Senior Backend Engineer

Quick Facts

• Role: Senior Backend Engineer

• Focus: Distributed backend services and APIs for payment authorization and financial ledger/settlement processes

Description

You will design, develop, and maintain secure, scalable, and reliable distributed backend services and APIs. The work includes event-driven architecture, integrations between services, and end-to-end ownership from requirements and technical design through testing, deployment, and production support. You will also monitor production, investigate incidents, perform root-cause analysis, and improve systems, while mentoring others and contributing to engineering standards.

Responsibilities

• Design, develop, and maintain distributed backend services for payment authorization, financial ledgers, settlements, and related payment processes

• Build scalable, secure, and reliable APIs with a focus on performance, maintainability, and resilience

• Develop event-driven architectures and implement integrations between distributed services

• Own backend solutions end-to-end across the software development lifecycle (analysis, design, implementation, testing, deployment, production support)

• Design and maintain domain events and ensure reliable data exchange between systems

• Collaborate with engineering and product teams on technical requirements and architectural decisions

• Monitor production, handle incidents, perform root-cause analysis, and implement improvements

• Review code, mentor developers, and support engineering best practices and standards

Requirements

• 5+ years of commercial backend development experience with Java, C#/.NET, Rust, or Node.js

• Practical experience with distributed systems and event-driven architectures

• Strong distributed systems knowledge: consistency models, Saga patterns, idempotency, Outbox pattern

• Experience building production-grade backend services and APIs

• Hands-on CI/CD, production monitoring, and observability

• Relational database knowledge, preferably PostgreSQL

• Automated testing experience: unit, integration, contract testing

• Daily use of AI-assisted development tools (e.g., GitHub Copilot, ChatGPT, Claude)

• Ability to write clean, maintainable, well-tested code

• Very good English and Polish

Benefits

• Private medical care

• Sports card

• Training courses

• Hybrid work model: preferably 1 day per week in the Warsaw or Cracow office

• International working environment and international projects

• Small team