0diff
AI code change detection
Real-time code modification tracking for the multi-agent era. Single Rust binary. Detects Claude, Cursor, Copilot, Windsurf, Devin. JSON-lines audit trail. MIT licensed.
Building 0diff
Why We Built a Code Change Tracker for the AI Agent Era
In 2026, Claude, Copilot, Cursor, and Devin all modify code -- but nobody tracks who changed what. We built 0diff to solve AI agent attribution.
Real-Time File Watching and Diff Computation in Rust
A synchronous event loop with notify, in-memory file caching, the similar crate for structured diffs, and a whitespace filter -- the core of 0diff in 626 lines of Rust.
Detecting AI Agents in Your Codebase
A 3-tier detection hierarchy: Co-Authored-By commit trailers, environment variables (CLAUDE_CODE, CURSOR_SESSION), and TTY heuristics for identifying AI-generated code changes.
From 5 Agents to Production: Shipping 0diff in 20 Minutes
The full story: 5 parallel agents built 0diff in 45 minutes (2,356 lines, 44 tests), then a 20-minute polish session made it production-ready.