Muse Toolkit

MTK is a declarative, retained-mode GUI toolkit for Rust. It pairs an Elm-inspired functional interface with a C-based Flexbox layout engine, native WGPU hardware rendering, and Parley typography.

Warning

Still experimental and under active development. Not recommended for production use.

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Philosophy

• Declarative Views, Retained Elements: Write functional, declarative views (view(&state) -> impl View<State>). MTK retains layout nodes and updates only changed properties via rebuild().
• Primitives Over Monoliths: Focus on flexible, unopinionated primitives rather than a rigid widget set, making it easy to build custom workstation tools, editors, and domain components.
• Accessible Core: The coordinator (Context), layout engine (muse.h), typography metrics, and GPU canvas passes are public so developers can build on top of MTK without fighting the framework.
• Source Introspection: Every widget tracks its call site with #[track_caller] for live in-tree debugging and inspection.

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Use the master branch

# Cargo.toml
mtk-rs = { git = "https://github.com/luxluth/mtk.git", branch = "master" }

Core Technologies

MTK brings together proven technologies from across the systems and graphics ecosystem:

• Layout: muse.h — C-based Flexbox engine with incremental layout passes, aspect-ratio resolution, and scroll clamping.
• Graphics: WGPU — Cross-platform GPU rendering targeting Vulkan, Metal, and DirectX 12.
• Typography: Parley, Swash — Multi-font styling, dynamic font fallback, OpenType ligatures, and inline span geometry.
• Windowing: winit — Native window creation, DPI scaling, and event handling.
• Images: zune-image, resvg — Asynchronous streaming loader (mtk-image-loader) with byte-bounded LRU caching.
• Inspector: Ratatui — Built-in terminal UI layout inspector.
• Clipboard: arboard — Cross-platform clipboard read and write support.

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Quick Start Example

Below is a complete, minimal example that creates a window displaying text:

use mtk::clr;
use mtk::style::{Size, Style};
use mtk::ui::ViewStyleExt;
use mtk::ui::widgets::text;
use mtk::windowing::{Window, WindowAttributes};

fn main() {
    let mut window = Window::with(
        (),
        |_state, _msg: ()| {},
        |_state| {
            text("Hello, MTK!").style(
                Style::new()
                    .bg_color(clr!(white))
                    .padding(10.)
                    .width(Size::Percent(1.))
                    .height(Size::Percent(1.)),
            )
        },
    );

    let attrs = WindowAttributes::new()
        .with_title("Hello MTK")
        .with_size((400, 200).into());

    window.present_with(attrs);
}

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State Management and Lenses

MTK uses unidirectional data flow with typed messages. To decompose large application states into reusable sub-views without cloning, MTK provides Lenses and the Adapter Pattern:

use mtk::Lens;
use mtk::ui::widgets::*;
use mtk::ui::{adapt, ViewAdaptExt, View};

#[derive(Lens)]
struct AppState {
    username: String,
    bio: String,
}

enum AppMsg {
    SetUsername(String),
    SetBio(String),
}

fn view(state: &AppState) -> impl View<AppState, Message = AppMsg> {
    column((
        text("Profile Editor"),
        // Adapt via the standalone helper and derived lens:
        adapt(input_text(), AppState::username, AppMsg::SetUsername),
        // Or adapt via method chaining extension trait:
        text_area().adapt(AppState::bio, AppMsg::SetBio),
    ))
}

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Examples

To run the included widget gallery:

cargo run --example widget_gallery

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Acknowledgments

MTK is inspired by Xilem and borrows architectural concepts for reactive, declarative GUI representation and state adaptation in Rust.