Machine Learning Engineer, Platform

About the role

Brain Co. builds AI-native operating systems for large, regulated institutions, including Atlas, a proprietary platform with a foundation model for construction documents, extraction agents, a unified eval system and model routing. As a Machine Learning Engineer on Platform, you will build the core ML capabilities that every product relies on, owning each capability end-to-end from the immediate need to the abstraction serving many pods.

Key responsibilities

• Turn pod needs into platform capabilities: find the general capability inside a specific request without over-abstracting before the pattern is proven.
• Own capabilities end-to-end, with no handoff, and measure success by the velocity of internal teams.
• Build document extraction, financial reporting and market data agents, and the foundation model for construction documents.
• Implement model routing so the right model is used at the right cost and latency, and build a unified eval system across use cases.
• Solve composite AI systems and credit assignment: identify which component fails when a pipeline of vision models, VLM reasoning and rule engines goes wrong.
• Build the machinery of continuous improvement: capture production corrections, triage failures to the responsible component and feed them back into retraining and safe redeployment.

Required profile

• Deep understanding of how machine learning works, beyond the tooling: loss functions, generalization under distribution shift, and why evaluation matters.
• Experience at the edge of modern AI, with instincts for prompting, fine-tuning, tool use and reasoning with LLMs and agentic systems.
• Ability to judge when a fine-tuned segmentation model beats a VLM, when a rule engine beats both, and how to combine them.
• Platform instinct: spotting general capabilities across teams and knowing when generalizing is premature.
• Energetic about building things that have never existed, with problems, data and definitions of success to be invented.

What we offer

• Annual base salary range of $190,000 - $325,000, depending on skills, scope and experience.
• Competitive compensation backed by meaningful equity.
• Country-specific benefits.