The same problems. A different shape.

import { type Result, token, unit } from '@staticflux/core';
import { DataClientToken } from '@staticflux/data';

export interface DocsService {
  list(signal: AbortSignal): Promise<Result<DocsPage>>;
}
export const DocsServiceToken = token('docs/service').type<DocsService>();

export const docsServiceUnit = unit({
  id: 'docs/service-unit',
  provides: DocsServiceToken,
  scope: 'session',                     // disposed on logout, with what it holds
  deps: { required: { client: DataClientToken } },
  create: ({ client }): DocsService => ({
    list: (signal) => client.call(DocsListEndpoint, { cursor: undefined }, { signal }),
  }),
});

// consumers declare the token; nothing is built until something asks for it
const docs = await injector.get(DocsServiceToken);

import { component, defineComponent, SfElement } from '@staticflux/ui';
import { html } from 'lit';

const toolbarSpec = component({
  tag: 'doc-toolbar',
  deps: {
    render: { doc: DocumentStoreToken },                               // placeholder until ready
    lazy: { presence: { token: PresenceToken, init: 'on-visible' } }, // reactive, arrives later
    functional: { exportPdf: { token: ExportPdfToken, init: 'on-intent' } }, // loads on hover/focus
  },
  size: { block: '48px' },                                             // reserved: no layout shift
});

export class DocToolbar extends SfElement<typeof toolbarSpec> {
  static override readonly spec = toolbarSpec;
  override render() {
    const { doc, presence, exportPdf } = this.deps;
    return html`
      <h2>${doc.title}</h2>
      <span>${presence.value?.count ?? 0} editing</span>
      <button data-sf-intent=${this.intent('exportPdf')} @click=${async () => {
        const exporter = await exportPdf.get();
        if (exporter.ok) await exporter.value.run(doc.docId);
      }}>PDF</button>`;
  }
}
defineComponent(DocToolbar);

// contracts.ts — typed declarations
export const OnboardingVariantFlag = defineFlag({
  key: 'onboarding/variant', type: flagType.enum(['A', 'B']), default: 'A',
  owner: 'onboarding', preAuthSafe: true, description: 'Onboarding copy experiment.',
});
export const OnboardingCopyToken = token('onboarding/copy').type<OnboardingCopy>();

// compose.ts — one unit per variant; the binder turns the flag into bindings
const copyA = unit({ id: 'onboarding/copy-a-unit', provides: OnboardingCopyToken, scope: 'app',
  create: () => ({ headline: 'Let’s set up your studio' }) });
const copyB = unit({ id: 'onboarding/copy-b-unit', provides: OnboardingCopyToken, scope: 'app',
  create: () => ({ headline: 'Three steps to your first document' }) });

const binder = createFlagBinder();
const units = [
  flagResolverUnit({ initTimeoutMs: 1500 }), flagBinderUnit(binder), copyA,
  ...binder.variants({ flag: OnboardingVariantFlag, of: OnboardingCopyToken, variants: { B: copyB } }),
];

// feature code injects the token — it never sees the flag
deps: { render: { copy: OnboardingCopyToken } }   // → html`<h1>${this.deps.copy.headline}</h1>`

import { effect, type Scope, sleep, task } from '@staticflux/core';

export function startMinimap(owner: Scope, view: MinimapView): void {
  const scope = owner.child('minimap');               // disposed with its owner

  scope.listen(window, 'resize', () => view.fit());  // removed on dispose
  effect(() => view.redraw(store.blocks), scope);    // reactive; stops on dispose

  void (async () => {                                 // abortable polling loop
    while (!scope.disposed) {
      await view.poll(scope.signal);
      if (!(await sleep(5_000, scope.signal)).ok) return;
    }
  })();

  const thumbs = task((signal) => fetch(`/api/thumbs/${view.id}`, { signal }).then((r) => r.json()));
  void thumbs(scope.signal).then((r) => { if (r.ok) view.draw(r.value); }); // aborted, never late
}
// the feature's UI scope is the owner: unmount → dispose → all of the above stops

// the dialog is part of the doc route's URL: /studio/doc/42/d/share
export const ShareDialogRoute = defineDialog({
  id: 'studio/share', key: 'share', owner: DocRoute, requires: { auth: 'required' },
});

