View role → : ML Engineer, San Francisco

We are hiring an ML Engineer to join Proteus in San Francisco.

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.

Location: San Francisco. Employment type: Full time.

Workplace: On-site.

Start: September 2026. Department: Engineering.

We are looking for someone who

• Has strong ML engineering fundamentals and can take systems from idea to production
• Has experience with post-training — SFT, RL, preference optimization, evals, reward models, or data pipelines
• Operates with a high degree of autonomy
• Ideally knows biology, although curiosity and the ability to learn quickly matter more
• Wants to leave the world better than they found it

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

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. and work in person from their Fort Mason campus.