Job Description

Ready to lead the development of a foundation model that powers the next generation of Agentic AI?

This is a hands-on leadership role where you’ll train models from scratch, make the key architectural decisions, and grow your own team. The work will build a Foundation model underpinning AI systems that think, reason, and act in mission-critical environments.

You’ll join a well-backed company founded by an entrepreneur with a previous billion-dollar exit, already partnering with Fortune 100 and 500 clients. Their latest funding round is being channelled directly into compute and team buildout — a substantial commitment to creating truly differentiated AI technology, powered by the foundation model you’ll help design and train.

The challenge: build reasoning-capable foundation model to power Agents, another team in the company will fine-tune and adapt from specific industry use-cases and clients. Your team will work at scale, combining pre-training and post-training approaches while ensuring models meet regulated industry requirements. This is about more than just building models — it’s about creating infrastructure, teams, and frameworks that define the future of AI in high-stakes settings.

Your focus will include leading pre-training and post-training of foundation models, architecting reasoning-capable LLMs, scaling a 15–20 person research and engineering team over 12 months, and integrating models into domain-specific applications.

You should bring:

• Staff/Principal-level experience with hands-on model training.

• Deep expertise in pre-training or post-training (ideally both).

• Track record of driving impactful projects to completion.

• Strong understanding of LLM architectures and large-scale training.

• Experience leading complex technical initiatives across teams.

Nice to have: experience in regulated/safety-critical AI, reasoning or planning architectures, open-source model development, or prior technical leadership.

Package: $350k base (negotiable) + substantial stock, healthcare, 401k, 20 vacation days, and flexible working.

You must be based in the SF Bay Area. US citizens and green card holders only.

This is an opportunity to lead foundation model development with the resources, autonomy, and backing to deliver groundbreaking technology.

All applicants will receive a response.