gtkx
Build GTK4 desktop apps with GTKX — React JSX renders as native Linux widgets via Rust FFI. Use when creating Adwaita widgets, styling GTK with CSS-in-JS, or debugging GTKX components.
What this skill does
# GTKX
GTKX renders React components as native GTK4 widgets on Linux: `@gtkx/react` → FFI bridge → GTK4/GLib.
## Project Setup
```bash
npx @gtkx/cli@latest create my-app
# Runs: npm run dev | npm run build | npm test (vitest + Xvfb)
```
Generates `src/app.tsx`, `src/dev.tsx` (HMR), `src/index.tsx`. Entry calls `render(<App />, pkg.gtkx.appId)`.
## Essential Patterns
### Controlled Inputs
Widgets require explicit two-way binding — not React state alone:
```tsx
const [text, setText] = useState("");
<GtkEntry text={text} onChanged={(e) => setText(e.getText())} />;
// GtkSwitch: return true from onStateSet to accept change
```
### Compound Components (Slots)
Use compound components for child positioning — auto-generated from GIR:
```tsx
<AdwToolbarView>
<AdwToolbarView.AddTopBar><AdwHeaderBar /></AdwToolbarView.AddTopBar>
</AdwToolbarView>
<GtkHeaderBar>
<GtkHeaderBar.PackStart><GtkButton iconName="go-previous-symbolic" /></GtkHeaderBar.PackStart>
<GtkHeaderBar.TitleWidget><GtkLabel label="Title" /></GtkHeaderBar.TitleWidget>
</GtkHeaderBar>
```
Common compound components: `AddTopBar`/`AddBottomBar` (ToolbarView), `PackStart`/`PackEnd` (HeaderBar/ActionBar), `StartChild`/`EndChild` (Paned/Flap).
### Adwaita Skeleton
```tsx
<AdwApplicationWindow
title="App"
defaultWidth={800}
defaultHeight={600}
onClose={quit}
>
<AdwToolbarView>
<AdwToolbarView.AddTopBar>
<AdwHeaderBar>
<GtkHeaderBar.PackStart>
<GtkButton iconName="open-menu-symbolic" />
</GtkHeaderBar.PackStart>
<GtkHeaderBar.TitleWidget>
<AdwWindowTitle title="App" />
</GtkHeaderBar.TitleWidget>
</AdwHeaderBar>
</AdwToolbarView.AddTopBar>
<MainContent />
</AdwToolbarView>
</AdwApplicationWindow>
```
### Styling with CSS-in-JS
```tsx
import { css } from "@gtkx/css";
<GtkButton
cssClasses={[
css`
background: #3584e4;
&:hover {
background: #1c71d8;
}
`,
]}
/>;
```
## Key Constraints
- GTK is single-threaded — all widget operations on main thread
- Virtual list items must be stable objects (immutable data patterns)
- Use `quit` from `@gtkx/react` to close the application
- Async GTK uses Promise methods, catch `NativeError` for failures
## References
See references/ for full widget catalog, tutorials, FFI bindings, styling, portals, testing, and deployment.
Related in Web Dev
generating-lwc-components
IncludedLightning Web Components with PICKLES methodology and 165-point scoring. Use this skill when the user creates or edits LWC components, builds wire service patterns, or writes Jest tests for LWC. TRIGGER when: user creates/edits LWC components, touches lwc/**/*.js, .html, .css, .js-meta.xml files, or asks about wire service, SLDS, or Jest LWC tests. DO NOT TRIGGER when: Apex classes (use generating-apex), Aura components, or Visualforce.
tanstack-query
IncludedManage server state in React with TanStack Query v5. Set up queries with useQuery, mutations with useMutation, configure QueryClient caching strategies, implement optimistic updates, and handle infinite scroll with useInfiniteQuery. Use when: setting up data fetching in React projects, migrating from v4 to v5, or fixing object syntax required errors, query callbacks removed issues, cacheTime renamed to gcTime, isPending vs isLoading confusion, keepPreviousData removed problems.
document-processor-api
IncludedProcess documents with Nutrient DWS. Use when the user wants to generate PDFs from HTML or URLs, convert Office/images/PDFs, assemble or split packets, OCR scans, extract text/tables/key-value pairs, redact PII, watermark, sign, fill forms, optimize PDFs, or produce compliance outputs like PDF/A or PDF/UA. Triggers include convert to PDF, merge these PDFs, OCR this scan, extract tables, redact PII, sign this PDF, make this PDF/A, or linearize for web delivery.
nutrient-document-processing
IncludedProcess documents with Nutrient DWS. Use when the user wants to generate PDFs from HTML or URLs, convert Office/images/PDFs, assemble or split packets, OCR scans, extract text/tables/key-value pairs, redact PII, watermark, sign, fill forms, optimize PDFs, or produce compliance outputs like PDF/A or PDF/UA. Triggers include convert to PDF, merge these PDFs, OCR this scan, extract tables, redact PII, sign this PDF, make this PDF/A, or linearize for web delivery.
tanstack-query
IncludedManage server state in React with TanStack Query v5. Covers useMutationState, simplified optimistic updates, throwOnError, network mode (offline/PWA), and infiniteQueryOptions. Use when setting up data fetching, fixing v4→v5 migration errors (object syntax, gcTime, isPending, keepPreviousData), or debugging SSR/hydration issues with streaming server components.
accelint-nextjs-best-practices
IncludedNext.js performance optimization and best practices. Use when writing Next.js code (App Router or Pages Router); implementing Server Components, Server Actions, or API routes; optimizing RSC serialization, data fetching, or server-side rendering; reviewing Next.js code for performance issues; fixing authentication in Server Actions; or implementing Suspense boundaries, parallel data fetching, or request deduplication.