Brain Co.
Machine Learning Engineer, Platform
New York City, NY · Full-time · Posted Sep 30, 2026
About the job
Build and operate shared machine-learning platform capabilities—including document extraction, foundation models, evaluation, model routing, and continuous improvement—for AI systems used by regulated institutions.
What you'll do
- Turn project-pod needs into reusable platform capabilities and own them through production.
- Develop and improve shared ML and agent capabilities, including document extraction, model routing, evaluation, and feedback-driven retraining.
- Engineer production systems for accuracy, latency, cost, and reliability, and support project pods and relevant domain experts.
What they ask for
- Strong understanding of machine-learning fundamentals, including loss functions, generalization, distribution shift, and evaluation.
- Practical expertise with modern AI, including LLMs and agentic systems, prompting, fine-tuning, tool use, and reasoning.
- Ability to combine models and rule engines into accurate systems and assess when each approach is appropriate.
- Platform-oriented judgment: identify reusable capabilities, avoid premature abstraction, and treat internal teams as customers.
Tools
LLMs, RL fine-tuning, VLM
AI focus
Build shared ML platform capabilities for institutional AI, including a construction-document foundation model, extraction agents, unified evaluation, model routing, composite AI systems, and automated continuous improvement.
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