App Model

A zero-native app provides a name, a WebView source, and optional lifecycle callbacks. The runtime owns the event loop, windows, and native services; the platform owns the web engine.

The App struct

All callback fields are optional. A minimal app only needs context, name, and source.

WebViewSource

Three constructors for specifying what the WebView loads:

• .html(content) -- inline HTML string, served as zero://inline
• .url(address) -- load a remote or local URL
• .assets(options) -- serve a local file tree through a custom origin

The assets constructor takes a WebViewAssetSource:

.source = zero_native.WebViewSource.assets(.{
    .root_path = "dist",
    .entry = "index.html",      // default
    .origin = "zero://app",     // default
    .spa_fallback = true,       // default
}),

Lifecycle events

The runtime dispatches LifecycleEvent values through your event_fn:

• start -- the app has started and the initial source is loaded
• frame -- a frame has been requested (for animations or state updates)
• stop -- the app is shutting down

The runner pattern

The generated src/runner.zig wires the runtime with platform services:

1. Selects the platform (macOS, Linux, or null for headless tests)
2. Sets up trace sinks (stdout + file) via FanoutTraceSink
3. Installs panic capture so crashes write last-panic.txt
4. Initializes window state persistence from windows.zon
5. Creates the Runtime with all options and calls runtime.run(app)

var runtime = zero_native.Runtime.init(.{
    .platform = my_platform,
    .trace_sink = fanout.sink(),
    .bridge = my_app.bridge(),
    .builtin_bridge = .{ .enabled = true, .commands = &builtin_policies },
    .security = .{
        .permissions = &app_permissions,
        .navigation = .{ .allowed_origins = &.{ "zero://app" } },
    },
    .js_window_api = true,
    .window_state_store = state_store,
    .automation = if (build_options.automation) automation_server else null,
});
try runtime.run(my_app.app());

RuntimeOptions

Runtime methods