Nitro-V3/CLAUDE.md

Claude Code — project memory for Nitro-V3

This file is read automatically by Claude Code at session start. It captures the conventions and current state of this branch so a new session can hit the ground running.

TL;DR

This branch — feat/react19-modernization — is a long-running modernization of the Nitro V3 client: bump to React 19.2 idioms, add the supporting infrastructure (TanStack Query, Zustand, Vitest, React Compiler, error boundaries), split a few god-hooks, and audit logic bugs along the way. PR is #2 on simoleo89/Nitro-V3.

Detailed status, decisions, and next steps live in docs/ARCHITECTURE.md — read that before starting anything non-trivial.

Commands

Goal	Command
Dev server	yarn start
Production build	yarn build
Lint	yarn eslint
Type-check (TS 7 native, fast)	yarn typecheck
Test (Vitest, once)	yarn test
Test (watch)	yarn test:watch

The renderer SDK (@nitrots/nitro-renderer) is consumed via a filesystem link to a sibling working tree — ../Nitro_Render_V3 (preferred) or ../renderer (legacy). Without it, yarn typecheck reports TS2307 across the codebase — that's expected on a sandbox without the renderer, not a regression.

Stack snapshot

• React 19.2.5, react-dom 19.2.5, @types/react 19.2.x.
• TypeScript: TS 6 for build, TS 7 native preview (@typescript/native-preview, invoked via tsgo) for the typecheck script.
• Vite 8 + @vitejs/plugin-react 6 + babel-plugin-react-compiler 1.0.
• ESLint 10 + typescript-eslint 8 + eslint-plugin-react-hooks@7 + eslint-plugin-react-compiler.
• TanStack Query 5 (@tanstack/react-query + devtools).
• Zustand 5.
• Vitest 3 + jsdom + @testing-library/react + @testing-library/jest-dom.
• react-error-boundary 6.

Layout convention (DO NOT CHANGE)

Established by the team and recorded in docs/ARCHITECTURE.md proposal #3 (rejected the src/features/ alternative). Stay on this layout — every PR that violates it will need to be reworked.

src/components/<area>/<feature>/         → views (.tsx only)
  e.g. src/components/room/widgets/doorbell/DoorbellWidgetView.tsx

src/hooks/<area>/<feature?>/             → hooks, FLAT files, no per-feature subfolder
  e.g. src/hooks/rooms/widgets/useDoorbellState.ts
       src/hooks/rooms/widgets/useDoorbellActions.ts
       src/hooks/rooms/widgets/useDoorbellWidget.ts (deprecated shim)

src/api/                                 → cross-cutting helpers (LocalizeText, composers, formatters)
src/common/                              → reusable UI primitives + error boundary
src/state/                               → Zustand stores (cross-feature only)
tests/                                   → Vitest suites (mirror filename of subject)

When splitting a god-hook the convention is 3 files, all flat in the hooks barrel directory:

• use<Feature>State.ts — state + event subscriptions + derived values
• use<Feature>Actions.ts — pure imperative actions (no state writes)
• use<Feature>Widget.ts — deprecated wrapper that composes the two and preserves the old return shape so existing consumers don't break

See useDoorbellState/useDoorbellActions/useDoorbellWidget as the canonical pattern.

Patterns to use

useNitroEventState / useMessageEventState

For "derived state from a single event" replace the two-step useState + useNitroEvent(e => setState(...)) with a single call:

const foo = useNitroEventState(SomeEvent, e => e.payload, initial);
const data = useMessageEventState(SomeParser, e => e.getParser()?.field ?? null, null);

The selector is held in a useLayoutEffect-refreshed ref so the listener stays registered across renders. Both hooks are exported from src/hooks/events.

useNitroQuery

For composer/parser request-response pairs:

const { data } = useNitroQuery<SomeParser, SomeData>({
    key: ['nitro', 'domain', 'request', ...args],
    request: () => new SomeComposer(args),
    parser: SomeParser,
    select: e => e.getParser()?.data,
    accept: e => e.getParser()?.correlationKey === args, // optional, for shared event bus
    staleTime: 60_000,
});

Already wired up; QueryClientProvider is mounted in src/index.tsx. Adopted on OfferView, CatalogLayoutRoomAdsView, ModToolsChatlogView, CfhChatlogView.

Zustand stores

For cross-feature UI state (avoid module-level let):

import { createNitroStore } from '@/state/createNitroStore';

export const useFooStore = createNitroStore<FooState>()((set) => ({
    ...
}));

Components subscribe to slices, not the whole store:

const value = useFooStore(s => s.value);

First adoption: src/components/navigator/views/navigatorRoomCreatorStore.ts.

