Signal-based architecture for your Angular apps | Alain Chautard

Signals provide more precise change detection in Angular by only updating components that depend on changed values, rather than checking the entire component tree

Key benefits include:

• Simpler alternative to RxJS for reactivity
• Lightweight (2KB) and built into Angular
• Automatic dependency tracking
• Better debugging via Angular DevTools
• Improved performance through focused updates

Best practices for using signals:

• Convert template-bound values to signals
• Use computed() for derived values
• Make signals required and provide initial values when possible
• Expose signals as read-only when appropriate
• Use input() function instead of @Input() decorator

Signal-based architecture recommendations:

• Migrate existing inputs to signal inputs
• Keep components focused and reusable
• Use services to manage shared state
• Convert observables to signals when possible
• Think in terms of dependencies and transformations

Signal API key concepts:

• signal() creates a basic signal
• computed() derives values from other signals
• toSignal() converts observables to signals
• .set() updates signal values directly
• .update() modifies based on previous value

Signals represent Angular’s future direction for state management and change detection, preparing applications for upcoming framework changes

Migration can be gradual - existing applications can mix traditional change detection with signal-based approaches

TypeScript integration provides better type safety and developer experience when working with signals