Machine Learning Expert
Role details
To qualify you must work as an ML research engineer, research scientist or applied scientist, and have personally trained, fine-tuned or optimized models in PyTorch or JAX.
What you'll do
- Come up with ideas for hard machine learning engineering tasks ("plans") for a long-horizon AI research project with a leading AI lab
- Design tasks hard enough to stump frontier models: a strong task is solved in no more than 2 out of 8 attempts
- Lean toward inference, evaluation and systems work rather than heavy model training. About half of the tasks run on GPU and half are CPU-only
- Explain clearly why each problem is hard for a frontier model
- You mainly contribute ideas. You do not need to build or review the tasks yourself
Must-haves
- Current or recent role as an ML research engineer, research scientist or applied scientist
- Hands-on experience personally training, fine-tuning or optimizing models in PyTorch or JAX
- Deep knowledge of at least one of these areas:
- LLMs: pretraining, alignment, evals
- GPU inference and performance: vLLM, Triton, CUDA, profiling
- Reinforcement learning (RL)
- Scientific ML: weather and climate, physics, biology
- Able to explain why a problem is hard for a frontier model
Nice-to-haves
- Experience writing benchmark or evaluation questions (a big plus)
- PhD in ML, CS or physics, or an MSc plus strong research output
- Publications
- Prior Mercor contracts with strong performance
Not a fit
- Software or full-stack engineers whose AI experience is mainly building LangChain or RAG applications
- Backgrounds limited to AI trainer, rater or annotator work
From the Mercor posting.
Applying on Mercor
What happens after you click
- The link opens this role on Mercor. Sign up and apply from there.
- Upload a resume, complete the assessments the role asks for and verify your work authorisation.
- An AI interview of about 20 minutes. The confirmation screen then shows the expected timeline for that role.
- If Mercor hires you, you are paid weekly, on the Wednesday after each work week, via Stripe. Mercor says first payouts are held for 7 days.
- Remote — open to United States, Canada, United Kingdom, Ireland, Australia, New Zealand, Germany, France, Netherlands, Belgium, Austria, Switzerland, Denmark, Sweden, Norway, Finland, Iceland, Italy, Spain, Portugal, Greece, Luxembourg, Malta, Cyprus, Liechtenstein and Monaco.
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We read this listing on Mercor on 20 Oct 2026 and checked it again on 20 Oct 2026. We clean its formatting for readability and safety. View on Mercor
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