LLM Research Scientist (Pre-training & Post-Training)
Software Engineering, Data Science
Sydney, NSW, Australia
Posted on Jul 12, 2026
This is a LLM Research Scientist (Pre-training & Post-Training) role with Mercor based in Sydney, NSW, Australia
== Mercor ==
Role Seniority - mid level, senior
More about the LLM Research Scientist (Pre-training & Post-Training) role at Mercor
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
We are looking for candidates with strong expertise in one or more of the following areas:
Foundation Model Pre-training
Experience With:
Experience With:
Hands-on Experience With One Or More Of:
Experience in any of the following is a plus:
Contract and Payment Terms
🟢 Please consider applying even if you don't meet 100% of what’s outlined 🟢
Key Responsibilities
A Final Note: This is a role with Mercor not with Hatch.
== Mercor ==
Role Seniority - mid level, senior
More about the LLM Research Scientist (Pre-training & Post-Training) role at Mercor
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
- Train transformer-based language models from scratch and fine-tune open-weight models.
- Get the most out of limited data and compute.
- Construct training corpora from raw web-scale sources.
- Build post-training pipelines.
- Diagnose and resolve training issues.
We are looking for candidates with strong expertise in one or more of the following areas:
Foundation Model Pre-training
Experience With:
- Training transformer-based language models from scratch, end-to-end.
- Data- and compute-constrained regimes: allocating a fixed budget across model size, tokens, and epochs.
- Diagnosing optimisation failures, convergence issues, and training instabilities.
Experience With:
- Corpus construction from raw web crawls and other large unfiltered sources.
- Data filtering, deduplication, quality classification, and mixture/ordering optimisation.
- Measuring data interventions rigorously.
Hands-on Experience With One Or More Of:
- Supervised fine-tuning, including building your own datasets via synthetic generation, noisy or weak supervision, and rejection sampling.
- Preference optimisation (DPO, RLHF, RLAIF) and reward modelling / human-preference prediction.
- Alignment fine-tuning: shaping refusal behaviour, truthfulness, and unbiased reasoning while preserving general capability.
- Fine-tuning for narrow, verifiable domains (math, code, games, structured prediction) where outputs can be checked programmatically.
Experience in any of the following is a plus:
- Scaling laws and training-efficiency research.
- Curriculum learning and data ordering.
- LLM evaluation: benchmark construction, contamination control, statistically sound comparisons.
- Reinforcement learning for language models.
- Model alignment and AI safety.
- 3+ years of machine learning research experience (PhD research counts toward this requirement).
- Strong experience with PyTorch, JAX, TensorFlow, or similar ML frameworks.
- 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.
- Work on cutting-edge foundation model research.
- Collaborate with leading AI researchers on challenging, high-impact projects.
- Flexible, project-based work with competitive compensation.
Contract and Payment Terms
- You will be engaged as an independent contractor.
- This is a fully remote role that can be completed on your own schedule.
- Projects can be extended, shortened, or concluded early depending on needs and performance.
- Your work at Mercor will not involve access to confidential or proprietary information from any employer, client, or institution.
- Payments are weekly on Stripe or Wise based on services rendered.
- Please note: We are unable to support H1-B or STEM OPT candidates at this time.
🟢 Please consider applying even if you don't meet 100% of what’s outlined 🟢
Key Responsibilities
- 🔄 Training language models
- 💻 Optimizing data usage
- 🏗️ Building training pipelines
- 🧠 Machine learning research experience
- ⚙️ Experience with ML frameworks
- 📚 Foundation model pre-training
- 📈 Scaling laws and training-efficiency research
- 📊 Curriculum learning and data ordering
- 🔒 Model alignment and AI safety
A Final Note: This is a role with Mercor not with Hatch.