Research Engineer - Midtraining

Posted:
8/12/2026, 1:01:42 AM

Location(s):
California, United States ⋅ Menlo Park, California, United States

Experience Level(s):
Junior ⋅ Mid Level ⋅ Senior

Field(s):
Data & Analytics

Workplace Type:
On-site

Pay:
$250k–$350k/yr

We're an AI and physical sciences company building state-of-the-art models to accelerate breakthroughs across materials, energy, and beyond. Backed by world-class investors and growing rapidly, we operate at the pace the frontier requires. Our team brings deep expertise, genuine ownership, and a drive to push the boundaries of what's scientifically possible.

About the Role

We're training frontier models to develop deep scientific knowledge and reasoning for scientific discovery. As a Midtraining Research Engineer, you'll take base models and improve their scientific reasoning: curating and generating data, building evals, and running large-scale training experiments. Your work will also lay the groundwork for our pre-training efforts down the line.

What You'll Do

  • Identify, process, and curate novel sources of scientific data for large-scale model training.

  • Generate high-quality synthetic data to fill gaps in scientific knowledge and reasoning.

  • Build evaluations that correlate with downstream scientific task performance, working closely with RL researchers, physicists, and chemists.

  • Develop and apply techniques such as self-distillation and on-policy distillation to improve model capability.

  • Design and run large-scale training experiments, partnering with supercompute engineers to scale efficiently across thousands of GPUs.

  • Build tools for yourself and the team to investigate how data choices shape model intelligence.

You Will Thrive in This Role If You Have

  • Experience training LLMs on curated mixes of trillions of tokens.

  • Experience on a dedicated evals team supporting a large production training run.

  • Hands-on use of self-distillation, on-policy distillation, or similar methods in a real training pipeline.

  • Experience with scaling laws and compute-optimal hyperparameters.

  • Comfort working across data, evals, and training infrastructure.

Especially Strong Candidates May Also Have

  • Experience optimizing throughput and reliability for large-scale distributed training runs.

  • A background in AI for science or training on specialized domain data (e.g., protein, materials, or other scientific datasets).

  • Experience creating evals or synthetic data for non verifiable tasks and tracking performance over live runs.

Mechanics

  • Minimum education: Bachelor's degree or similar experience

  • Location: Menlo Park, CA (Soon: San Francisco, too)

  • Compensation: $250,000–$350,000 + equity

  • Visa sponsorship: Yes, we sponsor visas and will do everything we can to assist in this process.

Periodic Labs

Website: https://periodic.com/

Headquarter Location: San Francisco, California, United States

Employee Count: 11-50

Year Founded: 2025

IPO Status: Private

Last Funding Type: Seed

Industries: Artificial Intelligence (AI) ⋅ Foundational AI ⋅ Generative AI ⋅ Machine Learning

Visa Sponsorship: Sponsors work visas