Java Principal Software Engineer

Principal Software Engineer Java

📍Remote UK | 🌍 Global Fintech | 💳 Payments Innovation

A high-growth global fintech, renowned for delivering world-class payments-related software and technology, is looking to expand its engineering team. As this client continues to scale its platform to meet increasing global demand, they’re seeking experienced Software Engineers to help shape the future of their merchant-first payments ecosystem.

👋 About the Company

The company is building the next generation of capabilities to power a smarter, more seamless payments experience. Their teams are small, empowered, and outcome-focused. They value curiosity, pragmatism, and engineering excellence. The environment is collaborative and fast-paced, with a strong focus on outcomes over outputs.

This is a place for engineers who are driven by solving real-world problems with elegant, modular, and testable code, and who want their work to make a real difference.

🚀 About the Role

The Principle Software Engineer will be responsible for the design and development of backend services and portals that power the core payment processing platform. The work spans across a variety of languages, frameworks, and modern engineering techniques such as Behaviour-Driven Development (BDD) and CI/CD.

Engineers are trusted with high levels of autonomy, free to focus on solving technical problems without bureaucracy getting in the way.

Key responsibilities:

• Translate merchant and partner requirements into scalable, high-performance software solutions.
• Design and implement clean, testable, and modular systems with clear separation of concerns.
• Collaborate across small, cross-functional teams to deliver meaningful outcomes.
• Contribute to the continuous improvement of engineering practices and processes.
• Take ownership across the full development lifecycle, from requirements through to deployment.

🧠 What’s Needed

This is not just a role for tool users — the team is looking for systems thinkers who understand architecture, modularity, and long-term maintainability. Candidates should have deep knowledge of core engineering principles, not just familiarity with frameworks.

Essential skills & experience:

• 8–10 years’ experience in software engineering.
• Strong command of object-oriented programming and SOLID principles.
• Expertise in at least one OO language (e.g. Java, C#, Ruby, Go).
• Solid experience in server-side development and database design.
• Proficient in SQL, joins, indexing, stored procedures, and ER modelling.
• Familiarity with front-end fundamentals (HTML, CSS, JavaScript) is a plus.
• Comfortable working independently or as part of a wider team.
• Strong problem-solving and communication skills.

Desirable:

• Experience with CI/CD pipelines and Behaviour-Driven Development (BDD).
• Familiarity with scalable system design and message-oriented middleware.
• Contribution to reusable libraries or frameworks.
• Experience mentoring and guiding other engineers.

💡 Engineering Culture

• Small Teams, Big Impact: Engineers are given clarity on goals and the autonomy to deliver without red tape.
• Growth Mindset: There’s a strong emphasis on learning, experimentation, and continuous improvement.
• Merchant-Focused: Solutions are designed to address real-world merchant challenges, with a collaborative and quality-driven mindset.

⚠️ Who Might Not Be a Fit

The client has found that some candidates struggle in this environment due to:

• Shallow understanding of OOP and poor application of SOLID principles.
• Procedural or monolithic approaches that ignore modularity and testability.
• Limited systems thinking or lack of experience with scalable architecture.
• Weak relational database knowledge, especially around indexing, joins, and stored procedures.
• Minimal exposure to collaborative practices like code reviews, refactoring, and shared ownership.

Engineers who thrive here are thoughtful about architecture, confident in navigating ambiguity, and committed to building robust, maintainable systems.

📬 Interested?

This is a fantastic opportunity to work in a fast-moving, high-impact engineering environment where your work directly contributes to powering one of the world’s leading fintech platforms.

If you're a Principal level engineer ready to take on meaningful challenges, and want to be part of a company that genuinely values technical craft please get in touch to learn more.