diff --git a/skills/angular-best-practices/SKILL.md b/skills/angular-best-practices/SKILL.md
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+---
+name: angular-best-practices
+description: Angular performance optimization and best practices guide. Use when writing, reviewing, or refactoring Angular code for optimal performance, bundle size, and rendering efficiency.
+---
+
+# Angular Best Practices
+
+Comprehensive performance optimization guide for Angular applications. Contains prioritized rules for eliminating performance bottlenecks, optimizing bundles, and improving rendering.
+
+## When to Apply
+
+Reference these guidelines when:
+
+- Writing new Angular components or pages
+- Implementing data fetching patterns
+- Reviewing code for performance issues
+- Refactoring existing Angular code
+- Optimizing bundle size or load times
+- Configuring SSR/hydration
+
+---
+
+## Rule Categories by Priority
+
+| Priority | Category              | Impact     | Focus                           |
+| -------- | --------------------- | ---------- | ------------------------------- |
+| 1        | Change Detection      | CRITICAL   | Signals, OnPush, Zoneless       |
+| 2        | Bundle Optimization   | CRITICAL   | Lazy loading, tree shaking      |
+| 3        | Rendering Performance | HIGH       | @defer, trackBy, virtualization |
+| 4        | Server-Side Rendering | HIGH       | Hydration, prerendering         |
+| 5        | Template Optimization | MEDIUM     | Control flow, pipes             |
+| 6        | State Management      | MEDIUM     | Signal patterns, selectors      |
+| 7        | Memory Management     | LOW-MEDIUM | Cleanup, subscriptions          |
+
+---
+
+## 1. Change Detection (CRITICAL)
+
+### Use OnPush Change Detection
+
+```typescript
+// CORRECT - OnPush with Signals
+@Component({
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  template: `<div>{{ count() }}</div>`,
+})
+export class CounterComponent {
+  count = signal(0);
+}
+
+// WRONG - Default change detection
+@Component({
+  template: `<div>{{ count }}</div>`, // Checked every cycle
+})
+export class CounterComponent {
+  count = 0;
+}
+```
+
+### Prefer Signals Over Mutable Properties
+
+```typescript
+// CORRECT - Signals trigger precise updates
+@Component({
+  template: `
+    <h1>{{ title() }}</h1>
+    <p>Count: {{ count() }}</p>
+  `,
+})
+export class DashboardComponent {
+  title = signal("Dashboard");
+  count = signal(0);
+}
+
+// WRONG - Mutable properties require zone.js checks
+@Component({
+  template: `
+    <h1>{{ title }}</h1>
+    <p>Count: {{ count }}</p>
+  `,
+})
+export class DashboardComponent {
+  title = "Dashboard";
+  count = 0;
+}
+```
+
+### Enable Zoneless for New Projects
+
+```typescript
+// main.ts - Zoneless Angular (v20+)
+bootstrapApplication(AppComponent, {
+  providers: [provideZonelessChangeDetection()],
+});
+```
+
+**Benefits:**
+
+- No zone.js patches on async APIs
+- Smaller bundle (~15KB savings)
+- Clean stack traces for debugging
+- Better micro-frontend compatibility
+
+---
+
+## 2. Bundle Optimization (CRITICAL)
+
+### Lazy Load Routes
+
+```typescript
+// CORRECT - Lazy load feature routes
+export const routes: Routes = [
+  {
+    path: "admin",
+    loadChildren: () =>
+      import("./admin/admin.routes").then((m) => m.ADMIN_ROUTES),
+  },
+  {
+    path: "dashboard",
+    loadComponent: () =>
+      import("./dashboard/dashboard.component").then(
+        (m) => m.DashboardComponent,
+      ),
+  },
+];
+
+// WRONG - Eager loading everything
+import { AdminModule } from "./admin/admin.module";
+export const routes: Routes = [
+  { path: "admin", component: AdminComponent }, // In main bundle
+];
+```
+
+### Use @defer for Heavy Components
+
+```html
+<!-- CORRECT - Heavy component loads on demand -->
+@defer (on viewport) {
+<app-analytics-chart [data]="data()" />
+} @placeholder {
+<div class="chart-skeleton"></div>
+}
+
+<!-- WRONG - Heavy component in initial bundle -->
+<app-analytics-chart [data]="data()" />
+```
+
+### Avoid Barrel File Re-exports
+
+```typescript
+// WRONG - Imports entire barrel, breaks tree-shaking
+import { Button, Modal, Table } from "@shared/components";
+
+// CORRECT - Direct imports
+import { Button } from "@shared/components/button/button.component";
+import { Modal } from "@shared/components/modal/modal.component";
+```
+
+### Dynamic Import Third-Party Libraries
+
+```typescript
+// CORRECT - Load heavy library on demand
+async loadChart() {
+  const { Chart } = await import('chart.js');
+  this.chart = new Chart(this.canvas, config);
+}
+
+// WRONG - Bundle Chart.js in main chunk
+import { Chart } from 'chart.js';
+```
+
+---
+
+## 3. Rendering Performance (HIGH)
+
+### Always Use trackBy with @for
+
+```html
+<!-- CORRECT - Efficient DOM updates -->
+@for (item of items(); track item.id) {
+<app-item-card [item]="item" />
+}
+
+<!-- WRONG - Entire list re-renders on any change -->
+@for (item of items(); track $index) {
+<app-item-card [item]="item" />
+}
+```
+
+### Use Virtual Scrolling for Large Lists
+
+```typescript
+import { CdkVirtualScrollViewport, CdkFixedSizeVirtualScroll } from '@angular/cdk/scrolling';
+
+@Component({
+  imports: [CdkVirtualScrollViewport, CdkFixedSizeVirtualScroll],
+  template: `
+    <cdk-virtual-scroll-viewport itemSize="50" class="viewport">
+      <div *cdkVirtualFor="let item of items" class="item">
+        {{ item.name }}
+      </div>
+    </cdk-virtual-scroll-viewport>
+  `
+})
+```
+
+### Prefer Pure Pipes Over Methods
+
+```typescript
+// CORRECT - Pure pipe, memoized
+@Pipe({ name: 'filterActive', standalone: true, pure: true })
+export class FilterActivePipe implements PipeTransform {
+  transform(items: Item[]): Item[] {
+    return items.filter(i => i.active);
+  }
+}
+
+// Template
+@for (item of items() | filterActive; track item.id) { ... }
+
+// WRONG - Method called every change detection
+@for (item of getActiveItems(); track item.id) { ... }
+```
+
+### Use computed() for Derived Data
+
+```typescript
+// CORRECT - Computed, cached until dependencies change
+export class ProductStore {
+  products = signal<Product[]>([]);
+  filter = signal('');
+
+  filteredProducts = computed(() => {
+    const f = this.filter().toLowerCase();
+    return this.products().filter(p =>
+      p.name.toLowerCase().includes(f)
+    );
+  });
+}
+
+// WRONG - Recalculates every access
+get filteredProducts() {
+  return this.products.filter(p =>