WidgetErrorBoundary

Wrap any in-room widget tree so a crash degrades gracefully (logs to NitroLogger, falls back to null). Already applied at RoomWidgetsView as an umbrella; per-widget wrapping is a follow-up.

<WidgetErrorBoundary name="ChatWidget">
    <ChatWidgetView />
</WidgetErrorBoundary>

Form Actions

Login / Register / Forgot in src/components/login/LoginView.tsx use useActionState + useFormStatus. The legacy non-Action versions in src/components/login/components/{Register,Forgot}Dialog.tsx and shared.ts have been removed (dead code).

What's wired up and what isn't

Adopted	Pilot sites
useNitroEventState + companions (Reducer, ExternalSnapshot)	OfferView, useAvatarInfoWidget (figure/badges/group reducer), useInventoryFurni (pure reducers + fragments useRef)
useNitroQuery + useNitroEventInvalidator	OfferView, CatalogLayoutRoomAdsView, ModToolsChatlogView, CfhChatlogView, useGiftConfiguration, useUserGroups, useClubOffers(windowId), useSellablePetPalette(breed), useMarketplaceConfiguration, useClubGifts (with invalidator)
Zustand	NavigatorRoomCreatorView (useRoomCreatorStore)
God-hook split (state + actions + shim)	doorbell, poll, furni-chooser, user-chooser, friend-request, chat-input
God-hook split (useBetween singleton + state filter + actions filter + shim)	wired-tools, translation
WidgetErrorBoundary	RoomWidgetsView umbrella
Vitest	99/99 cases on pure helpers + the Zustand store

Not yet	Notes
Core useCatalog split	Session-stable secondary fetches all migrated to TanStack queries (see ARCHITECTURE.md). What's left: core rootNode/offersToNodes/currentPage slice + Builders Club status. Needs a dedicated useCatalogData/useCatalogUiState/useCatalogActions split.
Split useChatWidget / useAvatarInfoWidget	Both state-driven via events with no clean imperative actions to extract — skip-motivated. Already touched today for the InfoStand listener move.
Split usePetPackageWidget / useWordQuizWidget / useChatCommandSelector	Their "actions" mutate internal state or are tightly interdependent — skip-motivated.
Hoist Wired Creator Tools shared state to a Zustand slice	Would remove ~25 props passed to the 3 tab sub-components. (Wired-tools split done as singleton-filter; Zustand slice is the next step.)
Wider Vitest coverage (React components)	@testing-library/* is installed; needs a small renderer-SDK mock layer first.

Known open logic bugs

Read docs/ARCHITECTURE.md "Known logic bugs" section. The two still-open ones:

• MainView.tsx:47-48 — race between RoomSessionEvent.CREATED and ENDED (no session token guard).
• LayoutFurniImageView / LayoutAvatarImageView — async fetch race when props change twice in quick succession.

Fix shapes documented; both are reasonable PRs on their own.

House rules

• Commit author: simoleo89 <simoleo89@users.noreply.github.com>. When committing, pass these via per-command overrides (git -c user.name=simoleo89 -c user.email=...) — do NOT modify the global git config.
• No claude/... branch names — auto-generated names should be renamed before pushing. Prefer feat/<description>.
• Never merge a branch that violates the layout convention above. The feat/react19-hooks-adapter branch (deleted) put hooks under src/components/...; that's wrong and a recurring temptation.
• Skip-motivated god-hook splits are fine — when a hook's actions mutate internal state, document the reason in the commit message and move on rather than forcing a bad split.
• yarn test must stay green on every commit. Currently 99/99.
• Lint baseline: don't regress. Some pre-existing errors (FC<{}>, IMessageEvent | undefined redundant union in the local sandbox where the renderer SDK isn't installed) are out of scope here.

Where everything lives

• Architecture doc: docs/ARCHITECTURE.md
• Test runner config: vitest.config.mts (separate from vite.config.mjs)
• Test setup: tests/setup.ts
• React Query adapter: src/api/nitro-query/createNitroQuery.ts
• Zustand factory: src/state/createNitroStore.ts
• Error boundary: src/common/error-boundary/WidgetErrorBoundary.tsx
• Event hooks (useNitroEvent, useMessageEvent, useNitroEventState, useMessageEventState): src/hooks/events/
• Wired-tools split (types/constants/helpers + 3 tab views): src/components/wired-tools/