern technologies.
— A team that actively uses AI as part of the development process.

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