+    p.name.toLowerCase().includes(this.filter)
+  );
+}
+```
+
+---
+
+## 4. Server-Side Rendering (HIGH)
+
+### Configure Incremental Hydration
+
+```typescript
+// app.config.ts
+import {
+  provideClientHydration,
+  withIncrementalHydration,
+} from "@angular/platform-browser";
+
+export const appConfig: ApplicationConfig = {
+  providers: [
+    provideClientHydration(withIncrementalHydration(), withEventReplay()),
+  ],
+};
+```
+
+### Defer Non-Critical Content
+
+```html
+<!-- Critical above-the-fold content -->
+<app-header />
+<app-hero />
+
+<!-- Below-fold deferred with hydration triggers -->
+@defer (hydrate on viewport) {
+<app-product-grid />
+} @defer (hydrate on interaction) {
+<app-chat-widget />
+}
+```
+
+### Use TransferState for SSR Data
+
+```typescript
+@Injectable({ providedIn: "root" })
+export class DataService {
+  private http = inject(HttpClient);
+  private transferState = inject(TransferState);
+  private platformId = inject(PLATFORM_ID);
+
+  getData(key: string): Observable<Data> {
+    const stateKey = makeStateKey<Data>(key);
+
+    if (isPlatformBrowser(this.platformId)) {
+      const cached = this.transferState.get(stateKey, null);
+      if (cached) {
+        this.transferState.remove(stateKey);
+        return of(cached);
+      }
+    }
+
+    return this.http.get<Data>(`/api/${key}`).pipe(
+      tap((data) => {
+        if (isPlatformServer(this.platformId)) {
+          this.transferState.set(stateKey, data);
+        }
+      }),
+    );
+  }
+}
+```
+
+---
+
+## 5. Template Optimization (MEDIUM)
+
+### Use New Control Flow Syntax
+
+```html
+<!-- CORRECT - New control flow (faster, smaller bundle) -->
+@if (user()) {
+<span>{{ user()!.name }}</span>
+} @else {
+<span>Guest</span>
+} @for (item of items(); track item.id) {
+<app-item [item]="item" />
+} @empty {
+<p>No items</p>
+}
+
+<!-- WRONG - Legacy structural directives -->
+<span *ngIf="user; else guest">{{ user.name }}</span>
+<ng-template #guest><span>Guest</span></ng-template>
+```
+
+### Avoid Complex Template Expressions
+
+```typescript
+// CORRECT - Precompute in component
+class Component {
+  items = signal<Item[]>([]);
+  sortedItems = computed(() =>
+    [...this.items()].sort((a, b) => a.name.localeCompare(b.name))
+  );
+}
+
+// Template
+@for (item of sortedItems(); track item.id) { ... }
+
+// WRONG - Sorting in template every render
+@for (item of items() | sort:'name'; track item.id) { ... }
+```
+
+---
+
+## 6. State Management (MEDIUM)
+
+### Use Selectors to Prevent Re-renders
+
+```typescript
+// CORRECT - Selective subscription
+@Component({
+  template: `<span>{{ userName() }}</span>`,
+})
+class HeaderComponent {
+  private store = inject(Store);
+  // Only re-renders when userName changes
+  userName = this.store.selectSignal(selectUserName);
+}
+
+// WRONG - Subscribing to entire state
+@Component({
+  template: `<span>{{ state().user.name }}</span>`,
+})
+class HeaderComponent {
+  private store = inject(Store);
+  // Re-renders on ANY state change
+  state = toSignal(this.store);
+}
+```
+
+### Colocate State with Features
+
+```typescript
+// CORRECT - Feature-scoped store
+@Injectable() // NOT providedIn: 'root'
+export class ProductStore { ... }
+
+@Component({
+  providers: [ProductStore], // Scoped to component tree
+})
+export class ProductPageComponent {
+  store = inject(ProductStore);
+}
+
+// WRONG - Everything in global store
+@Injectable({ providedIn: 'root' })
+export class GlobalStore {
+  // Contains ALL app state - hard to tree-shake
+}
+```
+
+---
+
+## 7. Memory Management (LOW-MEDIUM)
+
+### Use takeUntilDestroyed for Subscriptions
+
+```typescript
+import { takeUntilDestroyed } from '@angular/core/rxjs-interop';
+
+@Component({...})
+export class DataComponent {
+  private destroyRef = inject(DestroyRef);
+
+  constructor() {
+    this.data$.pipe(
+      takeUntilDestroyed(this.destroyRef)
+    ).subscribe(data => this.process(data));
+  }
+}
+
+// WRONG - Manual subscription management
+export class DataComponent implements OnDestroy {
+  private subscription!: Subscription;
+
+  ngOnInit() {
+    this.subscription = this.data$.subscribe(...);
+  }
+
+  ngOnDestroy() {
+    this.subscription.unsubscribe(); // Easy to forget
+  }
+}
+```
+
+### Prefer Signals Over Subscriptions
+
+```typescript
+// CORRECT - No subscription needed
+@Component({
+  template: `<div>{{ data().name }}</div>`,
+})
+export class Component {
+  data = toSignal(this.service.data$, { initialValue: null });
+}
+
+// WRONG - Manual subscription
+@Component({
+  template: `<div>{{ data?.name }}</div>`,
+})
+export class Component implements OnInit, OnDestroy {
+  data: Data | null = null;
+  private sub!: Subscription;
+
+  ngOnInit() {
+    this.sub = this.service.data$.subscribe((d) => (this.data = d));
+  }
+
+  ngOnDestroy() {
+    this.sub.unsubscribe();
+  }
+}
+```
+
+---
+
+## Quick Reference Checklist
+
+### New Component
+
+- [ ] `changeDetection: ChangeDetectionStrategy.OnPush`
+- [ ] `standalone: true`
+- [ ] Signals for state (`signal()`, `input()`, `output()`)
+- [ ] `inject()` for dependencies
+- [ ] `@for` with `track` expression
+
+### Performance Review
+
+- [ ] No methods in templates (use pipes or computed)
+- [ ] Large lists virtualized
+- [ ] Heavy components deferred
+- [ ] Routes lazy-loaded
+- [ ] Third-party libs dynamically imported
+
+### SSR Check
+
+- [ ] Hydration configured
+- [ ] Critical content renders first
+- [ ] Non-critical content uses `@defer (hydrate on ...)`
+- [ ] TransferState for server-fetched data
+
+---
+
+## Resources
+
+- [Angular Performance Guide](https://angular.dev/best-practices/performance)
+- [Zoneless Angular](https://angular.dev/guide/experimental/zoneless)
+- [Angular SSR Guide](https://angular.dev/guide/ssr)
+- [Change Detection Deep Dive](https://angular.dev/guide/change-detection)
diff --git a/skills/angular-state-management/SKILL.md b/skills/angular-state-management/SKILL.md
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+---
+name: angular-state-management
+description: Master modern Angular state management with Signals, NgRx, and RxJS. Use when setting up global state, managing component stores, choosing between state solutions, or migrating from legacy patterns.
+---
+
+# Angular State Management
+
+Comprehensive guide to modern Angular state management patterns, from Signal-based local state to global stores and server state synchronization.
