Build native iOS, Android, desktop, and web apps in Rust with a fine-grained reactive runtime, Taffy layout, and native Host renderers. No virtual DOM.

---

use whisker::prelude::*;

#[whisker::main]
fn app() -> Element {
    render! {
        Counter
    }
}

#[component]
fn counter() -> Element {
    let count = signal(0);
    render! {
        View(style: css!(
            flex_grow: 1.0,
            display: Display::Flex,
            flex_direction: FlexDirection::Column,
            justify_content: JustifyContent::Center,
            align_items: AlignItems::Center,
            gap: px(12),
            background_color: Color::hex(0x0B0B0F),
        )) {
            Text(
                value: computed(move || format!("Count: {}", count.get())),
                style: css!(color: Color::hex(0xFFFFFF), font_size: px(28)),
            )
            View(
                style: css!(
                    padding: (px(10), px(20)),
                    border_radius: px(10),
                    background_color: Color::hex(0x7C5CFF),
                ),
                on_tap: move |_| count.set(count.get() + 1),
            ) {
                Text(value: "+1", style: css!(color: Color::hex(0xFFFFFF)))
            }
        }
    }
}

_{Edit, save — the running app hot-reloads in under a second, with state intact.}

Get started

cargo install whisker-cli
rustup target add aarch64-apple-ios-sim   # iOS Simulator on Apple silicon
whisker new my-app && cd my-app
whisker run ios          # also: android, web, desktop

Each platform needs its Rust target: aarch64-linux-android for Android (plus the Android SDK, NDK, and a JDK), wasm32-unknown-unknown for Web, and x86_64-apple-ios instead for the iOS Simulator on an Intel Mac. Run whisker doctor to see what is missing, or follow Installation.

whisker run watches your source and hot-patches the running app in under a second, without a restart. Components you didn't edit keep their state.

App metadata and platform settings live in whisker.rs. whisker run and whisker build generate the native projects from it under gen/, so there is nothing else to run. Add plugins with cargo add and configure them there.

Documentation

Everything — installation, core concepts, guides, and the full API reference — lives at whisker.rs/docs.

Status

Pre-alpha. The retained Rust runtime, typed styling, Host renderers, modules, routing, and hot reload work across iOS, Android, Web, and Desktop. APIs may still change before 1.0.

License

Licensed under either of Apache-2.0 or MIT at your option.