# What is gpui? **gpui** is the UI toolkit that the **Zed editor** is built on. - Pure Rust. - GPU-accelerated — it draws everything itself, no HTML, no native widgets. - Cross-platform target (best on macOS; Linux and Windows are catching up). Think of it as: *"What if a Rust crate let you build a native window the same way you build a React component — but the result is a real desktop app, not a browser tab?"* --- ## Why try it - It is **fast**. Zed runs at 120fps on a Mac and feels it. - It is **all Rust**. No JavaScript, no glue layer. - The API feels surprisingly familiar if you have touched web UI before — we will see why on the next slide. --- ## Where to find it - Repo: <https://github.com/zed-industries/zed> (gpui lives under `crates/gpui/`) - Docs: <https://docs.rs/gpui> - The reference app: the Zed editor itself. --- ## A taste ```rust div() .flex() .flex_col() .items_center() .gap_6() .child(div().text_3xl().child("42")) .child(button("+", on_increment)) ``` If that looks suspiciously like Tailwind CSS — good eye. We will get to that in two slides.