+
+## When to Use This Skill
+
+- Setting up global state management in Angular
+- Choosing between Signals, NgRx, or Akita
+- Managing component-level stores
+- Implementing optimistic updates
+- Debugging state-related issues
+- Migrating from legacy state patterns
+
+## Do Not Use This Skill When
+
+- The task is unrelated to Angular state management
+- You need React state management → use `react-state-management`
+
+---
+
+## Core Concepts
+
+### State Categories
+
+| Type             | Description                  | Solutions             |
+| ---------------- | ---------------------------- | --------------------- |
+| **Local State**  | Component-specific, UI state | Signals, `signal()`   |
+| **Shared State** | Between related components   | Signal services       |
+| **Global State** | App-wide, complex            | NgRx, Akita, Elf      |
+| **Server State** | Remote data, caching         | NgRx Query, RxAngular |
+| **URL State**    | Route parameters             | ActivatedRoute        |
+| **Form State**   | Input values, validation     | Reactive Forms        |
+
+### Selection Criteria
+
+```
+Small app, simple state → Signal Services
+Medium app, moderate state → Component Stores
+Large app, complex state → NgRx Store
+Heavy server interaction → NgRx Query + Signal Services
+Real-time updates → RxAngular + Signals
+```
+
+---
+
+## Quick Start: Signal-Based State
+
+### Pattern 1: Simple Signal Service
+
+```typescript
+// services/counter.service.ts
+import { Injectable, signal, computed } from "@angular/core";
+
+@Injectable({ providedIn: "root" })
+export class CounterService {
+  // Private writable signals
+  private _count = signal(0);
+
+  // Public read-only
+  readonly count = this._count.asReadonly();
+  readonly doubled = computed(() => this._count() * 2);
+  readonly isPositive = computed(() => this._count() > 0);
+
+  increment() {
+    this._count.update((v) => v + 1);
+  }
+
+  decrement() {
+    this._count.update((v) => v - 1);
+  }
+
+  reset() {
+    this._count.set(0);
+  }
+}
+
+// Usage in component
+@Component({
+  template: `
+    <p>Count: {{ counter.count() }}</p>
+    <p>Doubled: {{ counter.doubled() }}</p>
+    <button (click)="counter.increment()">+</button>
+  `,
+})
+export class CounterComponent {
+  counter = inject(CounterService);
+}
+```
+
+### Pattern 2: Feature Signal Store
+
+```typescript
+// stores/user.store.ts
+import { Injectable, signal, computed, inject } from "@angular/core";
+import { HttpClient } from "@angular/common/http";
+import { toSignal } from "@angular/core/rxjs-interop";
+
+interface User {
+  id: string;
+  name: string;
+  email: string;
+}
+
+interface UserState {
+  user: User | null;
+  loading: boolean;
+  error: string | null;
+}
+
+@Injectable({ providedIn: "root" })
+export class UserStore {
+  private http = inject(HttpClient);
+
+  // State signals
+  private _user = signal<User | null>(null);
+  private _loading = signal(false);
+  private _error = signal<string | null>(null);
+
+  // Selectors (read-only computed)
+  readonly user = computed(() => this._user());
+  readonly loading = computed(() => this._loading());
+  readonly error = computed(() => this._error());
+  readonly isAuthenticated = computed(() => this._user() !== null);
+  readonly displayName = computed(() => this._user()?.name ?? "Guest");
+
+  // Actions
+  async loadUser(id: string) {
+    this._loading.set(true);
+    this._error.set(null);
+
+    try {
+      const user = await fetch(`/api/users/${id}`).then((r) => r.json());
+      this._user.set(user);
+    } catch (e) {
+      this._error.set("Failed to load user");
+    } finally {
+      this._loading.set(false);
+    }
+  }
+
+  updateUser(updates: Partial<User>) {
+    this._user.update((user) => (user ? { ...user, ...updates } : null));
+  }
+
+  logout() {
+    this._user.set(null);
+    this._error.set(null);
+  }
+}
+```
+
+### Pattern 3: SignalStore (NgRx Signals)
+
+```typescript
+// stores/products.store.ts
+import {
+  signalStore,
+  withState,
+  withMethods,
+  withComputed,
+  patchState,
+} from "@ngrx/signals";
+import { inject } from "@angular/core";
+import { ProductService } from "./product.service";
+
+interface ProductState {
+  products: Product[];
+  loading: boolean;
+  filter: string;
+}
+
+const initialState: ProductState = {
+  products: [],
+  loading: false,
+  filter: "",
+};
+
+export const ProductStore = signalStore(
+  { providedIn: "root" },
+
+  withState(initialState),
+
+  withComputed((store) => ({
+    filteredProducts: computed(() => {
+      const filter = store.filter().toLowerCase();
+      return store
+        .products()
+        .filter((p) => p.name.toLowerCase().includes(filter));
+    }),
+    totalCount: computed(() => store.products().length),
+  })),
+
+  withMethods((store, productService = inject(ProductService)) => ({
+    async loadProducts() {
+      patchState(store, { loading: true });
+
+      try {
+        const products = await productService.getAll();
+        patchState(store, { products, loading: false });
+      } catch {
+        patchState(store, { loading: false });
+      }
+    },
+
+    setFilter(filter: string) {
+      patchState(store, { filter });
+    },
+
+    addProduct(product: Product) {
+      patchState(store, ({ products }) => ({
+        products: [...products, product],
+      }));
+    },
+  })),
+);
+
+// Usage
+@Component({
+  template: `
+    <input (input)="store.setFilter($event.target.value)" />
+    @if (store.loading()) {
+      <app-spinner />
+    } @else {
+      @for (product of store.filteredProducts(); track product.id) {
+        <app-product-card [product]="product" />
+      }
+    }
+  `,
+})
+export class ProductListComponent {
+  store = inject(ProductStore);
+
+  ngOnInit() {
+    this.store.loadProducts();
+  }
+}
+```
+
+---
+
+## NgRx Store (Global State)
+
+### Setup
+
+```typescript
+// store/app.state.ts
+import { ActionReducerMap } from "@ngrx/store";
+
+export interface AppState {
+  user: UserState;
+  cart: CartState;
+}
+
+export const reducers: ActionReducerMap<AppState> = {
+  user: userReducer,
+  cart: cartReducer,
+};
+
+// main.ts
+bootstrapApplication(AppComponent, {
+  providers: [
+    provideStore(reducers),
+    provideEffects([UserEffects, CartEffects]),
+    provideStoreDevtools({ maxAge: 25 }),
+  ],
+});
+```
+
+### Feature Slice Pattern
+
+```typescript
+// store/user/user.actions.ts
+import { createActionGroup, props, emptyProps } from "@ngrx/store";
+
+export const UserActions = createActionGroup({
+  source: "User",
+  events: {
+    "Load User": props<{ userId: string }>(),
+    "Load User Success": props<{ user: User }>(),
+    "Load User Failure": props<{ error: string }>(),
+    "Update User": props<{ updates: Partial<User> }>(),
+    Logout: emptyProps(),
+  },
+});
+```
+
+```typescript
+// store/user/user.reducer.ts
+import { createReducer, on } from "@ngrx/store";
+import { UserActions } from "./user.actions";
+
+export interface UserState {
+  user: User | null;
+  loading: boolean;
+  error: string | null;
+}
+
+const initialState: UserState = {
+  user: null,
+  loading: false,
+  error: null,
+};
+
+export const userReducer = createReducer(
+  initialState,
+
+  on(UserActions.loadUser, (state) => ({
+    ...state,
+    loading: true,
+    error: null,
+  })),
+
+  on(UserActions.loadUserSuccess, (state, { user }) => ({
+    ...state,
+    user,
+    loading: false,
+  })),
+
+  on(UserActions.loadUserFailure, (state, { error }) => ({
+    ...state,
+    loading: false,
+    error,
+  })),
+
+  on(UserActions.logout, () => initialState),
+);
+```
+
+```typescript
+// store/user/user.selectors.ts
+import { createFeatureSelector, createSelector } from "@ngrx/store";
+import { UserState } from "./user.reducer";
+
+export const selectUserState = createFeatureSelector<UserState>("user");
+
+export const selectUser = createSelector(
+  selectUserState,
+  (state) => state.user,
+);
+
+export const selectUserLoading = createSelector(
+  selectUserState,
+  (state) => state.loading,
+);
+
+export const selectIsAuthenticated = createSelector(
+  selectUser,
+  (user) => user !== null,
+);
+```
+
+```typescript
+// store/user/user.effects.ts
+import { Injectable, inject } from "@angular/core";
+import { Actions, createEffect, ofType } from "@ngrx/effects";
+import { switchMap, map, catchError, of } from "rxjs";
+
+@Injectable()
+export class UserEffects {
+  private actions$ = inject(Actions);
+  private userService = inject(UserService);
