About Crux
The Problem
Every AI coding tool locks your intelligence into their ecosystem. You build up context in Cursor, you lose it when you try Claude Code. You accumulate knowledge in Claude Code, it doesn't transfer to Aider. Your corrections, your learned patterns, your project context — all trapped in vendor-specific directories that die when you switch tools.
The Solution
Crux is the .git for AI coding intelligence. It travels with you, no matter what tool you use.
Your corrections, your knowledge, your session state — all stored in .crux/. One directory. Works with every tool. Switches seamlessly.
How It Works
~/.crux/ # User-level: modes, knowledge, preferences
modes/ # 24 specialized modes
knowledge/ # Accumulated learnings
.crux/ # Project-level: context, corrections, sessions
corrections/ # What the AI got wrong and how you fixed it
knowledge/ # Project-specific patterns
sessions/ # State that persists across tools
context/ # Project context (auto-generated)
The Crux MCP server is a single 6.6MB Rust binary exposing 66 tools via the Model Context Protocol. Zero runtime dependencies. One binary, every tool connects.
The Philosophy
Infrastructure beats prompts. Instead of telling the AI what to remember, Crux builds the infrastructure that makes forgetting impossible.
Your intelligence, your control. The .crux/ directory is plain files you can read, edit, and version control. No vendor lock-in. No cloud dependency.
Corrections compound. Every time you fix an AI mistake, Crux captures it. Next time, the AI knows better. Across every tool.
Who Built This
Crux is built by a solo developer who uses AI coding tools every day. Every feature exists because it solved a real problem. Every architectural decision comes from actual usage.
The project is open source. The code is the documentation.
What's Next
- Get started — Download a single binary, adopt your project
- See the 66 tools — Complete MCP tool reference
- See the modes — 24 specialized modes for different work
- Read the blog — Build-in-public updates
- View on GitHub — MIT licensed, open source