Principal Full Stack Developer

Location: London office, hybrid, minimum 2 days a week.

A unique opportunity for a Principal Full Stack Developer to join a very well-funded early-stage technology company. Initially working remotely, with plans for a hybrid London office, you will play a pivotal role in transforming an innovative prototype into a production-ready platform while helping shape the long‑term technical direction of the product. This is an exciting opportunity to work with a modern technology stack, take ownership of key technical decisions, and help build and lead the engineering function as the company continues to grow.

Due to the nature of some client projects, you must be willing and eligible to obtain UK Security Clearance. You can join the team and work on other commercial projects while your clearance application is progressing.

• Strong commercial experience developing full‑stack applications using React, Next.js, TypeScript, Python, PostgreSQL, REST APIs, Docker and AWS.
• Previous technical leadership experience, including mentoring engineers and driving engineering best practices.
• Experience designing scalable, maintainable software architectures and confidently making key technical decisions.
• Commercial experience working with CI/CD pipelines and modern software development practices.
• Enjoy working in a fast‑paced start‑up environment where you can take ownership, influence product direction, and have a genuine impact on the company's success.
• You must be eligible to obtain UK SC Security Clearance due to the nature of some projects (this usually means you have been a UK resident for the past 5 years, have a clean criminal record, etc.). Existing SC Clearance would be a benefit.
• Experience with any of the following would be beneficial: Infrastructure as Code (IaC), Terraform, Go, Amazon CloudWatch, automated testing frameworks.

• Shape the technical direction and long‑term evolution of the product.
• Lead architectural decisions, ensuring solutions are scalable, maintainable and secure.
• Design, develop and deliver software across the front‑end, back‑end, and API layers.
• Establish engineering standards, coding practices and development processes to support a high‑performing team.
• Mentor and support engineers, promoting best practice and continuous improvement.
• Work closely with engineers, product stakeholders and the wider business to translate requirements into high‑quality software solutions.
• Identify opportunities to improve system performance, reliability and scalability as the platform evolves.

• The opportunity to join a well‑funded technology start‑up at an exciting stage of its growth journey.
• A genuine chance to shape both the product and the long‑term technical direction of the platform.
• The opportunity to work with a modern, cutting‑edge technology stack in a highly innovative environment.
• Significant ownership and autonomy, with the ability to make a real impact from day one.
• An excellent salary and benefits package.

If you would like to enquire about this unique full‑stack opportunity, we would love to hear from you. Please send an up‑to‑date CV via the relevant link.

We’re committed to creating an inclusive and accessible recruitment process. If you require reasonable adjustments for your application or during the review process, please highlight this by separately emailing applications@redtech-recruit.com.

RedTech Recruitment Ltd focuses on finding roles for Engineers and Scientists. Even if the above role isn’t of interest, please visit our website to see our other opportunities. We are an equal opportunity employer and value diversity at RedTech. We do not discriminate on the basis of race, religion, colour, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.