angular-developer

Run ng new <project-name> if the Angular CLI is installed locally, or npx @angular/cli@latest new <project-name> to fetch the latest version. To target a specific version, use npx @angular/cli@<version> new <project-name>.

Use signal() for writable state, computed() for strictly derived values, and linkedSignal() when derived state must remain user-editable. Avoid using effect() to sync state between signals, as that causes change detection errors.

For new forms in Angular v21 or newer, prefer signal forms. For older applications or existing form implementations, match the project's current strategy using reactive forms for complex cases or template-driven forms for simple ones.

Yes, use loadComponent to lazy-load a single component or loadChildren to lazy-load a route subtree. Loader functions run in an injection context, so you can call inject() for context-aware loading decisions.

Calling .set() or .update() on a signal inside an effect causes ExpressionChangedAfterItHasBeenChecked errors and potential infinite loops. Use computed() or linkedSignal() for state derivation, reserving effects for logging, storage sync, or third-party DOM integration.

Use TestbedHarnessEnvironment.loader(fixture) to get a HarnessLoader, then load harnesses like MatButtonHarness.with({ text: 'Submit' }). Harness APIs handle async waiting and change detection, making tests resilient to DOM refactoring.