Job Description

Flux Computing designs and manufactures optical processors to train and run inference on large AI models. Join us in London to be part of a highly motivated and skilled team that thrives on delivering impact and innovation at speed.

The Contract:

We're seeking a highly experienced and motivated Compiler Engineer [contractor] for a 3 month engagement outside of IR-35 to work on our ML Backend and functional simulator for our next-generation OTPUs with our permanent team. Your mandate will be to deliver a production-ready ML backend (compiler, runtime, debugger) and functional simulator that can accurately run most large AI models.


This role demands deep expertise in C and C++ programming, ML framework internals, compiler construction, and optimisation techniques.

Responsibilities

Implement Runtime:

Build a runtime that seamlessly integrates with PyTorch, JAX, and TensorFlow (PJRT) for both training and inference execution patterns. The runtime must support asynchronous execution and multiple devices.

Implement Compiler:

Build a compiler that is extensible to future optimisation patterns across operation fusion, layout optimisation, tiling, and scheduling.

Implement Debugger & Diagnostics:

Support optional runtime assertions and compile-time dumps, tensorboard timelines, and JAX I/O callbacks.

Implement Functional Simulator:

Build a functional simulator that mocks our kernel-space driver, allowing the software team to lower operations ahead of hardware teams.

Skills & Experience

5+ years of experience in software engineering with a focus on C/C++ programming. Extensive experience in compilers, low-level programming, and optimisation techniques. Practical experience applying machine learning in high-performance computing contexts. Strong problem-solving skills and the ability to think critically and creatively. Experience in high-pace, dynamic environments. Bachelor's degree in computer science, electrical engineering, telecoms engineering, mathematics, or a related field. Excellent communication skills, with the ability to collaborate effectively with cross-functional teams.

Please note that some of the benefits listed below will not apply to this contract position.

Compensation & Benefits

Competitive salary and stock options, you're not just part of the journey, you will own a piece of it. Work from our HQ in King's Cross, right in the middle of London's buzzing AI scene. Live within 45 minutes of the office? Perfect. Live within 20 minutes? We'll add an extra

24,000 a year

to your salary. We offer visa sponsorship and full relocation support (UK and abroad), through a dedicated third-party provider who are on hand to make your move to London as seamless as possible. Full BUPA healthcare and dental cover, medical history disregarded. High-spec tech for everyone - M4 Macs as standard, M4 Pros for Engineers. Sony noise-cancelling headphones and ergonomic setups to keep you comfortable and focused. Personal company card to spend on tools that help you do your job - like ChatGPT Pro or anything else that boosts your workflow. Healthy, chef-cooked dinners in the office every night, with something for every diet and tastebud. Monthly off-site team socials. 25 days of paid holiday, plus all the UK bank holidays. Access to our in-house 3D printer for personal or work projects. Cycle2work scheme. Need a caffeine fix? We've got you covered with a tab at our favourite local coffee shop. We offer a pension plan and salary sacrifice options.

We're building fast and that includes our benefits. More exciting additions are coming soon for the Flux crew.

If you are passionate about pushing the boundaries of what's possible in AI and thrive in a high-energy, fast-paced environment, we want to hear from you. Apply now to join Flux and be a key player in shaping the future of computing.