+
+  loadUser$ = createEffect(() =>
+    this.actions$.pipe(
+      ofType(UserActions.loadUser),
+      switchMap(({ userId }) =>
+        this.userService.getUser(userId).pipe(
+          map((user) => UserActions.loadUserSuccess({ user })),
+          catchError((error) =>
+            of(UserActions.loadUserFailure({ error: error.message })),
+          ),
+        ),
+      ),
+    ),
+  );
+}
+```
+
+### Component Usage
+
+```typescript
+@Component({
+  template: `
+    @if (loading()) {
+      <app-spinner />
+    } @else if (user(); as user) {
+      <h1>Welcome, {{ user.name }}</h1>
+      <button (click)="logout()">Logout</button>
+    }
+  `,
+})
+export class HeaderComponent {
+  private store = inject(Store);
+
+  user = this.store.selectSignal(selectUser);
+  loading = this.store.selectSignal(selectUserLoading);
+
+  logout() {
+    this.store.dispatch(UserActions.logout());
+  }
+}
+```
+
+---
+
+## RxJS-Based Patterns
+
+### Component Store (Local Feature State)
+
+```typescript
+// stores/todo.store.ts
+import { Injectable } from "@angular/core";
+import { ComponentStore } from "@ngrx/component-store";
+import { switchMap, tap, catchError, EMPTY } from "rxjs";
+
+interface TodoState {
+  todos: Todo[];
+  loading: boolean;
+}
+
+@Injectable()
+export class TodoStore extends ComponentStore<TodoState> {
+  constructor(private todoService: TodoService) {
+    super({ todos: [], loading: false });
+  }
+
+  // Selectors
+  readonly todos$ = this.select((state) => state.todos);
+  readonly loading$ = this.select((state) => state.loading);
+  readonly completedCount$ = this.select(
+    this.todos$,
+    (todos) => todos.filter((t) => t.completed).length,
+  );
+
+  // Updaters
+  readonly addTodo = this.updater((state, todo: Todo) => ({
+    ...state,
+    todos: [...state.todos, todo],
+  }));
+
+  readonly toggleTodo = this.updater((state, id: string) => ({
+    ...state,
+    todos: state.todos.map((t) =>
+      t.id === id ? { ...t, completed: !t.completed } : t,
+    ),
+  }));
+
+  // Effects
+  readonly loadTodos = this.effect<void>((trigger$) =>
+    trigger$.pipe(
+      tap(() => this.patchState({ loading: true })),
+      switchMap(() =>
+        this.todoService.getAll().pipe(
+          tap({
+            next: (todos) => this.patchState({ todos, loading: false }),
+            error: () => this.patchState({ loading: false }),
+          }),
+          catchError(() => EMPTY),
+        ),
+      ),
+    ),
+  );
+}
+```
+
+---
+
+## Server State with Signals
+
+### HTTP + Signals Pattern
+
+```typescript
+// services/api.service.ts
+import { Injectable, signal, inject } from "@angular/core";
+import { HttpClient } from "@angular/common/http";
+import { toSignal } from "@angular/core/rxjs-interop";
+
+interface ApiState<T> {
+  data: T | null;
+  loading: boolean;
+  error: string | null;
+}
+
+@Injectable({ providedIn: "root" })
+export class ProductApiService {
+  private http = inject(HttpClient);
+
+  private _state = signal<ApiState<Product[]>>({
+    data: null,
+    loading: false,
+    error: null,
+  });
+
+  readonly products = computed(() => this._state().data ?? []);
+  readonly loading = computed(() => this._state().loading);
+  readonly error = computed(() => this._state().error);
+
+  async fetchProducts(): Promise<void> {
+    this._state.update((s) => ({ ...s, loading: true, error: null }));
+
+    try {
+      const data = await firstValueFrom(
+        this.http.get<Product[]>("/api/products"),
+      );
+      this._state.update((s) => ({ ...s, data, loading: false }));
+    } catch (e) {
+      this._state.update((s) => ({
+        ...s,
+        loading: false,
+        error: "Failed to fetch products",
+      }));
+    }
+  }
+
+  // Optimistic update
+  async deleteProduct(id: string): Promise<void> {
+    const previousData = this._state().data;
+
+    // Optimistically remove
+    this._state.update((s) => ({
+      ...s,
+      data: s.data?.filter((p) => p.id !== id) ?? null,
+    }));
+
+    try {
+      await firstValueFrom(this.http.delete(`/api/products/${id}`));
+    } catch {
+      // Rollback on error
+      this._state.update((s) => ({ ...s, data: previousData }));
+    }
+  }
+}
+```
+
+---
+
+## Best Practices
+
+### Do's
+
+| Practice                           | Why                                |
+| ---------------------------------- | ---------------------------------- |
+| Use Signals for local state        | Simple, reactive, no subscriptions |
+| Use `computed()` for derived data  | Auto-updates, memoized             |
+| Colocate state with feature        | Easier to maintain                 |
+| Use NgRx for complex flows         | Actions, effects, devtools         |
+| Prefer `inject()` over constructor | Cleaner, works in factories        |
+
+### Don'ts
+
+| Anti-Pattern                      | Instead                                               |
+| --------------------------------- | ----------------------------------------------------- |
+| Store derived data                | Use `computed()`                                      |
+| Mutate signals directly           | Use `set()` or `update()`                             |
+| Over-globalize state              | Keep local when possible                              |
+| Mix RxJS and Signals chaotically  | Choose primary, bridge with `toSignal`/`toObservable` |
+| Subscribe in components for state | Use template with signals                             |
+
+---
+
+## Migration Path
+
+### From BehaviorSubject to Signals
+
+```typescript
+// Before: RxJS-based
+@Injectable({ providedIn: "root" })
+export class OldUserService {
+  private userSubject = new BehaviorSubject<User | null>(null);
+  user$ = this.userSubject.asObservable();
+
+  setUser(user: User) {
+    this.userSubject.next(user);
+  }
+}
+
+// After: Signal-based
+@Injectable({ providedIn: "root" })
+export class UserService {
+  private _user = signal<User | null>(null);
+  readonly user = this._user.asReadonly();
+
+  setUser(user: User) {
+    this._user.set(user);
+  }
+}
+```
+
+### Bridging Signals and RxJS
+
+```typescript
+import { toSignal, toObservable } from '@angular/core/rxjs-interop';
+
+// Observable → Signal
+@Component({...})
+export class ExampleComponent {
+  private route = inject(ActivatedRoute);
+
+  // Convert Observable to Signal
+  userId = toSignal(
+    this.route.params.pipe(map(p => p['id'])),
+    { initialValue: '' }
+  );
+}
+
+// Signal → Observable
+export class DataService {
+  private filter = signal('');
+
+  // Convert Signal to Observable
+  filter$ = toObservable(this.filter);
+
+  filteredData$ = this.filter$.pipe(
+    debounceTime(300),
+    switchMap(filter => this.http.get(`/api/data?q=${filter}`))
+  );
+}
+```
+
+---
+
+## Resources
+
+- [Angular Signals Guide](https://angular.dev/guide/signals)
+- [NgRx Documentation](https://ngrx.io/)
+- [NgRx SignalStore](https://ngrx.io/guide/signals)
+- [RxAngular](https://www.rx-angular.io/)
diff --git a/skills/angular-ui-patterns/SKILL.md b/skills/angular-ui-patterns/SKILL.md
new file mode 100644
index 00000000..cc9601cd
--- /dev/null
+++ b/skills/angular-ui-patterns/SKILL.md
@@ -0,0 +1,506 @@
+---
+name: angular-ui-patterns
+description: Modern Angular UI patterns for loading states, error handling, and data display. Use when building UI components, handling async data, or managing component states.
+---
+
+# Angular UI Patterns
+
+## Core Principles
+
+1. **Never show stale UI** - Loading states only when actually loading
+2. **Always surface errors** - Users must know when something fails
+3. **Optimistic updates** - Make the UI feel instant
+4. **Progressive disclosure** - Use `@defer` to show content as available
+5. **Graceful degradation** - Partial data is better than no data
+
+---
+
+## Loading State Patterns
+
+### The Golden Rule
+
+**Show loading indicator ONLY when there's no data to display.**
+
+```typescript
+@Component({
+  template: `
+    @if (error()) {
+      <app-error-state [error]="error()" (retry)="load()" />
+    } @else if (loading() && !items().length) {
+      <app-skeleton-list />
+    } @else if (!items().length) {
+      <app-empty-state message="No items found" />
+    } @else {
+      <app-item-list [items]="items()" />
+    }
+  `,
+})
+export class ItemListComponent {
+  private store = inject(ItemStore);
+
+  items = this.store.items;
+  loading = this.store.loading;
+  error = this.store.error;
+}
+```
+
+### Loading State Decision Tree
+
+```
+Is there an error?
