# Compaction

- [Cursor Composer 2: The Model That Learns to Forget — and Sparked a Controversy](https://sdd.sh/2026/03/cursor-composer-2-the-model-that-learns-to-forget-and-sparked-a-controversy.md): Cursor's new coding model beats Claude Opus 4.6 on key benchmarks — but the real story is a training breakthrough called compaction-in-the-loop RL, and a transparency controversy that revealed Cursor quietly built it on a Chinese open-source model.