Senior QA Engineer — Greenfield DDD Platform

Billennium; Wrocław; On-site; PLN 180,000 - 240,000; Full time

Benefits offered by this job

Comprehensive benefits

Career growth

Innovative environment

Engaging community

Annual Mazury event

Welcome pack

Job summary

Billennium is seeking a Senior QA Engineer to join a greenfield project focused on debt servicing and receivables management. You will design, implement and maintain automated UI/API/end-to-end tests for a domain-driven, event-driven architecture.

You will collaborate with Developers and Product Owners in an Agile environment (Kanban), testing REST APIs, distributed services and data through SQL/PostgreSQL. Join a growth-focused company with a strong tech ecosystem and modern tooling.

Qualifications

• 4-5+ years of professional experience as a Tester / QA Engineer, including at least 2 years in a Senior QA role.
• Strong experience in test automation covering UI, API and/or end-to-end testing.
• Hands-on experience testing distributed systems and service integrations.
• Practical experience with REST API testing.
• Experience with asynchronous communication and event-driven architectures, including queues and messaging.
• Experience creating and maintaining functional, regression and integration tests.
• Practical experience with C# and .NET.
• Knowledge of xUnit, Reqnroll and Shouldly.
• Experience with Cypress and/or Playwright.
• Experience with Testcontainers.
• Experience using Postman and/or Apidog.
• Hands-on experience with GitLab CI/CD and/or GitHub Actions, including integrating automated tests into pipelines and modifying existing pipelines.
• Good knowledge of Git, including branches and merge requests.
• Experience with Jira and Xray for test management, reporting and traceability.
• Practical SQL skills and experience with PostgreSQL.
• Experience working in Agile environments, preferably with Kanban.
• Experience working on projects following Domain-Driven Design (DDD) principles.

Responsibilities

• Design, create and maintain test scenarios and test cases covering functional, regression, integration and UAT testing.
• Test distributed systems and integrations between services.
• Test REST APIs and systems based on asynchronous and event-driven communication, including messaging and queues.
• Design, implement and maintain automated UI, API and end-to-end tests.
• Work with C# and .NET, using tools and frameworks such as xUnit, Reqnroll and Shouldly.
• Develop automated tests using Cypress and/or Playwright.
• Use Testcontainers and tools such as Postman or Apidog for API and integration testing.
• Integrate automated tests into CI/CD pipelines, including GitLab CI/CD and GitHub Actions.
• Work with Git, including branching strategies and merge requests.
• Manage testing activities, reporting and traceability using Jira and Xray.
• Use Grafana dashboards and alerts to monitor key quality and system indicators, such as payment throughput, error rates and asynchronous processing delays.
• Work with SQL and PostgreSQL to validate data and support testing activities.
• Collaborate closely with Developers and Product Owners to clarify requirements and identify potential quality risks early.
• Contribute to establishing and improving QA standards, testing practices and automation strategies.
• Share knowledge and support less experienced QA team members.
• Leverage AI-powered tools, such as Copilot and LLMs, to improve QA processes, automation and everyday productivity.

Skills

Test automation

REST API testing

C#/.NET

xUnit

Cypress

Playwright

Testcontainers

Postman

Apidog

GitLab CI/CD

GitHub Actions

Git

Jira

Xray

SQL

PostgreSQL

DDD

Kanban

Tools

Postman

Apidog

Cypress

Playwright

Testcontainers

GitLab CI/CD

GitHub Actions

Git

Jira

Xray

Job description

Billennium is seeking a Senior QA Engineer to join a greenfield project focused on debt servicing and receivables management. You will design, implement and maintain automated UI/API/end-to-end tests for a domain-driven, event-driven architecture.

You will collaborate with Developers and Product Owners in an Agile environment (Kanban), testing REST APIs, distributed services and data through SQL/PostgreSQL. Join a growth-focused company with a strong tech ecosystem and modern tooling.