Senior Go Engineer - Payment Gateway Solutions

About the role

Colibrix One builds AI-powered payment technologies for PSPs, EMIs and neobanks across the EU and UK, and is looking for an experienced Go Engineer to contribute to its payment gateway product. The gateway connects merchants and financial institutions to process online payments in real time, handling routing, encryption and tokenization, fraud and risk checks, and integration with acquirers, aggregators and alternative payment methods. The role suits someone who can influence and mentor colleagues through expertise.

Key responsibilities

• Design and develop Go-based services for the payment gateway, focusing on stability, fault tolerance and correct handling of financial operations
• Translate business requirements into technical specifications, including API design, data models and integrations with external providers
• Build solutions compliant with security requirements such as PCI DSS and secure handling of sensitive data
• Analyze and optimize performance, including code profiling, concurrency and data storage efficiency
• Take part in microservice architecture: boundaries, communication patterns, load balancing, queues/streaming and data storage
• Write maintainable, testable code with unit and integration tests, and take part in code reviews

Required profile

• 3-5 years of Go experience on backend systems and about 5 years in fintech
• Knowledge of distributed systems, microservices and API design (REST/RPC)
• Experience with SQL and NoSQL databases, message brokers (Kafka, NATS) and caching systems
• CI/CD familiarity, preferably GitLab, and AWS experience
• Fluent written and spoken English and Russian
• Security-by-design mindset and understanding of PCI DSS, GDPR and other fintech regulations
• Experience optimizing performance and building high-availability systems, and integrating with payment providers, processors or anti-fraud systems

Required skills

• Go
• PostgreSQL/MySQL, MongoDB/Redis
• Kafka, NATS
• REST/gRPC, GitLab CI/CD, Prometheus, Grafana
• Observability: logging, metrics, tracing (OpenTelemetry)

What we offer

• A chance to shape fintech solutions in a growing company
• A collaborative, horizontal team structure
• Learning and development opportunities
• Competitive salary and benefits package
• Flexible work arrangements