+  → Yes: Show error state with retry option
+  → No: Continue
+
+Is it loading AND we have no data?
+  → Yes: Show loading indicator (spinner/skeleton)
+  → No: Continue
+
+Do we have data?
+  → Yes, with items: Show the data
+  → Yes, but empty: Show empty state
+  → No: Show loading (fallback)
+```
+
+### Skeleton vs Spinner
+
+| Use Skeleton When    | Use Spinner When      |
+| -------------------- | --------------------- |
+| Known content shape  | Unknown content shape |
+| List/card layouts    | Modal actions         |
+| Initial page load    | Button submissions    |
+| Content placeholders | Inline operations     |
+
+---
+
+## Control Flow Patterns
+
+### @if/@else for Conditional Rendering
+
+```html
+@if (user(); as user) {
+<span>Welcome, {{ user.name }}</span>
+} @else if (loading()) {
+<app-spinner size="small" />
+} @else {
+<a routerLink="/login">Sign In</a>
+}
+```
+
+### @for with Track
+
+```html
+@for (item of items(); track item.id) {
+<app-item-card [item]="item" (delete)="remove(item.id)" />
+} @empty {
+<app-empty-state
+  icon="inbox"
+  message="No items yet"
+  actionLabel="Create Item"
+  (action)="create()"
+/>
+}
+```
+
+### @defer for Progressive Loading
+
+```html
+<!-- Critical content loads immediately -->
+<app-header />
+<app-hero-section />
+
+<!-- Non-critical content deferred -->
+@defer (on viewport) {
+<app-comments [postId]="postId()" />
+} @placeholder {
+<div class="h-32 bg-gray-100 animate-pulse"></div>
+} @loading (minimum 200ms) {
+<app-spinner />
+} @error {
+<app-error-state message="Failed to load comments" />
+}
+```
+
+---
+
+## Error Handling Patterns
+
+### Error Handling Hierarchy
+
+```
+1. Inline error (field-level) → Form validation errors
+2. Toast notification → Recoverable errors, user can retry
+3. Error banner → Page-level errors, data still partially usable
+4. Full error screen → Unrecoverable, needs user action
+```
+
+### Always Show Errors
+
+**CRITICAL: Never swallow errors silently.**
+
+```typescript
+// CORRECT - Error always surfaced to user
+@Component({...})
+export class CreateItemComponent {
+  private store = inject(ItemStore);
+  private toast = inject(ToastService);
+
+  async create(data: CreateItemDto) {
+    try {
+      await this.store.create(data);
+      this.toast.success('Item created successfully');
+      this.router.navigate(['/items']);
+    } catch (error) {
+      console.error('createItem failed:', error);
+      this.toast.error('Failed to create item. Please try again.');
+    }
+  }
+}
+
+// WRONG - Error silently caught
+async create(data: CreateItemDto) {
+  try {
+    await this.store.create(data);
+  } catch (error) {
+    console.error(error); // User sees nothing!
+  }
+}
+```
+
+### Error State Component Pattern
+
+```typescript
+@Component({
+  selector: "app-error-state",
+  standalone: true,
+  imports: [NgOptimizedImage],
+  template: `
+    <div class="error-state">
+      <img ngSrc="/assets/error-icon.svg" width="64" height="64" alt="" />
+      <h3>{{ title() }}</h3>
+      <p>{{ message() }}</p>
+      @if (retry.observed) {
+        <button (click)="retry.emit()" class="btn-primary">Try Again</button>
+      }
+    </div>
+  `,
+})
+export class ErrorStateComponent {
+  title = input("Something went wrong");
+  message = input("An unexpected error occurred");
+  retry = output<void>();
+}
+```
+
+---
+
+## Button State Patterns
+
+### Button Loading State
+
+```html
+<button
+  (click)="handleSubmit()"
+  [disabled]="isSubmitting() || !form.valid"
+  class="btn-primary"
+>
+  @if (isSubmitting()) {
+  <app-spinner size="small" class="mr-2" />
+  Saving... } @else { Save Changes }
+</button>
+```
+
+### Disable During Operations
+
+**CRITICAL: Always disable triggers during async operations.**
+
+```typescript
+// CORRECT - Button disabled while loading
+@Component({
+  template: `
+    <button
+      [disabled]="saving()"
+      (click)="save()"
+    >
+      @if (saving()) {
+        <app-spinner size="sm" /> Saving...
+      } @else {
+        Save
+      }
+    </button>
+  `
+})
+export class SaveButtonComponent {
+  saving = signal(false);
+
+  async save() {
+    this.saving.set(true);
+    try {
+      await this.service.save();
+    } finally {
+      this.saving.set(false);
+    }
+  }
+}
+
+// WRONG - User can click multiple times
+<button (click)="save()">
+  {{ saving() ? 'Saving...' : 'Save' }}
+</button>
+```
+
+---
+
+## Empty States
+
+### Empty State Requirements
+
+Every list/collection MUST have an empty state:
+
+```html
+@for (item of items(); track item.id) {
+<app-item-card [item]="item" />
+} @empty {
+<app-empty-state
+  icon="folder-open"
+  title="No items yet"
+  description="Create your first item to get started"
+  actionLabel="Create Item"
+  (action)="openCreateDialog()"
+/>
+}
+```
+
+### Contextual Empty States
+
+```typescript
+@Component({
+  selector: "app-empty-state",
+  template: `
+    <div class="empty-state">
+      <span class="icon" [class]="icon()"></span>
+      <h3>{{ title() }}</h3>
+      <p>{{ description() }}</p>
+      @if (actionLabel()) {
+        <button (click)="action.emit()" class="btn-primary">
+          {{ actionLabel() }}
+        </button>
+      }
+    </div>
+  `,
+})
+export class EmptyStateComponent {
+  icon = input("inbox");
+  title = input.required<string>();
+  description = input("");
+  actionLabel = input<string | null>(null);
+  action = output<void>();
+}
+```
+
+---
+
+## Form Patterns
+
+### Form with Loading and Validation
+
+```typescript
+@Component({
+  template: `
+    <form [formGroup]="form" (ngSubmit)="onSubmit()">
+      <div class="form-field">
+        <label for="name">Name</label>
+        <input
+          id="name"
+          formControlName="name"
+          [class.error]="isFieldInvalid('name')"
+        />
+        @if (isFieldInvalid("name")) {
+          <span class="error-text">
+            {{ getFieldError("name") }}
+          </span>
+        }
+      </div>
+
+      <div class="form-field">
+        <label for="email">Email</label>
+        <input id="email" type="email" formControlName="email" />
+        @if (isFieldInvalid("email")) {
+          <span class="error-text">
+            {{ getFieldError("email") }}
+          </span>
+        }
+      </div>
+
+      <button type="submit" [disabled]="form.invalid || submitting()">
+        @if (submitting()) {
+          <app-spinner size="sm" /> Submitting...
