How it works

1. cx locates your global @anthropic-ai/claude-code/cli.js
2. Parses the ~4MB minified bundle into an AST with acorn
3. Each enabled patch finds its target via structural queries and splices in changes
4. The patched source is cached, so subsequent launches are instant
5. cx spawns Node on the cached bundle with your original arguments

Patches are pure AST transforms. They don't monkey-patch at runtime, don't wrap modules, and don't touch the original file on disk.

Caching

The patched bundle is cached keyed by:

• Claude Code version (from its package.json)
• cx version
• The set of enabled patches

A new cache entry is built whenever any of those change. The cache lives under your user config directory, so multiple projects share the same patched bundle.

Authoring patches

See CONTRIBUTING.md in the repo for the patch-authoring guide. Every patch lives in src/patches/ as a single file exporting a Patch object with an apply(ctx) function that operates on the AST.