Creating ryOS Applications

Quick Start Checklist

- [ ] 1. Create app directory: src/apps/[app-name]/
- [ ] 2. Create main component: components/[AppName]AppComponent.tsx
- [ ] 3. Create menu bar: components/[AppName]MenuBar.tsx
- [ ] 4. Create logic hook: hooks/use[AppName]Logic.ts
- [ ] 5. Create metadata: metadata.ts (appMetadata + exactly 6 help items)
- [ ] 6. Create app definition: index.tsx (re-export metadata, declare initialData type)
- [ ] 7. Add icon: choose from existing icons or the resource catalogs, then place active assets under `public/icons/<theme>/[app-name].png`
- [ ] 8. Register the app id: add to appIds + appNames in src/config/appRegistryData.ts
- [ ] 9. Register the app: lazy component + registry entry in src/config/appRegistry.tsx
- [ ] 10. Register help key order in src/hooks/useTranslatedHelpItems.ts
- [ ] 11. Add translation keys to src/lib/locales/en/translation.json
- [ ] 12. Localize (last): add en strings, sync locales; use the localize skill to finish

Directory Structure

src/apps/[app-name]/
├── components/
│   ├── [AppName]AppComponent.tsx  # Main component (required)
│   └── [AppName]MenuBar.tsx       # Menu bar (required)
├── hooks/
│   └── use[AppName]Logic.ts       # Logic hook (recommended)
├── metadata.ts                    # appMetadata + helpItems (required)
└── index.tsx                      # App definition: re-export metadata, initialData types (required)

Why metadata lives in its own file

appRegistry.tsx imports appMetadata/helpItems eagerly so the dock, About/Help dialogs, and search can show app info without loading the (lazy) component bundle. Keep these in a tiny metadata.ts that imports nothing heavy. Most current apps follow this split (@/apps/<id>/metadata). index.tsx then re-exports from metadata.ts and is the home for initialData types and any app-specific exported types.

1. Metadata (metadata.ts)

Keep app metadata and help items in metadata.ts so the registry can load them eagerly without pulling in the component.

export const appMetadata = {
  name: "[App Name]",
  version: "1.0.0",
  creator: { name: "Ryo Lu", url: "https://ryo.lu" },
  github: "https://github.com/ryokun6/ryos",
  icon: "/icons/default/[app-name].png",
};

// Always include exactly 6 help items (icon, title, description each).
export const helpItems = [
  { icon: "🚀", title: "Getting Started", description: "How to use this app" },
  { icon: "📂", title: "Open & Save", description: "Open and save files from the File menu" },
  { icon: "✏️", title: "Editing", description: "Use the Edit menu for cut, copy, paste" },
  { icon: "👁️", title: "View Options", description: "Adjust view and layout from the View menu" },
  { icon: "⌨️", title: "Shortcuts", description: "Use keyboard shortcuts for faster workflows" },
  { icon: "❓", title: "Help & About", description: "Open Help from the Help menu for more info" },
];

App icon sourcing

Before creating a new app icon from scratch, check the active icon themes and the historical icon resource catalogs:

1. Look for an existing logical icon in public/icons/default, public/icons/macosx, public/icons/win98, and public/icons/xp.
2. Search the resource catalogs for historically appropriate source art:

- Mac OS X: public/resources/macos-icon-catalogs/{panther,tiger}/catalog.md - Windows: public/resources/windows-icon-catalogs/{win98,xp}/catalog.md

1. If a catalog asset is the right source, copy or adapt it into the active icon tree (public/icons/<theme>/...) instead of referencing public/resources/... directly from app metadata.
2. Add at least public/icons/default/[app-name].png; add theme-specific variants when the catalog has a better era-matched asset.
3. Run bun run generate:icons after adding or moving active files under public/icons.

Keep public/resources/*-icon-catalogs as source libraries. Do not replace unrelated active icons just because a catalog contains a historical equivalent.

App Definition (index.tsx)

Re-export the metadata and declare any initialData type. This is what other files import as @/apps/[app-name].

export { appMetadata, helpItems } from "./metadata";

// Optional: typed startup payload for launchApp("[app-name]", { ... })
export interface [AppName]InitialData {
  // e.g. filePath?: string;
}

