QA Engineer (AI)

Working Model: Hybrid Working or Remote

Employment Status: Full-time, Permanent

Working hours: Monday to Friday

Office Location: Sofia, Bulgaria

Reporting to: Head of Engineering, Bulgaria

Picture yourself at the cutting edge of payments innovation, where each project has the potential to transform the industry. We’re on a dynamic path to redefine what’s possible, with a powerful portfolio that’s set to surpass the competition and position us as a global leader. This is your chance to join us at a pivotal moment in our journey—where your work can make an extraordinary impact.

If you've ever dreamed of being part of something remarkable from the beginning, this is your opportunity. As we grow, your role will shape the future, impact customers worldwide, and drive us toward becoming a game-changer in payments. Join us, and let’s create something truly groundbreaking together.

In this role you will add value to PXP by:

As a QA Engineer at PXP, you’ll play a key role in ensuring the quality, reliability, and performance of the technology that powers our payment platform. This is a hands-on, collaborative position where you’ll work closely with cross-functional teams to build and refine robust test automation in a fast-paced, agile environment.

While you will test our broader backend applications, we are looking for a QA professional who has a solid conceptual understanding of AI agent orchestration. Your familiarity with how automated agent systems execute multi-step workflows, manage state, and use tool-calling boundaries will be vital in designing validation and testing strategies that can handle both deterministic payment logic and non-deterministic AI behaviors.

A typical week might involve:

• Collaborating with stakeholders to understand business requirements and translating them into comprehensive QA test strategies on the PXP platform.
• Designing end-to-end testing frameworks for highly complex projects, covering gateway and acquiring services across multiple verticals.
• Selecting appropriate automation technologies, frameworks, and metrics to achieve optimal test coverage.
• Implementing quality guardrails that account for flow-based processing and understanding how to mock or evaluate systems connected to orchestrated AI agents.
• Developing, executing, and maintaining high-quality automated test suites to ensure the scalability and reliability of our platform.
• Providing technical leadership and guidance to development and QA teams on test automation best practices.
• Reviewing system architectures to identify technical risks, boundary issues, or edge cases within complex, asynchronous data flows.
• Staying up-to-date with industry trends, specifically emerging methodologies for testing agentic AI structures and automated backend systems.

We are looking for someone who:

• Bachelor's degree in Computer Science or a related field.
• Proven experience in software testing, including manual and robust automated testing.
• Strong understanding of C# .NET Core, SQL Server, and backend validation techniques.
• Deep experience with test automation frameworks and tools, including familiarity with SpecFlow for behavior-driven development (BDD) testing.
• A strong conceptual understanding of AI agent orchestration (state management, loop execution, and function calling boundaries) so you know how to map out test cases for systems that interact with AI layers.
• Solid understanding of software development lifecycles, CI/CD pipelines, and agile practices.
• Excellent attention to detail, strong problem-solving skills, and great communication habits.

We would love someone to have any of the following:

• Online payments and financial systems
• Understanding of the challenges in an enterprise, multi-server, multithreading system

What we can offer you:

You will be joining us at a pivotal moment, where your contributions will directly shape our growth and future success, setting you on the ground floor of something extraordinary.

At PXP, we don’t just offer a job—we offer an opportunity to build something extraordinary. You’ll work on transformative projects, collaborate with passionate colleagues, and see the tangible impact of your efforts on our journey to becoming a global payments leader.

• Growth Opportunities: Be part of a company with an ambitious vision, where your role evolves as the company grows.
• Cutting-Edge Environment: Work with the latest tools and technologies to drive innovation in the payments industry.
• Collaborative Culture: Join a supportive team that values creativity, collaboration, and shared success.
• Flexibility: Benefit from hybrid or remote working options that allow you to balance professional and personal priorities, depending on your location.
• Competitive Package: Enjoy a competitive salary, performance bonuses, and a range of benefits tailored to your location.
• Impactful Work: Play a critical role in shaping the future of payments and making a difference for customers worldwide.

About us

PXP is a well-established and respected name within the card payment industry.

We boast an impressive and diverse client database across the globe and have over 30 years of experience within the payments space.

Our people are employed across our regional offices located in the UK, Austria, Bulgaria, India and the US.

PXP are a leading payment provider with a reputation for a reliable payment and acquiring platform as well as offering operational excellence and best-in-class service for all of our clients.

Take your career to the next level and join us as we redefine the payments industry. With our CARE values at the core of everything we do, let’s innovate together.

CARE: Customer at our Core, Accountability, Respect, and Excellence.

These principles guide everything we do, from how we interact with our customers to how we support one another as a team.