LLM Research Scientist (Pre-training & Post-Training)
Undisclosed employer
Compensation
$100-$120/hr
Description
We're looking for experienced machine learning researchers with hands-on experience training and improving language models end-to-end. You'll work on well-scoped empirical open-ended LLM research problems.
Responsibilities
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Train transformer-based language models from scratch and fine-tune open-weight models.
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Get the most out of limited data and compute.
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Construct training corpora from raw web-scale sources.
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Build post-training pipelines.
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Diagnose and resolve training issues.
Requirements
We are looking for candidates with strong expertise in one or more of the following areas:
Foundation Model Pre-training
Experience with:
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Training transformer-based language models from scratch, end-to-end.
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Data- and compute-constrained regimes: allocating a fixed budget across model size, tokens, and epochs.
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Diagnosing optimisation failures, convergence issues, and training instabilities.
Pre-training Data
Experience with:
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Corpus construction from raw web crawls and other large unfiltered sources.
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Data filtering, deduplication, quality classification, and mixture/ordering optimisation.
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Measuring data interventions rigorously.
LLM Post-Training
Hands-on experience with one or more of:
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Supervised fine-tuning, including building your own datasets via synthetic generation, noisy or weak supervision, and rejection sampling.
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Preference optimisation (DPO, RLHF, RLAIF) and reward modelling / human-preference prediction.
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Alignment fine-tuning: shaping refusal behaviour, truthfulness, and unbiased reasoning while preserving general capability.
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Fine-tuning for narrow, verifiable domains (math, code, games, structured prediction) where outputs can be checked programmatically.
Additional Areas of Interest
Experience in any of the following is a plus:
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Scaling laws and training-efficiency research.
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Curriculum learning and data ordering.
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LLM evaluation: benchmark construction, contamination control, statistically sound comparisons.
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Reinforcement learning for language models.
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Model alignment and AI safety.
General Qualifications
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3+ years of machine learning research experience (PhD research counts toward this requirement).
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Strong experience with PyTorch, JAX, TensorFlow, or similar ML frameworks.
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Degree from a top-100 university, experience at a FAANG or comparable AI company, or an equivalent research track record through publications or impactful open-source contributions.
Why Join
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Work on cutting-edge foundation model research.
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Collaborate with leading AI researchers on challenging, high-impact projects.
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Flexible, project-based work with competitive compensation.
- Commitment
- Hourly
Skills & categories
- Posted
- Jul 8, 2026
- Slots remaining
- 5
- First seen
- Jul 8, 2026
- Last seen
- Jul 9, 2026