2. Main Component ([AppName]AppComponent.tsx)

import { WindowFrame } from "@/components/layout/WindowFrame";
import { [AppName]MenuBar } from "./[AppName]MenuBar";
import { AppProps } from "@/apps/base/types";
import { use[AppName]Logic } from "../hooks/use[AppName]Logic";
import { HelpDialog } from "@/components/dialogs/HelpDialog";
import { AboutDialog } from "@/components/dialogs/AboutDialog";
import { appMetadata } from "..";

export function [AppName]AppComponent({
  isWindowOpen,
  onClose,
  isForeground,
  skipInitialSound,
  instanceId,
}: AppProps) {
  const {
    t,
    translatedHelpItems,
    isHelpDialogOpen,
    setIsHelpDialogOpen,
    isAboutDialogOpen,
    setIsAboutDialogOpen,
    isWindowsTheme,
  } = use[AppName]Logic({ isWindowOpen, isForeground, instanceId });

  const menuBar = (
    <[AppName]MenuBar
      onClose={onClose}
      onShowHelp={() => setIsHelpDialogOpen(true)}
      onShowAbout={() => setIsAboutDialogOpen(true)}
    />
  );

  if (!isWindowOpen) return null;

  return (
    <>
      {!isWindowsTheme && isForeground && menuBar}
      <WindowFrame
        title={t("apps.[app-name].title")}
        onClose={onClose}
        isForeground={isForeground}
        appId="[app-name]"
        skipInitialSound={skipInitialSound}
        instanceId={instanceId}
        menuBar={isWindowsTheme ? menuBar : undefined}
      >
        <div className="flex flex-col h-full bg-os-window-bg font-os-ui">
          {/* App content */}
        </div>
      </WindowFrame>
      <HelpDialog
        isOpen={isHelpDialogOpen}
        onOpenChange={setIsHelpDialogOpen}
        appId="[app-name]"
        helpItems={translatedHelpItems}
      />
      <AboutDialog
        isOpen={isAboutDialogOpen}
        onOpenChange={setIsAboutDialogOpen}
        metadata={appMetadata}
        appId="[app-name]"
      />
    </>
  );
}

3. Logic Hook (use[AppName]Logic.ts)

import { useState } from "react";
import { useTranslation } from "react-i18next";
import { useTranslatedHelpItems } from "@/hooks/useTranslatedHelpItems";
import { useThemeStore } from "@/stores/useThemeStore";
import { helpItems } from "..";

export function use[AppName]Logic({ instanceId }: { instanceId: string }) {
  const { t } = useTranslation();
  const translatedHelpItems = useTranslatedHelpItems("[app-name]", helpItems);
  const currentTheme = useThemeStore((state) => state.current);
  const isWindowsTheme = currentTheme === "xp" || currentTheme === "win98";

  const [isHelpDialogOpen, setIsHelpDialogOpen] = useState(false);
  const [isAboutDialogOpen, setIsAboutDialogOpen] = useState(false);

  return {
    t,
    translatedHelpItems,
    isWindowsTheme,
    isHelpDialogOpen,
    setIsHelpDialogOpen,
    isAboutDialogOpen,
    setIsAboutDialogOpen,
  };
}

4. Menu Bar ([AppName]MenuBar.tsx)

Match existing app menubars: structure, classes, and spacing.

• Wrapper: <MenuBar inWindowFrame={isWindowsTheme}> — no extra gap between menus (layout uses space-x-0).
• Trigger: MenubarTrigger className="text-md px-2 py-1 border-none focus-visible:ring-0".
• Content: MenubarContent align="start" sideOffset={1} className="px-0".
• Items: MenubarItem className="text-md h-6 px-3".
• Separators: MenubarSeparator className="h-[2px] bg-black my-1".

import { MenuBar } from "@/components/layout/MenuBar";
import {
  MenubarMenu,
  MenubarTrigger,
  MenubarContent,
  MenubarItem,
  MenubarSeparator,
} from "@/components/ui/menubar";
import { useThemeStore } from "@/stores/useThemeStore";
import { useTranslation } from "react-i18next";

interface [AppName]MenuBarProps {
  onClose: () => void;
  onShowHelp: () => void;
  onShowAbout: () => void;
}

export function [AppName]MenuBar({ onClose, onShowHelp, onShowAbout }: [AppName]MenuBarProps) {
  const { t } = useTranslation();
  const currentTheme = useThemeStore((state) => state.current);
  const isWindowsTheme = currentTheme === "xp" || currentTheme === "win98";
  const isMacOSTheme = currentTheme === "macosx";

  return (
    <MenuBar inWindowFrame={isWindowsTheme}>
      <MenubarMenu>
        <MenubarTrigger className="text-md px-2 py-1 border-none focus-visible:ring-0">
          {t("common.menu.file")}
        </MenubarTrigger>
        <MenubarContent align="start" sideOffset={1} className="px-0">
          <MenubarSeparator className="h-[2px] bg-black my-1" />
          <MenubarItem onClick={onClose} className="text-md h-6 px-3">
            {t("common.menu.close")}
          </MenubarItem>
        </MenubarContent>
      </MenubarMenu>
      <MenubarMenu>
        <MenubarTrigger className="text-md px-2 py-1 border-none focus-visible:ring-0">
          {t("common.menu.help")}
        </MenubarTrigger>
        <MenubarContent align="start" sideOffset={1} className="px-0">
          <MenubarItem onClick={onShowHelp} className="text-md h-6 px-3">
            {t("apps.[app-name].menu.help")}
          </MenubarItem>
          {!isMacOSTheme && (
            <>
              <MenubarSeparator className="h-[2px] bg-black my-1" />
              <MenubarItem onClick={onShowAbout} className="text-md h-6 px-3">
                {t("apps.[app-name].menu.about")}
              </MenubarItem>
            </>
          )}
        </MenubarContent>
      </MenubarMenu>
    </MenuBar>
  );
}

