Modelling Engineer (Mid-Staff)

La Fosse Associates; London; On-site; GBP 70,000 - 90,000; Full time

Job summary

A technology company in London is seeking a Senior Performance Modelling Engineer to lead the design of analytical models for optical computing. This role involves collaboration with cross-functional teams and developing simulators for performance analysis. Candidates should have over 5 years of experience with a strong background in C++ and Python and a deep understanding of computer architecture. This is a unique opportunity in the rapidly evolving field of AI.

Qualifications

• 5+ years of experience building performance or power models for CPUs, GPUs, ASICs, or custom accelerators.
• Proficiency in C++ and Python, with experience in developing simulators.
• Strong understanding of computer architecture fundamentals.

Responsibilities

• Lead and deliver critical projects.
• Collaborate with hardware, compiler, and ML framework teams.
• Develop architectural and cycle-accurate simulators.

Skills

C++

Python

Machine learning frameworks

Data visualization

RTL/schematics interpretation

Education

Bachelor’s degree in relevant field

Master’s or PhD in Electrical Engineering, Computer Science, Physics, Applied Math

Tools

gem5

SystemC

Job description

Build the Future of AI with Optical Compute
We’re pioneering optical processors to train and run inference on large-scale AI models. Join a team of highly motivated and skilled engineers dedicated to rapid innovation and high-impact outcomes.

The Role: Senior Performance Modelling Engineer

We’re looking for a Senior Performance Modelling Engineer to design and own the analytical and simulation models that guide the evolution of our Optical TPU (OTPU) architecture and software. You will be instrumental in building functional and high-fidelity, cycle-accurate models of our optical compute system.

This is a high-leverage role that sits at the intersection of hardware design, software tooling, and machine learning workloads—ideal for engineers who thrive on data-driven decisions, rapid iteration, and solving complex performance challenges.

Key Responsibilities

• End-to-End Ownership: Lead and deliver critical projects that enable major technical and business milestones.

• Cross-Functional Collaboration: Work closely with hardware, compiler, and ML framework teams to ensure performance models are both accurate and actionable.

• Simulator Development:

  • Build and maintain a functional simulator of the OTPU pipeline and subsystems.

  • Develop architectural and cycle-accurate simulators to identify bottlenecks and optimize throughput, latency, and utilization.

• Benchmarking & Bottleneck Analysis: Instrument LLMs, diffusion models, and graph workloads to generate detailed traces for deep performance analysis.

• Design-Space Exploration: Run extensive parameter sweeps to explore architectural tradeoffs, and deliver clear, quantitative insights that guide our hardware, software, and optical designs.

• Tooling & Automation: Create robust Python/C++ tools for trace parsing, statistical analysis, and visualization. Integrate models into CI pipelines for automated performance regression testing.

Required Skills & Experience

• 5+ years of experience building performance or power models for CPUs, GPUs, ASICs, or custom accelerators.

• Proficiency in C++ and Python, with hands-on experience in developing discrete-event or cycle-accurate simulators (e.g., gem5, SystemC, or custom tools).

• Strong understanding of computer architecture fundamentals: memory systems, interconnects, queuing theory, Amdahl’s and Gustafson’s laws.

• Familiarity with machine learning workloads and frameworks like PyTorch, TensorFlow, or JAX.

• Ability to interpret RTL/schematics and discuss micro-architectural trade-offs with hardware engineers.

• Excellent data visualization and communication skills — capable of distilling millions of simulation samples into a single, decisive insight.

Preferred Qualifications

• Advanced degree (Master’s or PhD) in Electrical Engineering, Computer Science, Physics, Applied Math, or a related field.

• Open-source or personal projects involving simulators, ML kernels, or performance analysis.

This role offers a unique opportunity to shape the direction of optical compute at a foundational level. If you’re excited to work at the cutting edge of hardware, software, and AI, we’d love to hear from you.