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# Full Stack Engineer / Technical Lead B2B SaaS

- **Company:** Client Server
- **Location:** London, UK (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, VoIP, Cursor, Programming Tools, LiveChat, Open Source Technology, Ruby, TypeScript, ReactJS, Claude, Serverless Computing
- **Published:** October 28, 2026
- **Apply:** https://www.apply4u.co.uk/jobs/full-stack-engineer-technical-lead-b2b-saas/53898559

## About the Role

external contributors and open-source collaboration and act as a key interface with the developer community, incorporating feedback into product direction.Location / WFH:You can work from most of the time, collaborating via Slack and meeting up with the team at the dog friendly office in North London for tech talks, lunch and learn events etc. around once a month.About you:You're a senior software engineer with experience of building developer tooling and APIsYou have strong hands-on experience with Ruby, TypeScript and ReactYou have experience within a product focussed B2B SaaS environmentYou have experience of making technical decisions that drive projects and raise the barYou're comfortable with AI tools such as Claude and Cursor and understand how they can be used to optimise processesYou're customer and product focussedYou're collaborative and pragmatic with experience of technically leading and mentoring othersYou have a thorough understanding of Computer Science fundamentals

## Description

Full Stack Engineer / Technical Lead (Ruby TypeScript React) London / Remote to 130kOpportunity for a full stack technologist to join a highly regarded provider of serverless real-time infrastructure for the Internet that processes billions of messages a day and powers everything from live chat and VoIP calls to real-time pricing and stock availability for a multitude of services around the globe.As a Full Stack Engineer / Technical Lead you'll own the technical strategy and architecture for one or more Developer Ecosystems (iOS, Web, Infra/Automation), define and drive best practices for API and SDK design, ensuring consistency, usability and scalability and lead complex, cross-team initiatives to expand and improve client libraries.You'll oversee the full development lifecycle, from design through to release, maintenance and product evolution, mentoring more junior engineers and reviewing contributions, raising the technical bar across the team. You'll also guide and manage