Proteus Bio

We are hiring an ML Engineer or an AI Engineer to join Proteus in San Francisco/London.

Company Description: We are building a Biological Intelligence Platform for the autonomous discovery of personalised medicine. Our platform reasons over disease targets, designs therapeutic and diagnostic candidates, and continuously learns from experimental results.

P.S: Apply at https://proteusbio.ai/careers/ link your github/something you’re proud of building and why this role actually excites you.

We are looking for an:

ML Engineer — Policy Training

Preferred Experience:

 - PyTorch and Hugging Face: Transformers, TRL, Accelerate

 - SFT / instruction tuning

 - LoRA, QLoRA and PEFT

 - DPO / g-DPO for preference training

 - GRPO / PPO for online reinforcement learning

 - Reward models, rule-based verifiers and outcome-based rewards

 - Tool-use trajectory collection and credit assignment

 - Distributed GPU training: DeepSpeed, FSDP, mixed precision

- Model evaluation, checkpointing and experiment tracking

OR

AI Engineer

Preferred Experience:

 - LLM agents and tool calling

 - LangGraph/stateful workflow orchestration

 - RAG, memory and context engineering

 - Structured outputs and typed tool schemas

 - Agent evaluations, tracing and observability

 - Secure sandboxed code execution

 - Python, FastAPI, async jobs, containers

AND

• Ideally knows biology, although curiosity and the ability to learn quickly matter more
• Wants to leave the world better than they found it

Biology experience is valuable, but not required. We care more about what you have built, how you think, and whether you take ownership than where you went to school.

We are backed by Founders, Inc.

If this sounds like you, tell us about something you have built that you are proud of, and why this problem interests you.

If someone exceptional comes to mind, please send them our way. Pints on us if you land an interview, or if your recommendation does 🍻