**TL;DR:** Below is a phase-by-phase implementation guide: what libraries we’ll use, what kinds of tests we’ll write, what contracts/functions we’ll define, and how we’ll validate each step. Still high-level—no filenames or code dropped—yet detailed enough to steer day-to-day work.

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# Q-Blog → 1.0.0 Implementation Plan (Technical, High-Level)

## Phase 0 — Orientation & Quality Bar

**Libraries / tools**

- Issue labels & PR templates (tracker-native).
- Metrics: Web Vitals (`web-vitals`), synthetic a11y checks (`axe-core` via CI).
  **Artifacts**
- **Quality charter**: SLOs (e.g., “save post success ≥ 99.9%”), accessibility bar (keyboard-only paths pass), perf budgets (LCP/INP).
- **Protected journeys** list: _read post, create post, edit post, manage blogs_.
  **Validation**
- Signed-off charter; journeys ratified in a short doc.

---

## Phase 1 — Project Docs & Working Agreements

**Libraries / tools**

- Diagrams as code (Mermaid in docs renderer).
- Conventional commits (tooling optional).
  **Artifacts**
- **Architecture map** (UI ↔ state ↔ API), **Testing pyramid**, **A11y standard**, **Contributing rules**, **Changelog categories**.
- **Decision Record template** (context → options → decision → impact).
  **Validation**
- New contributor dry run: “can run + test + understand contracts in <30 min.”

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## Phase 2 — Test Harness & Linting Baseline

**Libraries**

- Unit/Component: **Vitest**, **@testing-library/react**, **@testing-library/user-event**, **@testing-library/jest-dom**.
- A11y lint/checks: **eslint-plugin-jsx-a11y**, **axe-core** or **jest-axe**.
- Mocking: **MSW** (Mock Service Worker) for API.
- Types: TypeScript strict mode.
- Lint/format: **eslint** (flat config), **@typescript-eslint** plugin, **prettier**.
  **Key setup**
- Global test setup (RTL matchers, MSW server, clock/timers).
- Coverage thresholds (e.g., 80/70/70 lines/branches/functions to start).
- CI lanes: install/cache → typecheck → lint → unit/component → (later) e2e smoke.
  **Tests to seed**
- Smoke renders: home, post list, editor screen.
- Tiny interaction: typing in editor, enabling/disabling toolbar control, save button disabled until valid.
  **Validation**
- Green **typecheck + lint + tests** on clean checkout; coverage reports generated.

---

## Phase 3 — Correctness Sweep

**Libraries**

- RTK ecosystem: **@reduxjs/toolkit** (already present), **RTK Query** for data-fetching (adds caching, retries, invalidation).
- Schema/runtime validation: **Zod** (form/io validation) **and** `zod-to-json-schema` for docs **or** **AJV** if we align with JSON Schema like Q-Chess. (Pick one; see “Contracts” below.)
  **Contracts / functions**
- **Fetch layer** with cancellation & retries:

  - `fetchJson<T>(req: Request, opts): Promise<Result<T>>`
  - `withTimeout(controller, ms): AbortSignal`

- **Async state convention**: `{ status: 'idle'|'loading'|'success'|'error', data?, error? }`.
- **Error object**: `{ code: string; message: string; recoverable: boolean }`.
- **Validation**:

  - For Zod: `const PostDto = z.object({ id: z.string(), ... })` → `parse(response)`.
  - For AJV: compile JSON Schemas once; validate per response.
    **Work items**

- Remove legacy UI imports (v4 → v5), delete `ts-nocheck` sections by adding minimal types.
- Replace `any` in reducers/selectors and editor props with discriminated unions & precise payloads.
- Normalize empty/loading/error states for all remote views.
  **Tests**
- Contract tests: MSW returns both **valid** and **invalid** payloads → validation errors surface as user-friendly messages.
- Reducer tests: transitions for each thunk/query state.
  **Validation**
- No suppressed type regions; “known issues” list empty; core routes never hard-crash on bad data.

---

## Phase 4 — Accessibility Baseline

**Libraries**

- A11y testing: **jest-axe** or **axe-core** integration; **testing-library** queries by role/name.
- Focus management: rely on MUI’s **Dialog/Popover** focus traps; add **focus-trap** only where needed.
  **Contracts / behaviors**
- **Landmarks**: header/nav/main/footer; **Skip link** available and visible on focus.
- **Focus policy**: focus moves to first interactive element on open; returns to invoker on close.
- **Names/roles/states**: toggles expose `aria-pressed`; inputs have programmatic labels; errors are linked with `aria-describedby`.
- **Live regions**: polite updates for “saving…/uploaded/failed”.
- **Motion/contrast**: respect `prefers-reduced-motion`; enforce contrast tokens.
  **Tests**
- Keyboard paths for protected journeys (Tab/Shift+Tab order, Escape close).
- axe checks for key pages (no critical violations).
- Live region announces long-running operations (assertions via `toHaveAccessibleDescription` or role queries).
  **Validation**
- Keyboard-only success across protected journeys; automated checks pass with zero criticals.