// declared once; the surface manager renders, stacks, traps and restores focus
export const ShareDialog = defineSurface<{ readonly docId: string }>({
  id: 'studio/share-dialog',
  kind: 'dialog',
  scope: 'route',                  // can never outlive its route (invariant I-7)
  label: 'Share document',
  routable: { key: 'share', params: (raw) => ok({ docId: raw['id'] ?? '' }) },
  render: ({ props, dismiss, titleId }) => html`
    <h2 id=${titleId}>Share document ${props.docId}</h2>
    <button @click=${() => dismiss('completed')}>Done</button>`,
});
export const shareDialogUnit = contribution({
  id: 'studio/share-dialog-surface-unit', provides: RoutableSurfacesToken, scope: 'app',
  create: () => ShareDialog,
});

// open it like a route: availability → authorize → load → enter
html`<button @click=${() => void router.openDialogRoute(ShareDialogRoute)}>Share</button>`

import { attemptAsync, defineError, err, retry, type Task, timeout } from '@staticflux/core';

export const DocNotFound = defineError('APP-DOC-001', 'not-found',
  'The document does not exist.', 'Check the id; offer to create a new document.');
export const DocUnavailable = defineError('APP-DOC-002', 'unavailable',
  'The document service is unavailable.', 'Keep the cached copy read-only and retry later.');

const fetchDoc = (id: string): Task<Doc> => async (signal) => {
  const res = await attemptAsync(() => fetch(`/api/docs/${id}`, { signal }));
  if (!res.ok) return res;
  if (res.value.status === 404) return err(DocNotFound({ details: { id } }));  // never retried
  if (!res.value.ok) return err(DocUnavailable({ details: { status: res.value.status } }));
  return attemptAsync(() => res.value.json() as Promise<Doc>);
};

// 5 s per attempt, 3 attempts, full-jitter backoff; aborting the signal stops everything
const loadDoc = (id: string) => retry(timeout(fetchDoc(id), 5_000), { attempts: 3, baseDelayMs: 200 });

const result = await loadDoc('42')(scope.signal);
if (!result.ok) showError(result.error.code, result.error.fix);

import { metric, unit } from '@staticflux/core';
import { defineMarkBudget, markBudgetUnit, perfUnits } from '@staticflux/perf';
import { defineFeature } from '@staticflux/runtime';

// typed metric; producers declare informs, consumers reads (checked by the graph tool)
export const ExportDuration = metric.histogram('studio/export-duration', { unit: 'ms' });

export const exportUnit = unit({
  id: 'studio/export-unit', provides: ExportToken, scope: 'feature', informs: [ExportDuration],
  create: (_deps, ctx) => ({
    async run(id: string) {
      const start = ctx.telemetry.now();
      const result = await exportPdf(id, ctx.signal);
      ctx.telemetry.record(ExportDuration, ctx.telemetry.now() - start, { ok: result.ok });
      return result;
    },
  }),
});

// feature marks are framework-measured; declare who reports which
defineFeature({ id: Features.studioDesktop.id, weight: 'heavy', load,
  readiness: { firstRender: 'framework', interactive: 'feature', complete: 'feature' } });

// opt in once: a journey trace per navigation, budgets per mark × start × device tier
const units = [...perfUnits, markBudgetUnit(defineMarkBudget({
  feature: 'studio/desktop', mark: 'interactive', maxMs: 700, starts: ['warm'], reason: 'R12.7' }))];

import { createIndexedDbStore, createLocalStorageStore, createMemoryStore, createStore } from '@staticflux/storage';

// first available backend wins; failures at runtime fail over (reported)
const prefs = createStore<Prefs>({
  backend: [createIndexedDbStore({ namespace: 'prefs' }), createLocalStorageStore({ prefix: 'app:' }),
    () => createMemoryStore()],
});
if (!prefs.ok) return prefs;                 // only when no backend is available at all

const theme = await prefs.value.get('theme', { signal });   // Promise<Result<Prefs | undefined>>
if (!theme.ok && theme.error.code === 'SF-STORE-001') warnQuotaFull();  // typed errors
await prefs.value.set('theme', { mode: 'dark' });

prefs.value.watch((change) => {             // cross-tab changes, same interface
  if (change.type === 'set' && change.origin === 'external') reload(change.key);
});

import { authorizedTransportUnit, bffCookieProviderUnit, createSessionUnit,
  fetchAuthTransportUnit } from '@staticflux/auth';

const auth = [
  // recommended: tokens stay in the BFF; the browser sees a session endpoint + CSRF header
  bffCookieProviderUnit({ endpoints: BFF_ENDPOINTS, csrf: { header: 'x-csrf' } }),
  createSessionUnit({ channelName: 'app/session' }), // one session model, synced across tabs
  fetchAuthTransportUnit,
  authorizedTransportUnit,   // grant headers in; 401 → ONE single-flight refresh → one retry
  epochRefreshListenerUnit,  // session change → supervisor.refresh(): the epoch bumps
];

