Performance Modelling Engineer

OLIX•San Francisco, CA

1d•$233,000 - $314,000

About The Position

AI is growing faster than any technology in history and the explosion in demand has created a massive infrastructure gap; we can no longer build chips or power stations fast enough to keep up. The industry is still leaning on a ten-year-old hardware blueprint that has reached its limit. A new paradigm that is faster and more efficient will be the biggest economic opportunity of the next century and create the most important company of the next decade. OLIX is building this next paradigm; the Optical Tensor Processing Unit (OTPU) achieves performance and energy efficiency that is impossible to match from existing chips. We’re searching for a Senior Performance Modelling Engineer (The Bay Area) 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.

Requirements

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.

Nice To Haves

Personal or open-source projects in simulators, ML kernels, or performance analysis are a significant plus.

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 Olix.
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.

Benefits

Competitive Salary: $233,000 - $314,000 annually, commensurate with your experience, skills, and location.
Equity & Ownership: Meaningful stock options. You’re not just joining the mission; you’re owning a piece of it.
Proximity Bonus: We value your time. To minimise your commute and maximise your life, we offer a $36k annual Living-Local Bonus if your residence is within 20 minutes of the office.
Time Off: 33 days of paid time off (PTO), including US federal holidays.
Healthcare Coverage: Multiple high-quality medical plan options, including family coverage.
Health Savings Account: A high-deductible medical option with a company-funded health savings account (HSA).
Dental & Vision: Dental and vision coverage.
Additional Coverage: Life insurance, plus short- and long-term disability.
Wellbeing Support: Mental health resources, fertility and family-building support.
Commuter Benefits: Pre-tax commuter and parking benefits.
401(k): Access to a 401(k) retirement plan with a 4% employer match, with both traditional and Roth contribution options. Employees also have access to a dedicated financial advisor to support portfolio selection and long-term planning.
M4 Macs come as standard, with M4 Pro upgrades for our engineering team. We will provide whatever you need to do your best work.
High-spec noise-cancelling headphones and a fully ergonomic workstation designed for deep focus.
Rapid Prototyping: Access to our high-performance 3D printing lab for work, experimentation, and personal creative projects.
Chef-prepared meals: if you need to work late.
Visa Sponsorship: We hire the best in the world. We offer full UK and international visa sponsorship.
Seamless Relocation: Whether you’re moving across the country or across the globe, our dedicated relocation partner provides funding and concierge support to get you settled.