---

## Phase 5 — UX & IA Touch-up

**Libraries**

- Router (current choice): ensure route guards & prefetch hooks supported.
- Toasts/banners: lightweight (e.g., notistack or MUI Snackbar pattern).
  **Contracts / functions**
- **Design tokens**: spacing, radius, typography, color roles (text, surface, brand) centralized.
- **Common UI patterns**:

  - Empty state contract: `{ icon?, title, body, primaryAction?, secondaryAction? }`
  - Error surface: banner + inline guidance; all errors have recovery action.

- **Editor ergonomics**:

  - Toolbar state machine: `computeToolbarState({ selection, schema }) → { boldEnabled, … }`
  - Draft lifecycle: `autosaveDraft(postId, content) → { savedAt }` with debounce and “last saved” indicator.
    **Tests**

- Token snapshots for theme roles; editor toolbar enable/disable based on selection.
- Error/empty states render consistently across pages (table-driven tests).
  **Validation**
- Navigation clarity (first-click discoverability); zero dead ends; consistent affordances.

---

## Phase 6 — Multiple Blogs per Name

**Libraries**

- State & data: continue **RTK Query** (cache per blog key).
- Validation: same as Phase 3 (Zod/AJV).
  **Domain model**
- **Name** (account) 1..N **Blog**; **Post** 1..1 **Blog** (immutable relationship post-creation).
- **Identifiers**:

  - Blog handle: lowercase, slug rules; unique per **Name**; stored canonical form.
  - URL composition: `/{name}/{blogHandle}/…` (conceptual, router-agnostic).
    **Functions / contracts**

- `listBlogs(name): Promise<Blog[]>`
- `createBlog(input: { handle; title; visibility }): Promise<Blog>`
- `switchBlog(handle): void` (updates app-scoped “current blog”)
- `listPosts(blogId, filters)`, `createPost(blogId, input)`
- **Migration**: `backfillDefaultBlogs(): MigrationResult` (idempotent: skip if blog exists)
  **Tests**
- Migration test with legacy dataset → posts appear under default blog.
- Router/selector scoping: when switching blogs, lists & counts update without leaking data.
- Handle validation: rejects collisions & invalid slugs; normalizes input.
  **Validation**
- Users can create/switch blogs; all lists/summaries are scoped; legacy users retained seamlessly.

---

## Phase 7 — Shared Blogs (Collaboration)

**Libraries**

- Role/permission helpers: in-house constants; optional **casl** if we want DSL-like permissions (not required).
  **Role model**
- **Owner**, **Editor**, **Author**, **Viewer** (implicit).
- Operation matrix:

  - Owner: all
  - Editor: edit any post, manage drafts
  - Author: CRUD own posts
    **Functions / contracts**

- Membership:

  - `inviteMember(blogId, name, role): InviteToken`
  - `acceptInvite(token): Membership`
  - `removeMember(blogId, name): void`
  - `listMembers(blogId): Membership[]`

- Authorization guard:

  - `can(op: 'create'|'edit'|'publish'|'manageMembers', ctx: { user, blog, post? }): boolean`

- Attribution:

  - Post metadata: `{ createdBy, updatedBy, updatedAt, revision }`

- Concurrency:

  - `savePost(postId, input, { ifMatchRevision }): { revision }` → 409 on stale; client shows resolve UI.
    **Tests**

- Permission matrix table tests (unit): each role × operation result.
- API guard tests via MSW: simulate forbidden responses, assert UI disables and surfaces denial.
- Concurrency tests: stale write attempt returns conflict → user offered resolve path.
  **Validation**
- Owner can manage access; editors/authors can work within role; no unauthorized writes pass.

---

## Milestone Updates

- v0.1.x — Multiblog foundations and quality baselines delivered.
- v0.2.0 — Wiki Mode canonical selection shipped (owner/whitelist/blacklist; canonical dedupe across Names in feed, favorites, subscriptions, and post view). Settings cache added for efficient owner/settings resolution.

## Phase 8 — Performance & Resilience

**Libraries**

- **react-virtuoso** or equivalent (already used) for long lists.
- Data layer retries/backoff: **RTK Query**’s retry plugin or custom wrapper.
- RUM metrics: **web-vitals** + lightweight sender.
  **Functions / policies**
- **Optimistic updates** where safe (draft save, title edits) with rollback on failure.
- **Retry policy**: GETs exponential backoff; POST/PUT guarded by idempotency keys where applicable.
- **Abortable fetch**: timeouts and user-initiated cancel for uploads.
- **Prefetching**: on-hover/visible prefetch of likely next routes and data keys.
  **Tests**
- Latency injection with MSW to verify spinners/skeletons and cancel/abort behaviors.
- Optimistic update rollback test: forced server failure restores previous UI state.
  **Validation**
- Subjective feel: interactions seem instant; objective: Web Vitals within budget; error paths recover without data loss.

