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▶ 33:00 · AI Agents · RL on production environments is essential for long-horizon agent capabilities and tool use
episode briefing
Sequoia Capital

How Cursor Trained Composer on Fireworks: Distributed Infrastructure for High-Performance RL

2026-05-26 · 3 company · 4 thematic
sentiment
2 bull0 bear1 neu
speakers
federico

Leads research on Cursor's agentic coding model Composer 2, focusing on model training strategy, RL methodology, and specialization for software engineering within the Cursor environment.

dima

Spent months embedded at Cursor building the distributed inference infrastructure for Composer 2's large-scale RL training, including global cluster orchestration, custom kernels, and weight synchronization systems.

episode shorts · 6

Cursor | Why Online RL Is Just the Cherry on Top

Cursor | The Hidden Bug in Every Large-Scale RL Run

How Cursor Ships a 1TB Model Across the World Mid-Training

Cursor | Does Specializing a Model Break The Bitter Lesson?

Why Cursor Skipped Pre-Training (For Now)

Why Cursor Built Its Own Model (It's Not About Coding)

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