+        } @else {
+          Submit
+        }
+      </button>
+    </form>
+  `,
+})
+export class UserFormComponent {
+  private fb = inject(FormBuilder);
+
+  submitting = signal(false);
+
+  form = this.fb.group({
+    name: ["", [Validators.required, Validators.minLength(2)]],
+    email: ["", [Validators.required, Validators.email]],
+  });
+
+  isFieldInvalid(field: string): boolean {
+    const control = this.form.get(field);
+    return control ? control.invalid && control.touched : false;
+  }
+
+  getFieldError(field: string): string {
+    const control = this.form.get(field);
+    if (control?.hasError("required")) return "This field is required";
+    if (control?.hasError("email")) return "Invalid email format";
+    if (control?.hasError("minlength")) return "Too short";
+    return "";
+  }
+
+  async onSubmit() {
+    if (this.form.invalid) return;
+
+    this.submitting.set(true);
+    try {
+      await this.service.submit(this.form.value);
+      this.toast.success("Submitted successfully");
+    } catch {
+      this.toast.error("Submission failed");
+    } finally {
+      this.submitting.set(false);
+    }
+  }
+}
+```
+
+---
+
+## Dialog/Modal Patterns
+
+### Confirmation Dialog
+
+```typescript
+// dialog.service.ts
+@Injectable({ providedIn: 'root' })
+export class DialogService {
+  private dialog = inject(Dialog); // CDK Dialog or custom
+
+  async confirm(options: {
+    title: string;
+    message: string;
+    confirmText?: string;
+    cancelText?: string;
+  }): Promise<boolean> {
+    const dialogRef = this.dialog.open(ConfirmDialogComponent, {
+      data: options,
+    });
+
+    return await firstValueFrom(dialogRef.closed) ?? false;
+  }
+}
+
+// Usage
+async deleteItem(item: Item) {
+  const confirmed = await this.dialog.confirm({
+    title: 'Delete Item',
+    message: `Are you sure you want to delete "${item.name}"?`,
+    confirmText: 'Delete',
+  });
+
+  if (confirmed) {
+    await this.store.delete(item.id);
+  }
+}
+```
+
+---
+
+## Anti-Patterns
+
+### Loading States
+
+```typescript
+// WRONG - Spinner when data exists (causes flash on refetch)
+@if (loading()) {
+  <app-spinner />
+}
+
+// CORRECT - Only show loading without data
+@if (loading() && !items().length) {
+  <app-spinner />
+}
+```
+
+### Error Handling
+
+```typescript
+// WRONG - Error swallowed
+try {
+  await this.service.save();
+} catch (e) {
+  console.log(e); // User has no idea!
+}
+
+// CORRECT - Error surfaced
+try {
+  await this.service.save();
+} catch (e) {
+  console.error("Save failed:", e);
+  this.toast.error("Failed to save. Please try again.");
+}
+```
+
+### Button States
+
+```html
+<!-- WRONG - Button not disabled during submission -->
+<button (click)="submit()">Submit</button>
+
+<!-- CORRECT - Disabled and shows loading -->
+<button (click)="submit()" [disabled]="loading()">
+  @if (loading()) {
+  <app-spinner size="sm" />
+  } Submit
+</button>
+```
+
+---
+
+## UI State Checklist
+
+Before completing any UI component:
+
+### UI States
+
+- [ ] Error state handled and shown to user
+- [ ] Loading state shown only when no data exists
+- [ ] Empty state provided for collections (`@empty` block)
+- [ ] Buttons disabled during async operations
+- [ ] Buttons show loading indicator when appropriate
+
+### Data & Mutations
+
+- [ ] All async operations have error handling
+- [ ] All user actions have feedback (toast/visual)
+- [ ] Optimistic updates rollback on failure
+
+### Accessibility
+
+- [ ] Loading states announced to screen readers
+- [ ] Error messages linked to form fields
+- [ ] Focus management after state changes
+
+---
+
+## Integration with Other Skills
+
+- **angular-state-management**: Use Signal stores for state
+- **angular**: Apply modern patterns (Signals, @defer)
+- **testing-patterns**: Test all UI states
diff --git a/skills/angular/SKILL.md b/skills/angular/SKILL.md
new file mode 100644
index 00000000..fa377d6a
--- /dev/null
+++ b/skills/angular/SKILL.md
@@ -0,0 +1,763 @@
+---
+name: angular
+description: >-
+  Modern Angular (v20+) expert with deep knowledge of Signals, Standalone
+  Components, Zoneless applications, SSR/Hydration, and reactive patterns.
+  Use PROACTIVELY for Angular development, component architecture, state
+  management, performance optimization, and migration to modern patterns.
+---
+
+# Angular Expert
+
+Master modern Angular development with Signals, Standalone Components, Zoneless applications, SSR/Hydration, and the latest reactive patterns.
+
+## When to Use This Skill
+
+- Building new Angular applications (v20+)
+- Implementing Signals-based reactive patterns
+- Creating Standalone Components and migrating from NgModules
+- Configuring Zoneless Angular applications
+- Implementing SSR, prerendering, and hydration
+- Optimizing Angular performance
+- Adopting modern Angular patterns and best practices
+
+## Do Not Use This Skill When
+
+- Migrating from AngularJS (1.x) → use `angular-migration` skill
+- Working with legacy Angular apps that cannot upgrade
+- General TypeScript issues → use `typescript-expert` skill
+
+## Instructions
+
+1. Assess the Angular version and project structure
+2. Apply modern patterns (Signals, Standalone, Zoneless)
+3. Implement with proper typing and reactivity
+4. Validate with build and tests
+
+## Safety
+
+- Always test changes in development before production
+- Gradual migration for existing apps (don't big-bang refactor)
+- Keep backward compatibility during transitions
+
+---
+
+## Angular Version Timeline
+
+| Version        | Release | Key Features                                           |
+| -------------- | ------- | ------------------------------------------------------ |
+| **Angular 20** | Q2 2025 | Signals stable, Zoneless stable, Incremental hydration |
+| **Angular 21** | Q4 2025 | Signals-first default, Enhanced SSR                    |
+| **Angular 22** | Q2 2026 | Signal Forms, Selectorless components                  |
+
+---
+
+## 1. Signals: The New Reactive Primitive
+
+Signals are Angular's fine-grained reactivity system, replacing zone.js-based change detection.
+
+### Core Concepts
+
+```typescript
+import { signal, computed, effect } from "@angular/core";
+
+// Writable signal
+const count = signal(0);
+
+// Read value
+console.log(count()); // 0
+
+// Update value
+count.set(5); // Direct set
+count.update((v) => v + 1); // Functional update
+
+// Computed (derived) signal
+const doubled = computed(() => count() * 2);
+
+// Effect (side effects)
+effect(() => {
+  console.log(`Count changed to: ${count()}`);
+});
+```
+
+### Signal-Based Inputs and Outputs
+
+```typescript
+import { Component, input, output, model } from "@angular/core";
+
+@Component({
+  selector: "app-user-card",
+  standalone: true,
+  template: `
+    <div class="card">
+      <h3>{{ name() }}</h3>
+      <span>{{ role() }}</span>
+      <button (click)="select.emit(id())">Select</button>
+    </div>
+  `,
+})
+export class UserCardComponent {
+  // Signal inputs (read-only)
+  id = input.required<string>();
+  name = input.required<string>();
+  role = input<string>("User"); // With default
+
+  // Output
+  select = output<string>();
+
+  // Two-way binding (model)
+  isSelected = model(false);
+}
+
+// Usage:
+// <app-user-card [id]="'123'" [name]="'John'" [(isSelected)]="selected" />
+```
+
+### Signal Queries (ViewChild/ContentChild)
+
+```typescript
+import {
+  Component,
+  viewChild,
+  viewChildren,
+  contentChild,
+} from "@angular/core";
+
+@Component({
+  selector: "app-container",
+  standalone: true,
+  template: `
+    <input #searchInput />
+    <app-item *ngFor="let item of items()" />
+  `,
+})
+export class ContainerComponent {
+  // Signal-based queries
+  searchInput = viewChild<ElementRef>("searchInput");
+  items = viewChildren(ItemComponent);
+  projectedContent = contentChild(HeaderDirective);
+
+  focusSearch() {
+    this.searchInput()?.nativeElement.focus();
+  }
+}
+```
+
+### When to Use Signals vs RxJS
+
+| Use Case                | Signals         | RxJS                             |
+| ----------------------- | --------------- | -------------------------------- |
+| Local component state   | ✅ Preferred    | Overkill                         |
+| Derived/computed values | ✅ `computed()` | `combineLatest` works            |
+| Side effects            | ✅ `effect()`   | `tap` operator                   |
+| HTTP requests           | ❌              | ✅ HttpClient returns Observable |
+| Event streams           | ❌              | ✅ `fromEvent`, operators        |
+| Complex async flows     | ❌              | ✅ `switchMap`, `mergeMap`       |
+
+---
+
+## 2. Standalone Components
+
+Standalone components are self-contained and don't require NgModule declarations.
