Using the Angular Update Guide

The Angular Update Guide is an interactive web tool that provides tailored instructions for updating your Angular application.
This section explains how to use it effectively with Angular 21.

How to Navigate the Guide

1. Select your current version and the target version you want to reach (e.g., from 19.0 to 21.0).
2. Choose the complexity of your application:
   • Basic – simple apps with few dependencies.
   • Medium – typical business applications.
   • Advanced – large enterprise apps with custom configurations.
3. Review the generated checklist. It includes:
   • Required ng update commands.
   • Manual steps (e.g., updating third‑party libraries, modifying configuration).
   • Links to detailed migration guides for specific features.

Example Checklist for v19 → v21

Step	Action
1	Update Angular CLI to the latest v20: ng update @angular/cli@20
2	Update Angular core to v20: ng update @angular/core@20
3	Migrate to standalone components (if not already): ng generate @angular/core:standalone
4	Update Angular CLI to v21: ng update @angular/cli@21
5	Update Angular core to v21: ng update @angular/core@21
6	Manually update other dependencies (e.g., RxJS, TypeScript) as suggested.

Important Tips

• Always run ng update one major version at a time – skipping versions increases the risk of conflicts.
• After each ng update, run your tests (ng test) and build the application (ng build) to verify everything works.
• The guide also provides recommended next steps like adopting new features (signals, control flow) after the update.

Integrating with Angular 21 Features

Once you have updated to v21, the guide may suggest further optional migrations:

• New control flow syntax: ng generate @angular/core:control-flow
• Signal inputs: ng generate @angular/core:signals
• Remove deprecated @Injectable() providers: ng generate @angular/core:injectable

These help you leverage the latest performance and developer experience improvements.