Good Start Labs
Machine Learning Engineer
$165K–$250K
Remote (US & Canada) · Full-time · Posted Oct 30, 2026
About the job
Build production systems that turn live games into scalable reinforcement-learning environments, training data, and agent infrastructure.
What you'll do
- Design and scale RL environments and high-speed game engines for real games.
- Build LLM agent harnesses, gameplay data pipelines, and production agent infrastructure.
- Ship public leaderboards and benchmarks for models and human players.
What they ask for
- Deep Python and systems skills.
- Experience building LLM agent harnesses with tool-use APIs or agent SDKs.
- Exposure to RL, simulation, or environment-building.
- Have shipped production ML systems end to end, largely alone.
Pay
$165K-$250K USD base salary
Tools
Python, RL, LLM, Madrona, PufferLib
AI focus
Build reinforcement-learning environments, LLM agent harnesses, expert agents, and training datasets from live gameplay.
Model-written summary · the original posting is authoritative