Angular 21: Most Popular New Features

Angular 21 represents a significant milestone in the framework's evolution, bringing powerful new features that enhance developer experience, improve performance, and modernize the development workflow. This release continues Angular's commitment to staying at the forefront of web development technology.

1 Incremental Hydration NEW

One of the most anticipated features in Angular 21 is incremental hydration, which allows developers to hydrate components progressively rather than all at once. This significantly improves the initial page load performance and Time to Interactive (TTI) metrics for server-side rendered applications.

import { Component } from '@angular/core';

// Enable incremental hydration for this component
@Component({
  selector: 'app-product-list',
  template: `...`,
  hydration: { 
    strategy: 'incremental',
    priority: 'high'
  }
})
export class ProductListComponent { }
                

Key Benefits:

Faster initial page loads with progressive component hydration
Better user experience with prioritized interactive elements
Reduced JavaScript execution time during page initialization
Fine-grained control over hydration strategy per component

2 Enhanced Signals API

Angular 21 builds upon the Signals foundation with enhanced APIs that make reactive programming more intuitive and powerful. The new linkedSignal() and improved computed signals provide better composition patterns.

import { signal, computed, linkedSignal } from '@angular/core';

// Create linked signals with automatic updates
const count = signal(0);
const doubled = linkedSignal(() => count() * 2);

// Enhanced computed with dependencies tracking
const displayText = computed(() => {
  return `Count: ${count()}, Doubled: ${doubled()}`;
});
                

Key Benefits:

More expressive reactive patterns with linkedSignal()
Better performance with optimized change detection
Simplified state management without external libraries
Improved TypeScript inference for signal values

3 Built-in Control Flow Improvements

The template syntax for control flow continues to evolve with new enhancements to @if, @for, and @switch directives. Angular 21 adds better performance optimizations and new convenience features.

<!-- Enhanced @for with track optimization -->
@for (item of items; track item.id; let idx = $index) {
  <div>{{ idx + 1 }}. {{ item.name }}</div>
} @empty {
  <p>No items available</p>
}

<!-- Improved @if with else if chains -->
@if (status === 'loading') {
  <app-spinner />
} @else if (status === 'error') {
  <app-error-message />
} @else {
  <app-content />
}
                

Key Benefits:

More readable template syntax compared to structural directives
Better performance with optimized change tracking
Reduced bundle size by removing legacy directive code
Enhanced developer experience with better IDE support

4 TypeScript 5.7 Support

Angular 21 fully embraces TypeScript 5.7, bringing the latest language features and type system improvements to Angular developers. This includes better type inference, improved error messages, and new utility types.

// Leveraging TypeScript 5.7 features
type User = {
  id: number;
  name: string;
  email?: string;
};

// Improved type inference in Angular services
@Injectable({ providedIn: 'root' })
export class UserService {
  getUser(id: number): Observable<User> {
    return this.http.get<User>(`/api/users/${id}`);
  }
}
                

Key Benefits:

Enhanced type safety with improved inference
Better developer experience with clearer error messages
Access to latest TypeScript features and optimizations
Improved compile-time performance

5 Material 3 Integration PREVIEW

Angular 21 includes preview support for Material Design 3 (Material You), bringing modern design principles and theming capabilities to Angular Material components. This represents a significant visual and functional upgrade.

import { provideAnimations } from '@angular/platform-browser/animations';
import { provideMaterial3 } from '@angular/material';

// Configure Material 3 theme
export const appConfig = {
  providers: [
    provideAnimations(),
    provideMaterial3({
      theme: 'dynamic',
      colorScheme: 'auto'
    })
  ]
};
                

Key Benefits:

Modern, adaptive design system with dynamic theming
Improved accessibility features across all components
Better color contrast and readability
Seamless dark mode support with system preferences

6 Developer Experience Enhancements

Angular 21 includes numerous quality-of-life improvements for developers, including better error messages, improved CLI diagnostics, faster builds, and enhanced debugging capabilities.

Notable Improvements:

Faster compilation with optimized Angular compiler
More helpful error messages with actionable suggestions
Enhanced source maps for better debugging experience
Improved hot module replacement for faster development cycles
Better tree-shaking resulting in smaller bundle sizes