+
+### Creating Standalone Components
+
+```typescript
+import { Component } from "@angular/core";
+import { CommonModule } from "@angular/common";
+import { RouterLink } from "@angular/router";
+
+@Component({
+  selector: "app-header",
+  standalone: true,
+  imports: [CommonModule, RouterLink], // Direct imports
+  template: `
+    <header>
+      <a routerLink="/">Home</a>
+      <a routerLink="/about">About</a>
+    </header>
+  `,
+})
+export class HeaderComponent {}
+```
+
+### Bootstrapping Without NgModule
+
+```typescript
+// main.ts
+import { bootstrapApplication } from "@angular/platform-browser";
+import { provideRouter } from "@angular/router";
+import { provideHttpClient } from "@angular/common/http";
+import { AppComponent } from "./app/app.component";
+import { routes } from "./app/app.routes";
+
+bootstrapApplication(AppComponent, {
+  providers: [provideRouter(routes), provideHttpClient()],
+});
+```
+
+### Lazy Loading Standalone Components
+
+```typescript
+// app.routes.ts
+import { Routes } from "@angular/router";
+
+export const routes: Routes = [
+  {
+    path: "dashboard",
+    loadComponent: () =>
+      import("./dashboard/dashboard.component").then(
+        (m) => m.DashboardComponent,
+      ),
+  },
+  {
+    path: "admin",
+    loadChildren: () =>
+      import("./admin/admin.routes").then((m) => m.ADMIN_ROUTES),
+  },
+];
+```
+
+---
+
+## 3. Zoneless Angular
+
+Zoneless applications don't use zone.js, improving performance and debugging.
+
+### Enabling Zoneless Mode
+
+```typescript
+// main.ts
+import { bootstrapApplication } from "@angular/platform-browser";
+import { provideZonelessChangeDetection } from "@angular/core";
+import { AppComponent } from "./app/app.component";
+
+bootstrapApplication(AppComponent, {
+  providers: [provideZonelessChangeDetection()],
+});
+```
+
+### Zoneless Component Patterns
+
+```typescript
+import { Component, signal, ChangeDetectionStrategy } from "@angular/core";
+
+@Component({
+  selector: "app-counter",
+  standalone: true,
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  template: `
+    <div>Count: {{ count() }}</div>
+    <button (click)="increment()">+</button>
+  `,
+})
+export class CounterComponent {
+  count = signal(0);
+
+  increment() {
+    this.count.update((v) => v + 1);
+    // No zone.js needed - Signal triggers change detection
+  }
+}
+```
+
+### Key Zoneless Benefits
+
+- **Performance**: No zone.js patches on async APIs
+- **Debugging**: Clean stack traces without zone wrappers
+- **Bundle size**: Smaller without zone.js (~15KB savings)
+- **Interoperability**: Better with Web Components and micro-frontends
+
+---
+
+## 4. Server-Side Rendering & Hydration
+
+### SSR Setup with Angular CLI
+
+```bash
+ng add @angular/ssr
+```
+
+### Hydration Configuration
+
+```typescript
+// app.config.ts
+import { ApplicationConfig } from "@angular/core";
+import {
+  provideClientHydration,
+  withEventReplay,
+} from "@angular/platform-browser";
+
+export const appConfig: ApplicationConfig = {
+  providers: [provideClientHydration(withEventReplay())],
+};
+```
+
+### Incremental Hydration (v20+)
+
+```typescript
+import { Component } from "@angular/core";
+
+@Component({
+  selector: "app-page",
+  standalone: true,
+  template: `
+    <app-hero />
+
+    @defer (hydrate on viewport) {
+      <app-comments />
+    }
+
+    @defer (hydrate on interaction) {
+      <app-chat-widget />
+    }
+  `,
+})
+export class PageComponent {}
+```
+
+### Hydration Triggers
+
+| Trigger          | When to Use                             |
+| ---------------- | --------------------------------------- |
+| `on idle`        | Low-priority, hydrate when browser idle |
+| `on viewport`    | Hydrate when element enters viewport    |
+| `on interaction` | Hydrate on first user interaction       |
+| `on hover`       | Hydrate when user hovers                |
+| `on timer(ms)`   | Hydrate after specified delay           |
+
+---
+
+## 5. Modern Routing Patterns
+
+### Functional Route Guards
+
+```typescript
+// auth.guard.ts
+import { inject } from "@angular/core";
+import { Router, CanActivateFn } from "@angular/router";
+import { AuthService } from "./auth.service";
+
+export const authGuard: CanActivateFn = (route, state) => {
+  const auth = inject(AuthService);
+  const router = inject(Router);
+
+  if (auth.isAuthenticated()) {
+    return true;
+  }
+
+  return router.createUrlTree(["/login"], {
+    queryParams: { returnUrl: state.url },
+  });
+};
+
+// Usage in routes
+export const routes: Routes = [
+  {
+    path: "dashboard",
+    loadComponent: () => import("./dashboard.component"),
+    canActivate: [authGuard],
+  },
+];
+```
+
+### Route-Level Data Resolvers
+
+```typescript
+import { inject } from '@angular/core';
+import { ResolveFn } from '@angular/router';
+import { UserService } from './user.service';
+import { User } from './user.model';
+
+export const userResolver: ResolveFn<User> = (route) => {
+  const userService = inject(UserService);
+  return userService.getUser(route.paramMap.get('id')!);
+};
+
+// In routes
+{
+  path: 'user/:id',
+  loadComponent: () => import('./user.component'),
+  resolve: { user: userResolver }
+}
+
+// In component
+export class UserComponent {
+  private route = inject(ActivatedRoute);
+  user = toSignal(this.route.data.pipe(map(d => d['user'])));
+}
+```
+
+---
+
+## 6. Dependency Injection Patterns
+
+### Modern inject() Function
+
+```typescript
+import { Component, inject } from '@angular/core';
+import { HttpClient } from '@angular/common/http';
+import { UserService } from './user.service';
+
+@Component({...})
+export class UserComponent {
+  // Modern inject() - no constructor needed
+  private http = inject(HttpClient);
+  private userService = inject(UserService);
+
+  // Works in any injection context
+  users = toSignal(this.userService.getUsers());
+}
+```
+
+### Injection Tokens for Configuration
+
+```typescript
+import { InjectionToken, inject } from "@angular/core";
+
+// Define token
+export const API_BASE_URL = new InjectionToken<string>("API_BASE_URL");
+
+// Provide in config
+bootstrapApplication(AppComponent, {
+  providers: [{ provide: API_BASE_URL, useValue: "https://api.example.com" }],
+});
+
+// Inject in service
+@Injectable({ providedIn: "root" })
+export class ApiService {
+  private baseUrl = inject(API_BASE_URL);
+
+  get(endpoint: string) {
+    return this.http.get(`${this.baseUrl}/${endpoint}`);
+  }
+}
+```
+
+---
+
+## 7. State Management Patterns
+
+### Signal-Based State Service
+
+```typescript
+import { Injectable, signal, computed } from "@angular/core";
+
+interface AppState {
+  user: User | null;
+  theme: "light" | "dark";
+  notifications: Notification[];
+}
+
+@Injectable({ providedIn: "root" })
+export class StateService {
+  // Private writable signals
+  private _user = signal<User | null>(null);
+  private _theme = signal<"light" | "dark">("light");
+  private _notifications = signal<Notification[]>([]);
+
+  // Public read-only computed
+  readonly user = computed(() => this._user());
+  readonly theme = computed(() => this._theme());
+  readonly notifications = computed(() => this._notifications());
+  readonly unreadCount = computed(
+    () => this._notifications().filter((n) => !n.read).length,
+  );
+
+  // Actions
+  setUser(user: User | null) {
+    this._user.set(user);
+  }
+
+  toggleTheme() {
+    this._theme.update((t) => (t === "light" ? "dark" : "light"));
+  }
+
+  addNotification(notification: Notification) {
