Senior or Mid Backend Software Engineer (m/f/d)

Your day-to-day

• Implement new microservices and extend existing ones in Go.
• Help groom user-story requirements and surface performance and scaling concerns early.
• Write unit, integration, and API tests; review pull requests.
• Tune data models in DynamoDB and Postgres for low-latency, high-throughput workloads.
• Pair with DevOps on CI/CD and observability improvements.
• Participate in an on-call rotation while building a highly available fintech system.

Additional tasks of the Senior

• Design and drive high-scale, low-latency services handling tens of thousands of orders per second.
• Lead architecture reviews, challenge assumptions, and keep technical debt in check.
• Partner with Product on roadmap feasibility and effort sizing.
• Mentor less experienced colleagues.

Perfect candidate profile

• 3+ years of professional backend experience, ideally including 1+ year in Go.
• Solid understanding of cloud-native design, including RESTful APIs and event-driven patterns.
• Working SQL and NoSQL skills, with knowledge of when to use each.
• Ability to diagnose performance bottlenecks in distributed systems.
• Ability to work on-site in Warsaw twice a week, Tuesday and Thursday, and remotely otherwise.

Nice to have

• Exposure to serverless architectures on AWS.
• Knowledge of automated trading, market data, FIX, or cryptocurrency exchanges.
• Familiarity with Infrastructure as Code using Terraform or CDK.

What we offer

• An experienced, welcoming team focused on clean, well-tested code.
• Features shipped directly to production for live traders.
• Flexible hours, modern tooling, and work in the fintech domain.
• Occasional work travel to Germany, including Munich and Berlin.
• 20 days of PTO on B2B.
• Multisport card.