Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
Authentication State in Angular: Functional Guards, Interceptors, Single-Flight Token Refresh and UI Authorization
Guards and hidden buttons in Angular are user experience, not a security boundary; the real decision is made in the API. We write a signal-based auth state service, canMatch guards, a permission directive, an interceptor that ties concurrent 401s to a single refresh, and cross-tab sign-out with BroadcastChannel, test them all with Vitest, and show that a request bypassing the guard gets a 403 from the API.
Unidirectional Data Flow in Angular: Signals, input/output and State in Services
Unidirectional data flow in Angular means the state has a single owner, data goes down with input(), change requests go up with output(), and derived values are computed with computed(). With real tests we show how state written by an effect lags behind, how model() bypasses a business rule and why default OnPush misses an array changed in place, then move the state into a service that holds signals.
Angular 20: Stable Signal APIs, httpResource and the New File Naming
In Angular 20, effect, toSignal and linkedSignal become stable, resource swaps request for params, httpResource arrives, app.ts replaces app.component.ts and *ngIf gets deprecated.
Angular 19: Standalone by Default, linkedSignal and Data Loading with resource()
In Angular 19 you no longer write standalone: true. We compare linkedSignal for dependent state and the experimental resource() and rxResource for data loading with the Angular 12 way.
What's New in Angular 18: Zoneless Change Detection, @let and Stable Control Flow
Experimental zoneless change detection in Angular 18, control flow and @defer going stable, @let from 18.1, ng-content fallback content, unified form events and redirect functions.
What's New in Angular 17.x: input(), model(), output() and Signal Queries
input(), input.required(), model(), output() and the viewChild()/viewChildren() signal queries from Angular 17.1–17.3, side by side with their Angular 12 @Input, @Output and @ViewChild counterparts.
What's New in Angular 16: Signals, Required Inputs and takeUntilDestroyed
Signals, computed and effect, the toSignal/toObservable bridge, required inputs and transforms, and subscription cleanup with takeUntilDestroyed in Angular 16, compared with Angular 12.