+    this._notifications.update((n) => [...n, notification]);
+  }
+}
+```
+
+### Component Store Pattern with Signals
+
+```typescript
+import { Injectable, signal, computed, inject } from "@angular/core";
+import { HttpClient } from "@angular/common/http";
+import { toSignal } from "@angular/core/rxjs-interop";
+
+@Injectable()
+export class ProductStore {
+  private http = inject(HttpClient);
+
+  // State
+  private _products = signal<Product[]>([]);
+  private _loading = signal(false);
+  private _filter = signal("");
+
+  // Selectors
+  readonly products = computed(() => this._products());
+  readonly loading = computed(() => this._loading());
+  readonly filteredProducts = computed(() => {
+    const filter = this._filter().toLowerCase();
+    return this._products().filter((p) =>
+      p.name.toLowerCase().includes(filter),
+    );
+  });
+
+  // Actions
+  loadProducts() {
+    this._loading.set(true);
+    this.http.get<Product[]>("/api/products").subscribe({
+      next: (products) => {
+        this._products.set(products);
+        this._loading.set(false);
+      },
+      error: () => this._loading.set(false),
+    });
+  }
+
+  setFilter(filter: string) {
+    this._filter.set(filter);
+  }
+}
+```
+
+---
+
+## 8. Forms with Signals (Coming in v22+)
+
+### Current Reactive Forms
+
+```typescript
+import { Component, inject } from "@angular/core";
+import { FormBuilder, Validators, ReactiveFormsModule } from "@angular/forms";
+
+@Component({
+  selector: "app-user-form",
+  standalone: true,
+  imports: [ReactiveFormsModule],
+  template: `
+    <form [formGroup]="form" (ngSubmit)="onSubmit()">
+      <input formControlName="name" placeholder="Name" />
+      <input formControlName="email" type="email" placeholder="Email" />
+      <button [disabled]="form.invalid">Submit</button>
+    </form>
+  `,
+})
+export class UserFormComponent {
+  private fb = inject(FormBuilder);
+
+  form = this.fb.group({
+    name: ["", Validators.required],
+    email: ["", [Validators.required, Validators.email]],
+  });
+
+  onSubmit() {
+    if (this.form.valid) {
+      console.log(this.form.value);
+    }
+  }
+}
+```
+
+### Signal-Aware Form Patterns (Preview)
+
+```typescript
+// Future Signal Forms API (experimental)
+import { Component, signal } from '@angular/core';
+
+@Component({...})
+export class SignalFormComponent {
+  name = signal('');
+  email = signal('');
+
+  // Computed validation
+  isValid = computed(() =>
+    this.name().length > 0 &&
+    this.email().includes('@')
+  );
+
+  submit() {
+    if (this.isValid()) {
+      console.log({ name: this.name(), email: this.email() });
+    }
+  }
+}
+```
+
+---
+
+## 9. Performance Optimization
+
+### Change Detection Strategies
+
+```typescript
+@Component({
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  // Only checks when:
+  // 1. Input signal/reference changes
+  // 2. Event handler runs
+  // 3. Async pipe emits
+  // 4. Signal value changes
+})
+```
+
+### Defer Blocks for Lazy Loading
+
+```typescript
+@Component({
+  template: `
+    <!-- Immediate loading -->
+    <app-header />
+
+    <!-- Lazy load when visible -->
+    @defer (on viewport) {
+      <app-heavy-chart />
+    } @placeholder {
+      <div class="skeleton" />
+    } @loading (minimum 200ms) {
+      <app-spinner />
+    } @error {
+      <p>Failed to load chart</p>
+    }
+  `
+})
+```
+
+### NgOptimizedImage
+
+```typescript
+import { NgOptimizedImage } from '@angular/common';
+
+@Component({
+  imports: [NgOptimizedImage],
+  template: `
+    <img
+      ngSrc="hero.jpg"
+      width="800"
+      height="600"
+      priority
+    />
+
+    <img
+      ngSrc="thumbnail.jpg"
+      width="200"
+      height="150"
+      loading="lazy"
+      placeholder="blur"
+    />
+  `
+})
+```
+
+---
+
+## 10. Testing Modern Angular
+
+### Testing Signal Components
+
+```typescript
+import { ComponentFixture, TestBed } from "@angular/core/testing";
+import { CounterComponent } from "./counter.component";
+
+describe("CounterComponent", () => {
+  let component: CounterComponent;
+  let fixture: ComponentFixture<CounterComponent>;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      imports: [CounterComponent], // Standalone import
+    }).compileComponents();
+
+    fixture = TestBed.createComponent(CounterComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it("should increment count", () => {
+    expect(component.count()).toBe(0);
+
+    component.increment();
+
+    expect(component.count()).toBe(1);
+  });
+
+  it("should update DOM on signal change", () => {
+    component.count.set(5);
+    fixture.detectChanges();
+
+    const el = fixture.nativeElement.querySelector(".count");
+    expect(el.textContent).toContain("5");
+  });
+});
+```
+
+### Testing with Signal Inputs
+
+```typescript
+import { ComponentFixture, TestBed } from "@angular/core/testing";
+import { ComponentRef } from "@angular/core";
+import { UserCardComponent } from "./user-card.component";
+
+describe("UserCardComponent", () => {
+  let fixture: ComponentFixture<UserCardComponent>;
+  let componentRef: ComponentRef<UserCardComponent>;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      imports: [UserCardComponent],
+    }).compileComponents();
+
+    fixture = TestBed.createComponent(UserCardComponent);
+    componentRef = fixture.componentRef;
+
+    // Set signal inputs via setInput
+    componentRef.setInput("id", "123");
+    componentRef.setInput("name", "John Doe");
+
+    fixture.detectChanges();
+  });
+
+  it("should display user name", () => {
+    const el = fixture.nativeElement.querySelector("h3");
+    expect(el.textContent).toContain("John Doe");
+  });
+});
+```
+
+---
+
+## Best Practices Summary
+
+| Pattern              | ✅ Do                          | ❌ Don't                        |
+| -------------------- | ------------------------------ | ------------------------------- |
+| **State**            | Use Signals for local state    | Overuse RxJS for simple state   |
+| **Components**       | Standalone with direct imports | Bloated SharedModules           |
+| **Change Detection** | OnPush + Signals               | Default CD everywhere           |
+| **Lazy Loading**     | `@defer` and `loadComponent`   | Eager load everything           |
+| **DI**               | `inject()` function            | Constructor injection (verbose) |
+| **Inputs**           | `input()` signal function      | `@Input()` decorator (legacy)   |
+| **Zoneless**         | Enable for new projects        | Force on legacy without testing |
+
+---
+
+## Resources
+
+- [Angular.dev Documentation](https://angular.dev)
+- [Angular Signals Guide](https://angular.dev/guide/signals)
+- [Angular SSR Guide](https://angular.dev/guide/ssr)
+- [Angular Update Guide](https://angular.dev/update-guide)
+- [Angular Blog](https://blog.angular.dev)
+
+---
+
+## Common Troubleshooting
+
+| Issue                          | Solution                                            |
+| ------------------------------ | --------------------------------------------------- |
+| Signal not updating UI         | Ensure `OnPush` + call signal as function `count()` |
+| Hydration mismatch             | Check server/client content consistency             |
+| Circular dependency            | Use `inject()` with `forwardRef`                    |
+| Zoneless not detecting changes | Trigger via signal updates, not mutations           |
+| SSR fetch fails                | Use `TransferState` or `withFetch()`                |