Fractile is a UK AI hardware startup building next-generation inference chips and systems for frontier AI.
<p> </p> <h1>Senior Rust Engineer</h1> <p>Fractile · London or Bristol · Full-time · Hybrid (3 days onsite)</p> <h2>About Fractile</h2> <p>We're building what we believe to be the world's fastest and most energy-efficient AI inference chip from the ground up. Founded in 2022, our 70+ person team is split equally between hardware and software — and the two halves work hand in hand to extract every last drop of performance from the architecture.</p> <p>This is a genuinely interdisciplinary environment, where software engineers shape hardware decisions and vice versa. If you want to work somewhere your contributions have direct, visible impact, you'll fit right in.</p> <h2>The Role</h2> <p>We're building a new Rust engineering team from scratch — greenfield software, with real scope to influence architecture, engineering practices, and direction from day one.</p> <p>You'll write server-side Rust to build a reference implementation of a full AI inference stack, specifically tuned to take advantage of the hardware we're designing. That includes a Linux kernel driver in Rust, as well as the cloud-based tooling needed to run hardware housed in data centres.</p> <p>This is a role for engineers who are energised by unfamiliar problems — you'll research the state of the art in AI inference, form your own views, and implement them. We encourage initiative and reward intellectual curiosity.</p> <h2>What You'll Do</h2> <ul> <li>Build a reference implementation of a full AI inference stack in Rust, tuned to Fractile's custom hardware</li> <li>Write a Linux kernel driver in Rust</li> <li>Develop cloud-based tooling for data centre deployments</li> <li>Research the state of the art in AI inference and bring new ideas into the codebase</li> <li>Collaborate closely with hardware engineers in a true co-design loop</li> <li>Help shape the architecture, direction, and engineering culture of a new team</li> </ul> <h2>What We're Looking For</h2> <p>We're looking for thoughtful problem solvers and technical generalists with the depth to tackle genuinely hard systems challenges. You may be a strong fit if you have:</p> <ul> <li>Strong Rust skills — or senior-level experience in a systems language (C, C++) with demonstrable Rust proficiency via open source or personal projects</li> <li>Experience serving AI workloads (e.g. vLLM, SGLang, or Rust equivalents), OR deep systems-level experience in adjacent areas such as low-latency data movement, paging, caching, or real-time processing</li> <li>A solid background in computer science and the ability to read unfamiliar code, understand it quickly, and identify problem areas</li> <li>Comfort working autonomously in areas of ambiguity — you'll often be the person making sense of a problem for the first time</li> </ul> <p>If you have a portfolio of Rust projects you can share, that will strengthen your application — but it's not a prerequisite.</p> <h2>Our Interview Process</h2> <p>We won't subject you to algorithmic puzzle tests. Our interviews are technical and conversational — we want to understand how you think, how you approach unfamiliar code, and where your depth lies. Expect to discuss systems concepts, Rust specifics, and real engineering trade-offs.</p> <p><strong>Bonus Points</strong></p> <p>These aren't requirements, but they'd make you stand out:</p> <ul> <li>Experience with AI inference frameworks or ML accelerator architectures</li> <li>Prior startup or small-team experience</li> </ul> <h2>Languages</h2> <p>Primary: Rust. Working knowledge of C, C++, and Python also useful.</p> <h2>Why Fractile</h2> <ul> <li>Greenfield Rust codebase — shape it from day one</li> <li>Work directly alongside hardware engineers in a true co-design environment</li> <li>A collaborative culture built on curiosity, initiative, and technical depth</li> <li>Hybrid working: 3 days onsite (London or Bristol), 2 days remote</li> <li>Modern offices in London and Bristol — choose your base</li> <li>Competitive salary and equity in a fast-growing company</li> </ul> <h2>Export Control & Security Clearance</h2> <p>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.</p> <p><em>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.</em></p> <p><strong>Ready to apply? </strong>Send us your CV and a brief note on what excites you about this role.</p>