// data that must follow the user re-initializes on the epoch; stale responses are dropped
export const docsUnit = unit({
  id: 'docs/list-unit', provides: DocsToken, scope: 'session', refreshOn: ['epoch'],
  deps: { required: { resources: ResourcesToken } },
  create: ({ resources }) => createDocsList(resources),
});

// typed route; the feature binds to a capability and the router picks the per-mode variant
export const DocRoute = defineRoute({
  id: 'studio/doc', parent: StudioRoute, path: 'doc/:id',
  search: { tab: searchParam.enum(['content', 'comments', 'history'], { default: 'content', kind: 'view' }) },
  feature: bindCapability('studio/editor', [
    { feature: Features.studioDesktop, modes: ['expanded', 'medium'] },
    { feature: Features.studioMobile, modes: ['compact'] },
  ]),
});

// leaving the editor waits for the save: async, uninterruptible, bound to the UI scope
router.guardExit(DocRoute, guard(async (_navigation, signal) => {
  const flushed = await doc.flush(signal);
  return flushed.ok ? proceed() : err(flushed.error);
}, { uninterruptible: true, name: 'studio/save-before-leave' }), uiScope);

// typed params; newest navigation cancels older ones; Back runs the same pipeline
const result = await router.navigate({ to: DocRoute, params: { id: '42' } });

import { attachDeltaStream, createDeltaStream, defineDeltaStream, selectMedium } from '@staticflux/worker/pipeline';

export const Scene = defineDeltaStream({ id: 'app/scene', capacityBytes: 1 << 20 });

// editor: versioned records; a snapshot whenever a reader asks for one
const deltas = createDeltaStream(Scene, { medium: selectMedium({ topology: boot.topology }) });
if (!deltas.ok) return deltas;
deltas.value.onResnapshot(() => deltas.value.snapshot({ version, payload: encodeScene() }));
deltas.value.append({ version: ++version, payload: encodeChange(change) });

// renderer: per vsync, apply what has arrived — up to the version the view frame shows
const reader = await attachDeltaStream(Scene, endpoint);
if (!reader.ok) return reader;
reader.value.apply(applyToScene, { upTo: viewFrame.docVersion });
// a gap or epoch change → resyncing → snapshot → live; never a guess past a hole

// the vocabulary is closed: only registered contributions can mount
defineSpecContribution({ section: 'tool', id: 'app/heal', label: 'Heal', when: { lens: ['app/pixel'] } });
defineSpecContribution({ section: 'panel', id: 'app/layers', label: 'Layers', gate: gateResource('ui-slot', 'app/layers') });

// a screen is data: validated, gated, then applied as a minimal diff
const applied = await specs.apply({
  id: 'app/retouch', context: { lens: 'app/pixel' },
  slots: [{ section: 'tool', id: 'app/pen' }, { section: 'tool', id: 'app/heal' },
          { section: 'panel', id: 'app/layers', placement: 'dock' }],
}, { signal });
// the pen stays mounted; heal enters, layers moves — 120–200 ms each, 0 under reduced motion

import { availableLinkTransports, availablePipeMedia, runDeltaStreamContract, runPeerChannelContract,
  brokeredPeerSetup, runRasterBackendContract } from '@staticflux/testkit';

for (const medium of availablePipeMedia()) runDeltaStreamContract(medium, { describe, it });   // local · shared · message
for (const transport of availableLinkTransports()) runPeerChannelContract(brokeredPeerSetup(transport), { describe, it });

// every RasterBackend: the CPU reference in Node, the app's WebGPU backend in Chromium
runRasterBackendContract('memory', () => ({ backend: createMemoryRasterBackend({ tileSize: 64 }), scene, tolerance: 0 }), { describe, it });