Cursor ditches VS Code, but not everyone is happy...

Fireship breaks down Cursor 3.0’s full rewrite in Rust, its undisclosed Kimi K2-based model, and the shift to multi-agent swarm coding.

• Cursor 3.0 is no longer a VS Code fork — fully rewritten in Rust and TypeScript from scratch.
• Composer 2 was marketed as an in-house frontier model beating Claude Opus 4.6, but is actually based on Moonshot’s Kimi K2 with reinforcement learning.
• Cursor only disclosed the Kimi K2 basis after a user found the model ID in metadata and posted it on Twitter; Cursor later apologized.
• Kimi K2 itself has been accused of training on Claude outputs — it occasionally identifies itself as Claude.
• Cursor 3.0 lets users run parallel agents across multiple repos, remote SSH machines, and cloud simultaneously from one interface.
• The new UI is agent-management-first: built-in browser, git history, terminal, and file explorer are secondary to agent orchestration.
• 13,000 lines of code were generated in minutes in the demo, with a yellow/blue dot system signaling when human input is needed.

2026-04-06 · Watch on YouTube