Developer Experience Engineer

Fractile London or Bristol Full-time Hybrid About Fractile Fractile is building silicon, systems, and software that redefine the frontier of AI — running the world's largest language models at radically higher speed and lower cost. Founded in 2022, our 100+ person team spans hardware and software, and we're growing fast. But revolutionary hardware only matters if developers can get their models running on it quickly and predictably. That's where you come in. The Role We're looking for Developer Experience Engineers to design and build the tooling and workflows that companies will use to optimise their large language models on Fractile's next-generation inference hardware. This is a role that sits at the intersection of deep systems knowledge and genuine empathy for developers. You'll shape how the outside world experiences Fractile — from a customer's first quickstart guide through to advanced performance profiling. You'll also be the voice of that external developer inside the company, turning real deployment pain into roadmap priorities. You'll work in a tight hardware-software co-design loop alongside ML compiler, runtime, systems software, and silicon engineers — influencing APIs and abstractions before they're set in stone. What You'll Do Design and build the tools customers use to run, optimise, and monitor large language models on Fractile hardwareBuild interfaces to diagnostic, profiling, and observability tools that help developers understand performance, debug issues, and optimise deploymentsWrite documentation, quickstarts, reference examples, and tutorials that define a developer's first and lasting impression of our platformAct as the voice of the external developer inside Fractile — translating real deployment pain into roadmap prioritiesCollaborate with ML compiler, runtime, systems software, and silicon teams to shape APIs and abstractions early in the design process What We're Looking For About We care about depth of knowledge, empathy for developers, and a genuine drive to make complex things feel simple. You'll be a strong fit if you have: Strong software engineering fundamentals and experience building developer-facing tooling, SDKs, APIs, or platforms that other engineers depend onExcellent Python skills, with solid experience in one or more systems languages such as Rust, C++, or GoA good understanding of modern ML workloads and the practical challenges of deploying large language models to productionAn instinct for reducing the number of steps, surprises, and rough edges between a user and a working resultA Computer Science, Electronic Engineering, Maths, Physics, or related degree, and 5+ years of industry experience Bonus Points These Aren't Requirements, But They'd Make You Stand Out Experience with inference serving stacks (vLLM, SGLang, TensorRT-LLM, Triton) or ML compiler and runtime toolchainsExperience working with GPUs, TPUs, or other ML acceleratorsA track record of contributing to or maintaining open source developer tools or ML ecosystem projectsExperience writing technical documentation and developer education contentPrior startup or small-team experience How We Work Ownership and autonomy — you'll have real agency to drive your work forwardRapid iteration — we work directly with leadership to move from idea to product on ambitious timelinesFull-stack collaboration — hardware, software, silicon, and modelling teams work closely togetherHybrid working: 3 days onsite (London or Bristol), 2 days remoteA team-first mindset — the best idea gets shipped, regardless of where it comes from Why Fractile Shape how the world's developers experience next-generation AI hardwareA collaborative culture built on curiosity, initiative, and technical depthModern offices in London and Bristol — choose your baseCompetitive salary and equity in a fast-growing company Export Control & Security Clearance Certain roles may involve working on technologies subject to export restrictions. Applicants may be required to undergo additional eligibility checks to ensure compliance with applicable law. Fractile is committed to building a diverse and inclusive team. We welcome applications from people of all backgrounds and actively encourage candidates from underrepresented groups to apply. Ready to apply? Send us your CV and a brief note on what excites you about this role.