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For Companies At a Glance
- Tasks: Create and own analytical models to drive optical processor architecture and software evolution.
- Company: Join Flux Computing, a leader in optical processors for AI innovation.
- Benefits: Competitive salary, stock options, full healthcare, and flexible work arrangements.
- Why this job: Make a real impact in AI by shaping the future of optical computing.
- Qualifications: 5+ years in performance modelling with strong C++ and Python skills.
- Other info: Enjoy a vibrant office culture with chef-cooked meals and monthly team socials.
The predicted salary is between 130000 - 200000 £ per year.
Flux Computing designs and manufactures optical processors to train and run inference on large AI models. Join us to be part of a highly motivated and skilled team that thrives on delivering impact and innovation at speed.
The Role
We are searching for a Senior Performance Modelling Engineer to create and own the analytical and simulation models that steer OTPU architecture and software evolution. You will build functional simulators as well as high-fidelity, cycle-accurate models of our optical compute system. This role is critical to explore "what-if" design spaces, and deliver insights that directly influence our software, hardware, and optical roadmaps. This role sits at the crossroads of hardware architecture, software tooling and machine-learning workload analysis, perfect for an engineer who loves data-driven decision-making and fast iteration.
Responsibilities
- Project Ownership: Own and deliver projects on your team's roadmap that unlock key high-impact technical and business milestones that drive the success of Flux.
- Collaboration: Work shoulder-to-shoulder with hardware, compiler and ML framework teams to ensure models reflect reality and reality meets performance goals.
- Functional Simulator: Design, build, and maintain a functional simulator of the OPTU subsystem and full pipeline.
- Performance Simulator: Design and maintain architectural & cycle-accurate models of the OPTU subsystems and pipeline. Identify throughput, latency and utilisation hot-spots; propose architectural, or scheduling fixes.
- Workload Analysis & Bottleneck Hunting: Instrument benchmarks (LLMs, diffusion, graph workloads) to collect detailed traces.
- Design-Space Exploration: Run massive parameter sweeps with your functional and to understand tradeoffs and guide the software, hardware, and optical teams. Package results into clear, quantitative analyses and design recommendations.
- Tooling & Automation: Develop Python/C++ tooling for trace parsing, statistical analysis and visualisation. Integrate models into CI so that every RTL commit gets a performance smoke test.
Skills & Experience
- 5+ years building performance or power models for CPUs, GPUs, ASICs, or accelerators.
- Strong coding ability in C++ and Python; experience with discrete-event or cycle-accurate simulators (e.g., gem5, SystemC, custom in-house).
- Solid grasp of computer-architecture fundamentals: memory systems, interconnects, queuing theory, Amdahl/Gustafson analysis.
- Familiarity with machine-learning workloads and common frameworks (PyTorch, TensorFlow, JAX).
- Comfort reading RTL or schematics and discussing micro-architectural trade-offs with hardware designers.
- Excellent data-visualisation and communication skills: able to turn millions of simulation samples into one decisive slide.
- Bachelor's+ in EE, CS, Physics, Applied Maths or related; advanced degree preferred but not required.
- Personal or open-source projects in simulators, ML kernels, or performance analysis are a significant plus.
Compensation & Benefits
- £153,000 – £187,000 annual salary, depending on experience, skills, and location.
- Competitive stock options, you are 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 will add an extra location bonus 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 have got you covered with a tab at our favourite local coffee shop.
- We offer a pension plan and salary sacrifice options.
AI Senior Performance Modeller in London employer: Flux Computing
Contact Detail:
Flux Computing Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land AI Senior Performance Modeller in London
✨Tip Number 1
Network like a pro! Reach out to people in the industry, attend meetups, and connect with current employees at Flux Computing. A friendly chat can sometimes lead to opportunities that aren’t even advertised.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your projects, especially those related to performance modelling or machine learning. This gives you a chance to demonstrate your expertise beyond just a CV.
✨Tip Number 3
Prepare for interviews by diving deep into the tech stack used at Flux. Brush up on your C++ and Python skills, and be ready to discuss your experience with simulators and workload analysis. Confidence is key!
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen. Plus, it shows you’re genuinely interested in being part of the Flux team.
We think you need these skills to ace AI Senior Performance Modeller in London
Some tips for your application 🫡
Show Your Passion for AI: When writing your application, let us see your enthusiasm for AI and performance modelling. Share any personal projects or experiences that highlight your skills and passion for the field.
Tailor Your CV: Make sure your CV is tailored to the role of Senior Performance Modelling Engineer. Highlight relevant experience with performance models, coding in C++, Python, and any work with machine-learning frameworks.
Be Clear and Concise: In your cover letter, be clear and concise about why you’re a great fit for the role. Use specific examples to demonstrate your skills and how they align with our needs at Flux Computing.
Apply Through Our Website: We encourage you to apply through our website for a smoother process. It helps us keep track of applications and ensures you don’t miss out on any important updates from us!
How to prepare for a job interview at Flux Computing
✨Know Your Models Inside Out
Make sure you’re well-versed in the performance and power models relevant to CPUs, GPUs, and ASICs. Be ready to discuss your experience with cycle-accurate simulators like gem5 or SystemC, as well as any personal projects that showcase your skills.
✨Showcase Your Collaboration Skills
Since this role involves working closely with hardware, compiler, and ML framework teams, prepare examples of past collaborations. Highlight how you’ve successfully communicated complex ideas and ensured alignment across different teams.
✨Prepare for Technical Questions
Brush up on computer architecture fundamentals, including memory systems and queuing theory. Expect questions that test your understanding of Amdahl/Gustafson analysis and be ready to discuss how these concepts apply to real-world scenarios.
✨Visualise Your Data
You’ll need to turn complex simulation data into clear insights. Prepare a few examples of how you’ve visualised data in the past, and be ready to explain your thought process behind creating impactful presentations or reports.
