Principal Full Stack Software Engineer

Senior Full Stack Software Engineer At a Glance Senior full stack role… full stack genuinely means full stack here React frontend, Python backend… complex operational software used daily by thousands of field-based users UK remote with quarterly in-person time in Belfast £80,000 to £110,000 Single stage technical interview About the Company Our client is a product engineering organisation building large-scale operational software used daily by thousands of field-based workers across the UK. The technical challenges are real: scale, reliability, data flow, and user experience all matter at this level, and the team operates with the pace and standards to match. This is a business where engineering quality is the expectation and senior engineers have genuine influence over how the product evolves, not just tickets to close. The Role This is not a surface-level full stack position. The team is building complex operational software that genuinely needs someone who has delivered meaningful complexity across both React and Python, shaped architecture, and worked closely with Product from early ideation through to production. You will own solutions end to end, contribute to technical direction, and help raise the bar for the engineers around you. If you want autonomy, real architectural influence, and a team that takes quality seriously, this is worth a look. Key Responsibilities Partner with Product from ideation through to delivery, shaping technical solutions from the outset Design and build substantial Python backend functionality underpinning complex operational workflows Deliver high-quality React-based frontend experiences that are performant, intuitive, and resilient Lead architectural discussions around system design, data flow, and technical trade-offs Write clean, maintainable, well-tested production code Drive improvements across engineering standards, patterns, and best practices Mentor engineers across the wider team and raise the bar for technical capability What You’ll Need Essential: 5+ years of commercial software engineering experience with genuine depth across both backend and frontend Strong commercial React experience, including component architecture and state management Solid Python backend engineering experience, ideally within a modern framework Demonstrable experience influencing system design and architecture, not simply implementing Comfortable working within distributed, service-oriented, or event-driven systems Strong understanding of data modelling, API design, and performance optimisation Right to work in the UK Nice to have: Experience building software for field-based or operationally complex environments Background in product-led teams with early-stage ideation involvement Why Apply? £80,000 to £110,000 depending on experience UK remote with flexibility and quarterly team time in Belfast Complex, high-scale product challenges with visible impact at scale Genuine technical leadership… architecture, standards, and direction are yours to shape Single stage technical interview… no multi-month processes Engineering culture where quality is the standard, not the aspiration Next Steps To discuss in confidence, connect with Ryan Quinn on LinkedIn or reach out directly at . That one is clean and ready to post. All seven sections are complete, salary and stack are confirmed, client is unnamed, and the checklist is clear. Skills: JavaScript AWS TypeScript Python Go Java Benefits: Options