9 of 9 Principal Software Engineer Jobs in London

Principal Software Engineer - Backend Location: Remote first (Occasional travel to London) Salary: £95,000 - £120,000 + equity + benefits An established, global technology business within the hospitality-tech industry is seeking an accomplished Principal Software Engineer to lead the design and delivery … with engineering leadership to define best practices, coding standards, and long-term technical strategy. Design, develop, and oversee the delivery of robust, production-grade software built using Python, Django, Cloud Firestore, BigQuery, and Elasticsearch. Mentor and guide engineers at all levels, fostering a culture of technical excellence and continuous ...

Principal Software Engineer Fully Remote | Permanent | £85,000 - £115,000 Harrington Starr has partnered with a leading Global Payments Technology company who are seeking to hire a Principal Software Engineer to join their senior engineering leadership team. This is a rare opportunity to combine … performance systems at global scale. Career progression in a fast-growing international technology business. Key skills required: 10+ years' experience in enterprise architecture and software engineering. Proven expertise in .NET with strong SaaS and API platform experience. Hands-on track record designing highly scalable, high-performance systems. Strong leadership ...

Principal Software Engineer .NET £90,000-£110,000 Remote (UK) Do you thrive on building scalable solutions that power commerce worldwide? We're partnering with a rapidly expanding global payment platform fresh off a transformative acquisition. They're engineering a robust, merchant-centric ecosystem built on quality … resilience, and scale - and they need exceptional .NET Software Engineers to drive this evolution. Your Impact: Design and develop mission-critical platform services, APIs, and merchant portals Drive performance optimisation and system reliability through intelligent engineering Champion engineering excellence in architecture, code quality, and delivery Partner with cross-functional ...

About The Role Deadline for applications: 11:59pm on 31st October 2025 Were looking for a Principal Software Engineer to shape the technical direction of high-profile projects and lead the delivery of modern, scalable software. We use technology to create impactful, human-centred solutions that make … working closely with senior stakeholders, mentoring engineers across multiple teams, and line managing a small group of engineers while helping shape our approach to software delivery, architecture, and engineering culture. Responsibilities Lead the design and development of advanced software solutions, ensuring high standards of quality, security and scalability. ...

startup building genuinely transformational tooling for some of the most document-heavy industries out there. They're now looking for a Staff or Principal Software Engineer who wants to design and ship AI-driven product capabilities end-to-end, from the first customer conversation … Confident designing and maintaining APIs and integrations Comfortable working end-to-end across architecture, coding, deployment and customer delivery You think like a product engineer, working in tight loops, understanding the "why," and focusing on real user value You use AI coding tools as leverage rather than novelty Curious ...

About The Role Deadline for applications: 11:59pm on 31st October 2025 Were looking for a Principal Software Engineer to shape the technical direction of high-profile projects and lead the delivery of modern, scalable software. We use technology to create impactful, human-centred solutions that make ...

Front End-leaning Principal engineer who wants to combine your experience in web and AI to help unlock other engineering teams, this might be the role for you. This role will also be an opportunity to apply AI to real-world problems inside a healthy, profitable, and rapidly … time. You will help them stay ahead of the curve by solving both technical and sociotechnical problems. You would be joining a squad of Principal engineers with different expertise that serves as a centre of excellence to the 16+ engineering teams in the wider engineering function. Your domain? Everything ...

Senior Backend Engineer | London | £100,000 - £160,000 | Python | FastAPI | Systems Location: London based - hybrid Salary: £100,000 - £160,000 + equity Tech Stack: Backend: Python (FastAPI) Cursor, Claude Code AWS Are you a backend engineer who cares more about building robust systems than chasing AI hype … them into reliable systems Contribute to architectural decisions and long term platform evolution Requirements for Success Strong experience as a backend or systems focused engineer Deep Python experience with excellent engineering fundamentals, or equivalent depth in a strongly typed language Strong SQL skills and experience designing schemas Experience building ...

Role : Senior, Staff & Principal Engineers Salary range: 90 - 160k (+ equity) Senior: 90-115k | Staff: 120-135k | Principal: 140-160k Location : Central London (x3 days per week onsite - Tue/Wed/Thurs) Tech stack includes : Typescript, React, Material UI, NodeJS, Postgres, AWS (Serverless) Current ...