---

## Phase 9 — Internationalization & Theming Consistency

**Libraries**

- **react-i18next** (already used in sister projects).
- Intl APIs for date/number/plural; fallback polyfills if needed.
  **Functions / contracts**
- `t('namespace:key', { vars })` usage with explicit, descriptive keys.
- Currency/number/date formatters as wrapper utilities to standardize formatting.
- Theme tokens as a single source of truth; contrast checks (scripted) against WCAG AA.
  **Tests**
- Snapshot tests for key screens in both light/dark with token diffs.
- Formatting tests for pluralization and number/date locales.
  **Validation**
- Strings externalized; theme passes automated contrast check; RTL-safety spot check on core screens.

---

## Phase 10 — Observability, Security & Release Readiness

**Libraries**

- Error tracking: **Sentry** (or equivalent) with source maps.
- Sanitization: **DOMPurify** for any HTML serialization/render of editor output.
- CSP guidance (server-side; document the policy).
  **Functions / policies**
- **Error boundaries**: route-level and editor-level with friendly fallback and “copy details”.
- **Client logging**: `logClientError({ code, message, context })` throttle; opt-in breadcrumbs (sanitized, no PII).
- **Security checks**:

  - Validate all inputs client-side with Zod/AJV before sending.
  - Sanitize rich text on ingest and display; allowlist for marks/nodes.
  - Permission checks every write path; never trust client-side hide/disable alone.

- **Migrations**:

  - Versioned, idempotent; dry-run flag; record migration status.

- **Release discipline**:

  - Version bump + changelog; migration notes; upgrade guide; go/no-go checklist (green gates + budgets met).
    **Tests**

- Error boundary renders fallback on thrown child component; telemetry is called with redacted payload.
- XSS tests: paste malicious payload → sanitized output (no script execution) both save and render paths.
- Migration dry-run/effects tests with sample datasets.
  **Validation**
- Crashes captured with actionable context; no stored XSS vectors; release checklist green.

---

## Cross-Cutting Standards

**Contracts-first**

- Pick **Zod** _(form/input + client response validation, type inference)_ or **JSON Schema + AJV** _(cross-project parity with Q-Chess)_.

  - If Zod: generate JSON Schema for docs via `zod-to-json-schema`.
  - If AJV: generate TypeScript types via `json-schema-to-ts`.

- Maintain a single **roles/status/constants** module imported across UI, data, and tests.

**Data access layer**

- Prefer **RTK Query** for cache, memoized selectors, retries, and invalidation; treat queries/mutations as the one path to remote state.

**State shaping**

- Store UI state distinct from server cache; selectors derive view models (small pure functions, unit-tested).

**Security posture**

- Default-deny in permission checks; treat editor input as untrusted; output sanitize on every render path.

**Testing pyramid (target distributions)**

- Unit (\~60%): pure utils, selectors, reducers, permission guards.
- Component (\~30%): screens/components with RTL (+ axe).
- Integration/E2E (\~10%): happy-path create/edit/publish; blog switch; invite/accept.

**CI**

- Node LTS matrix (current + previous).
- Caching for package manager.
- Artifacts: coverage report, axe report, Web Vitals synthetic (if applicable), build output for preview.

---

## Example Function Signatures (illustrative, no filenames)

```ts
// Networking & validation
type Result<T> =
  | { ok: true; data: T }
  | { ok: false; error: { code: string; message: string; recoverable: boolean } };
function fetchJson<T>(
  input: RequestInfo,
  init?: RequestInit & { timeoutMs?: number },
): Promise<Result<T>>;

// Permissions
type Role = 'owner' | 'editor' | 'author';
function can(
  op: 'create' | 'edit' | 'publish' | 'manageMembers',
  ctx: { role: Role; userId: string; postOwnerId?: string },
): boolean;

// Blog management
function createBlog(input: {
  handle: string;
  title: string;
  visibility: 'public' | 'private';
}): Promise<Result<Blog>>;
function inviteMember(blogId: string, name: string, role: Role): Promise<Result<{ token: string }>>;
function savePost(
  postId: string,
  input: PostInput,
  opts: { ifMatchRevision: number },
): Promise<Result<{ revision: number }>>;
```

---

## Completion Bars (what “done” looks like per category)

- **Correctness:** zero suppressed type regions; known issues = empty; core flows never hard-crash.
- **Testability:** green typecheck/lint/tests on clean checkout; coverage trend up and stable; fast local watch.
- **Accessibility:** keyboard-only paths pass; axe shows no criticals; live region & focus rules verified.
- **Usability:** consistent patterns for empty/error; editor ergonomics predictable; no dead ends.
- **Security:** sanitized rich text; permission matrix enforced server- and client-side; no privilege escalation paths.
- **Performance:** web vitals within budget; optimistic updates/abortable fetches; graceful failure/retry.

---

**Assumptions & Risks:**
We can evolve API contracts to support multi-blog and roles; legacy data maps cleanly to default blogs; Slate output can be sanitized without losing required formatting; e2e scope remains minimal to avoid CI flake—expand only if signals require it.