Research, Post-Training Data San Francisco

Thinking Machines Lab's mission is to empower humanity through advancing collaborative general intelligence. We are building a future where everyone has access to the knowledge and tools to make AI work for their unique needs and goals. We are scientists, engineers, and builders who’ve created some of the most widely used AI products, including ChatGPT and Character.ai, open‑weights models like Mistral, and popular open source projects such as PyTorch, OpenAI Gym, Fairseq, and Segment Anything. About the Role The role of post‑training researchers sits at the core of our roadmap. This is the critical bridge between raw model intelligence and a system that is actually useful, safe, and collaborative for humans. Post‑training data research sits at the intersection of human insight and machine learning. Our work combines human and synthetic data techniques, along with other innovative approaches, to capture the nuances of human behavior and use them to steer models. We research and model the mechanisms that create value for people to explain, predict, and optimise for human preferences, behaviours and satisfaction. Our goal is to turn research ideas into data by scoping well‑run data‑labeling or collection campaigns, and understanding the science behind what makes the data high‑quality and useful to train our models. We also develop and evaluate quantitative metrics that measure the success and impact of our data and training interventions. Beyond execution, we explore new paradigms for human‑AI interaction and scalable oversight, experimenting with how humans can best supervise, guide, and collaborate with models. It’s interdisciplinary work that blends research, data operations, and technical implementation to advance the frontier of aligned, human‑centered AI systems. This role blends fundamental research and practical engineering, as we do not distinguish between the two roles internally. You will be expected to write high‑performance code and read technical reports. It’s an excellent fit for someone who enjoys both deep theoretical exploration and hands‑on experimentation, and who wants to shape the foundations of how AI learns. Note: This is an evergreen role that we keep open on an ongoing basis to express interest in this research area. We receive many applications, and there may not always be an immediate role that aligns perfectly with your experience and skills. Still, we encourage you to apply. We continuously review applications and reach out to applicants as new opportunities open. You are welcome to reapply if you get more experience, but please avoid applying more than once every six months. You may also find that we put up postings for singular roles for separate, project or team specific needs. In those cases, you’re welcome to apply directly in addition to an evergreen role. What You’ll Do Design and execute data collection and synthesis strategies for post‑training by combining human feedback, preference data and synthetic examples to guide model behaviour. Develop pipelines and frameworks for scalable, high‑quality human labeling, model‑assisted labeling and synthetic data generation. Research and model human preferences and behaviour, creating data‑driven methods to improve reasoning, truthfulness and helpfulness. Iterate on evals: post‑training involves a never‑ending loop of defining a set of evaluations, optimizing them, and then realizing your existing evals don’t capture what matters. You’ll be responsible for both making numbers go up and ensuring the numbers are meaningful. Design and evaluate metrics and benchmarks that measure data quality, alignment and the real‑world impact of post‑training interventions. Scale and explore: post‑training will involve a combination of scaling the existing methodologies and developing new ones. Publish and present research that moves the entire community forward. Share code, datasets and insights that accelerate progress across industry and academia. Skills and Qualifications Strong engineering skills, ability to contribute code and debug in complex codebases. Experience with data curation, human feedback or synthetic data generation for large language models or similar systems. Ability to design, run and interpret experiments with scientific rigor and clarity. Proficiency in Python and familiarity with at least one deep learning framework (PyTorch, TensorFlow or JAX). Comfortable with debugging distributed training and writing code that scales. Bachelor’s degree or equivalent experience in Computer Science, Machine Learning, Physics, Mathematics or a related discipline with strong theoretical and empirical grounding. Clarity in communication, ability to explain complex technical concepts in writing. Preferred Qualifications A strong grasp of probability, statistics and ML fundamentals. You can look at experimental data and distinguish between real effects, noise and bugs. Prior experience with RLHF, RLAIF, preference modelling or reward learning for large models. Experience managing or analysing human data collection campaigns or large‑scale annotation workflows. Research or engineering contributions in alignment, data‑centric AI or human‑AI collaboration. Familiarity with synthetic data pipelines, active learning or model‑assisted labeling. PhD in Computer Science, Machine Learning, Physics, Mathematics or a related discipline with strong theoretical and empirical grounding; or equivalent industry research experience. Logistics Location: This role is based in San Francisco, California. Compensation: Depending on background, skills and experience, the expected annual salary range for this position is $350,000 – $475,000 USD. Visa sponsorship: We sponsor visas. While we can’t guarantee success for every candidate or role, if you’re the right fit we’re committed to working through the visa process together. Benefits: Thinking Machines offers generous health, dental and vision benefits, unlimited PTO, paid parental leave and relocation support as needed. As set forth in Thinking Machines’ Equal Employment Opportunity policy, we do not discriminate on the basis of any protected group status under any applicable law. Thinking Machines Lab will consider for employment qualified applicants with criminal histories in a manner consistent with the requirements of the California Fair Chance Act, the San Francisco Fair Chance Ordinance and any other applicable state or local fair‑chance ordinance or law. #J-18808-Ljbffr Thinking Machines Lab Inc.