Principal Research Engineer Post Training Jobs in San Francisco, CA

About the Role This role is responsible for building and strengthening the engineering foundations that our post-training research teams depend

As a Research Scientist working on Safety Post-Training you will develop and apply post-training methods and interpretability techniques to make frontier

About the Role As a Research Engineer / Scientist, you will research and develop improvements to our models.

As a Research Engineer on our Post-Training team, you'll train our base models through the complete post-training stack to deliver the production Claude models that

and post-training efforts.

You’ll work closely with researchers and engineers across post-training and the broader research organization.

About Hedra Hedra is a research and infrastructure lab advancing post-training and inference for multimodal and physical AI.

We’re hiring a Founding ML Research Engineer to work work through the full stack across data, pre-training, post-training & evals for training Generalist

Research Engineer Greptile is an AI code reviewer that catches bugs and anti-patterns in pull requests with complete context of the codebase.

We’re looking for the best research, engineering, product, and operations minds to join us on our mission to push the frontier of audio AI.

Underneath that is the most powerful engine you could ask for, which has been used to post-train multi-100B language parameter models on TPU, post-train robotics

We are looking for Research Scientists and Research Engineers with expertise in LLM post-training (SFT, RLHF, reward modeling).

across post-training.

Our work spans post-training open-weight models for specialized capabilities and pioneering new approaches to voice AI, turning research breakthroughs into reliable