SDET (API Testing | Python) Engineer

SDET (API Testing | Python)

Hybrid | 1 day hybrid in Gdańsk or Warsaw

Are you passionate about quality engineering, test automation, and building robust testing frameworks? Do you enjoy breaking systems before users do? We're looking for a Senior SDET (Software Development Engineer in Test) with strong Python and API testing expertise to help ensure the quality, reliability, and security of mission-critical applications in the fintech and payments industry.

This role combines software development, automation engineering, and quality assurance, with a strong focus on API testing, CI/CD integration, and modern AI-powered engineering practices.

Your Mission

Test Automation & Quality Engineering

• Design, develop, and maintain scalable automated test frameworks using Python.

• Create and execute API test suites for RESTful and microservices-based applications.

• Develop end-to-end, integration, regression, and performance test scenarios.

• Improve test coverage, reliability, and execution efficiency across the platform.

• Collaborate with developers to implement shift-left testing practices.

API Testing

• Validate APIs for functionality, performance, security, and reliability.

• Design comprehensive test cases based on business and technical requirements.

• Perform contract, integration, and end-to-end testing across distributed systems.

• Analyze API logs and troubleshoot complex issues.

CI/CD & Automation

• Integrate automated tests into Jenkins CI/CD pipelines.

• Support continuous testing strategies within Agile delivery teams.

• Improve automation processes to enable faster and safer releases.

• Monitor test execution and provide actionable quality metrics.

AI-Powered Quality Engineering

• Leverage AI tools such as GitHub Copilot, ChatGPT, Claude, and Cline to accelerate test development and improve productivity.

• Utilize AI-assisted approaches for test case generation, defect analysis, and documentation.

• Explore innovative AI-driven testing techniques and share best practices across the team.

Security & Compliance Testing

• Validate application security controls and authentication mechanisms.

• Support testing activities related to compliance and regulatory requirements.

• Ensure high-quality standards for systems processing sensitive financial data.

Collaboration

• Work closely with Developers, Product Managers, Business Analysts, and QA teams.

• Participate in Agile/Scrum ceremonies and planning sessions.

• Contribute to quality strategy, documentation, and process improvements.

Must-Have Skills

Automation & Programming

5+ years of experience in software testing and test automation

Strong hands-on experience with:

• Python

• PyTest

• API automation frameworks

Experience building and maintaining automated test frameworks from scratch

API Testing

Extensive experience testing:

• REST APIs

• Microservices

• Distributed systems

Experience with:

• Postman

• Swagger/OpenAPI

• API mocking tools

• Contract testing

CI/CD & DevOps

Experience with:

• Jenkins

• Git

• CI/CD pipelines

Understanding of modern software delivery practices

Databases

Experience validating data using:

• PostgreSQL

• MySQL

• Oracle

• SQL queries

Quality Engineering

Strong understanding of:

• Test automation best practices

• Integration testing

• Regression testing

• Performance testing

• Defect management

⭐ Nice to Have

• Experience with Selenium, Playwright, or Cypress

• Experience with performance testing tools such as JMeter or Gatling

• Experience working in cloud environments (AWS, Azure, or GCP)

• Knowledge of Docker and Kubernetes

• Familiarity with security testing methodologies

• Open-source contributions

• Technical blogging or community involvement

FinTech & Payments Experience

• 2+ years of experience in fintech, payments, banking, or financial services

• Understanding of payment processing systems and transaction workflows

• Knowledge of PCI DSS compliance requirements

• Familiarity with financial messaging standards and real-time payment systems

• Experience testing highly regulated applications

What You'll Get

Opportunity to work on innovative fintech and payment solutions

High-impact role shaping quality standards and automation strategy

Exposure to cutting-edge AI-powered engineering tools

Hybrid work model (Gdańsk or Warsaw)

Collaborative and supportive engineering culture

Career growth opportunities and continuous learning

Influence on testing frameworks, tooling, and engineering best practices

Ready to elevate software quality through automation, innovation, and engineering excellence?

Join us and help build reliable, secure, and scalable platforms that power the future of digital payments.