Senior Backend Engineer (Go)

About the role

X-FLOW is a mobile game development company known for Happy Color, a leading digital coloring book app. We are looking for a Senior Backend Engineer (Go) to join the team and help scale the backend of our flagship project.

Key responsibilities

• Design and develop microservices in Go using REST and gRPC, and build public and internal APIs.
• Integrate with external services, create contracts, and implement event‑driven integrations with Kafka or NATS.
• Optimize performance, profile applications, reduce latency and ensure scalability.
• Design database schemas, manage migrations, indexing and query optimization for PostgreSQL/MySQL.
• Maintain CI/CD pipelines, Docker containers and Kubernetes clusters on AWS.
• Write comprehensive unit, integration and end‑to‑end tests and conduct code reviews.
• Implement observability through logging, metrics, alerting and tracing.
• Participate in architectural design, RFCs and ADRs.

Required profile

• 3+ years of commercial software development experience, including 3+ years with Golang.
• Strong understanding of backend architecture, API design, microservices and distributed systems.
• Proficiency with PostgreSQL/MySQL, Redis and event‑driven queues such as Kafka or NATS.
• Experience with CI/CD (GitLab CI), Docker, and cloud infrastructure on AWS.
• Good command of English (B1) and Russian (C1).

Required skills

• Go (goroutines, channels, context, generics, profiling).
• gRPC and REST API development.
• PostgreSQL, MySQL, Redis.
• Kafka, NATS.
• Docker, Kubernetes, AWS.
• GitLab CI, Helm.
• Prometheus, Grafana, Loki, OpenTelemetry, Sentry.
• OAuth2, JWT.

What we offer

• Competitive salary and benefits package.
• Flexible working hours with remote/office options.
• Opportunities for career growth and professional development.
• A creative, inclusive culture that celebrates diversity.