# Heddle > Version control for agent work: an open-source CLI that runs inside your Git repo, records what AI agents change, merges what it safely can, and exports back byte-identical. Sley is the native Rust Git engine underneath it. ## What Heddle and Sley are - Heddle is an open-source command-line tool that layers over a normal Git repository to track and review the work AI agents do, then writes back to Git byte-identical. - Sley is the native Rust Git engine under Heddle: a from-scratch, Git-compatible implementation that replaces shelling out to the git binary. It is the substrate Heddle's speed and portability rest on. ## Positioning - Sley is a native, Git-compatible engine, not a wrapper around the git binary. Every included result is validated cell by cell against real Git. ## Install ``` brew install --cask HeddleCo/tap/heddle ``` ## Links - [Sley to Git parity report](https://heddle.sh/sley-parity) - [Documentation](https://heddle.sh/docs) - [Sley on GitHub](https://github.com/HeddleCo/sley) - [Heddle on GitHub](https://github.com/HeddleCo/heddle) - [Homepage](https://heddle.sh/)