This is bitbar, a library crate which includes helpers for writing BitBar plugins in Rust. BitBar is a system that makes it easy to add menus to the macOS menu bar. There are two apps implementing the BitBar system: SwiftBar and xbar. This crate supports both of them, as well as the discontinued original BitBar app.
Here are some BitBar plugins that use this library:
If you have a BitBar plugin that uses this library, feel free to open a pull request to add it to this list.