Senior Software Engineer in Test (SDET)

Quick Facts - Role: Senior Software Engineer in Test (SDET) (embedded) - Work model: Hybrid - Location: Kraków, Gdańsk, or Warsaw Description

In an embedded Engineering in Test role, you join a product-engineering team to own quality strategy and build high-leverage, shared automated testing tooling that the team can use across the organization.

You will design, develop, and maintain automated test suites across multiple layers (unit, integration, API, end-to-end, regression, and performance), and evolve internal test automation frameworks and shared utilities to improve coverage, speed, and reliability.

You will integrate tests into CI/CD pipelines (GitHub Actions), grow contract testing between services, and turn production observability signals (Sentry, Grafana, ELK) into quality feedback that closes the loop between live behavior and test coverage.

Role description & Responsibilities - Design, develop, and maintain automated test suites across unit, integration, API, end-to-end, regression, and performance - Build and evolve internal test automation frameworks, libraries, and shared utilities - Integrate automated tests into CI/CD pipelines on GitHub Actions - Introduce and grow contract testing between services to make cross-service refactors safer - Use production observability (Sentry, Grafana, ELK) as a quality signal to improve test coverage - Collaborate with security on testing for sensitive and regulated flows - Develop and execute performance, load, and stress tests with k6 and surface bottlenecks early - Collaborate with developers and product manager to define test strategies for new features/services - Analyse test failures and production incidents to find root causes and implement preventive measures - Apply AI-assisted tooling for test generation, exploratory testing, and test data Requirements - 6+ years of professional experience as a Senior Developer in Test / Senior Engineer in Test / Senior SDET - Strong coding skills in at least one major language: Go, Python, Ruby/Rails, JavaScript, TypeScript - Hands-on experience building test automation frameworks from scratch using Playwright - Experience testing RESTful APIs using Bruno, Postman, or similar - Experience with contract testing between services (e.g., Pact) - Working knowledge of CI/CD and integrating test suites into build pipelines - Experience with AI-assisted tools in testing workflow or strong eagerness to learn and experiment - Strong analytical and troubleshooting skills (flake tests, race conditions, complex integrations) - Proficiency with Git and collaborative development workflows - Ownership mindset: ship, monitor, fix - Clear communication across cross-functional teams in an agile environment - Strong command of English (spoken and written) Benefits - Opportunity to build high-leverage core-domain tooling - Culture of good engineering practices and continuous improvement - Daily deployments to production - Modern tech stack across backend, frontend, databases, infrastructure, monitoring, and testing - Private healthcare, wellness budget, travel stipend, gym/transport subsidy, free access to AirHelp services