5. Register the App ID (appRegistryData.ts)

The AppId union type, dock/search ordering, and store lookups all derive from src/config/appRegistryData.ts. Add the id here first — otherwise appRegistry.tsx (and everything typed against AppId) will not compile.

// src/config/appRegistryData.ts
export const appIds = [
  // ...existing ids...
  "[app-name]",
] as const;

export const appNames: Record<AppId, string> = {
  // ...existing names...
  "[app-name]": "[App Name]",
};

If you ever rename an app's id, add the old id to LEGACYAPPID_ALIASES so persisted/bookmarked references still resolve.

6. Register in appRegistry.tsx

createLazyComponent lives in src/config/lazyAppComponent.tsx (already imported at the top of appRegistry.tsx) and registers the chunk for intent-based prefetch. Import metadata from the lightweight metadata.ts, not the component.

// Metadata import (eager, lightweight) — note the /metadata path
import { appMetadata as [appName]Metadata, helpItems as [appName]HelpItems } from "@/apps/[app-name]/metadata";

// Lazy component (loaded on open). Use your initialData type instead of unknown if you declared one.
const Lazy[AppName]App = createLazyComponent<unknown>(
  () => import("@/apps/[app-name]/components/[AppName]AppComponent")
    .then(m => ({ default: m.[AppName]AppComponent })),
  "[app-name]" // cache key = app id, keeps refs stable across HMR + enables prefetch
);

// Add to the appRegistry object
["[app-name]"]: {
  id: "[app-name]",
  name: "[App Name]",
  icon: { type: "image", src: [appName]Metadata.icon },
  description: "App description",
  component: Lazy[AppName]App,
  helpItems: [appName]HelpItems,
  metadata: [appName]Metadata,
  windowConfig: {
    defaultSize: { width: 650, height: 475 },
    minSize: { width: 400, height: 300 },
  } as WindowConstraints,
},

7. Register help keys

useTranslatedHelpItems("[app-name]", helpItems) needs a matching key list in APPHELPI18N_KEYS in src/hooks/useTranslatedHelpItems.ts. Keep the list in the same order as metadata.ts helpItems; the hook preserves the icons and swaps in apps.[app-name].help.[key].title and .description.

For longer help lists, create src/apps/[app-name]/helpKeys.ts and spread that exported list into APPHELPI18N_KEYS. Calculator, Maps, and Internet Explorer are good examples.

Run bun test tests/unit/i18n/test-help-i18n-alignment.test.ts after adding the app. It catches missing help keys and row-count drift across every registered app.

AppProps Interface

Menu Bar Placement

• macOS/System7: Render outside WindowFrame when isForeground
• XP/Win98: Pass via menuBar prop to WindowFrame

const isWindowsTheme = currentTheme === "xp" || currentTheme === "win98";
return (
  <>
    {!isWindowsTheme && isForeground && menuBar}
    <WindowFrame menuBar={isWindowsTheme ? menuBar : undefined}>

WindowFrame Options

Common Patterns

Initial Data

interface ViewerInitialData { filePath: string; }
export function ViewerAppComponent({ initialData }: AppProps<ViewerInitialData>) {
  const filePath = initialData?.filePath ?? "";
}

Launch Other Apps

import { useLaunchApp } from "@/hooks/useLaunchApp";
const launchApp = useLaunchApp();
launchApp("photos", { path: "/image.png" });

Global Store (Zustand)

// src/stores/use[AppName]Store.ts
import { create } from "zustand";
import { persist } from "zustand/middleware";

export const use[AppName]Store = create<State>()(
  persist((set) => ({ /* state and actions */ }), { name: "[app-name]-storage" })
);

8. Localize (Do Last)

After the app is built and wired up, finish by localizing:

1. Add translation keys for all user-facing strings (menu labels, dialogs, status, help).
2. Add English entries under apps.[app-name].* in src/lib/locales/en/translation.json.
3. Sync other locales with bun run i18n:sync:mark-todo.
4. Validate with bun run i18n:sync:dry-run, bun run i18n:audit, and the help alignment test.

Use the localize skill for the full workflow: extract strings → t() calls → en keys → sync. Do this step last so all UI copy is stable before extracting and syncing.