Q: Signal inputs input() vs @Input() — what changes in Angular 17.1+?

**Target Audience:** Developers who know classic @Input() and want to understand the signal version — assumes basic components and templates. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every output, compiler error and generated line below came from compiling the code with ngc (strict templates) on Angular 22.2.3 and running it in jsdom, or from running the Angular CLI 22.2.3 migration schemati

Q: output() vs @Output() EventEmitter — the new signal outputs?

**Target Audience:** Developers who know @Output() and EventEmitter — assumes the basics of [child-to-parent events](/interview-question/how-do-child-components-emit-events-to-parents). **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. The basics of emitting an event are covered in [how child components emit events to parents](/interview-question/how-do-child-components-emit-events-to-parents); this

Q: Deferrable views — prefetch strategies and dependency isolation with @defer?

**Target Audience:** Developers who already use @defer and want to know what the compiler does with it, and how to control when code is downloaded. **Difficulty:** Hard > **How to read this doc:** Ideas are explained in plain language first, then tagged with 📌 Interview term: so you also learn the words an interviewer listens for. The compiled code in sections 3 and 4 is real ngc output (see [how Ivy compilation works](/interview-question/how-does-compila

Question 1

Standalone bootstrapApplication — how does Angular bootstrap without NgModules in 2025?

Accepted Answer

**Target Audience:** Developers who can bootstrap an app and now want to explain what happens underneath, for senior interviews or for debugging startup problems. **Difficulty:** Medium to Hard > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. The sequence below was read from the installed Angular 22.2.3 source (bootstrapApplication in @angular/platform-browser, internalCreateApplication and bootstrap

Question 2

Signal inputs input() vs @Input() — what changes in Angular 17.1+?

Accepted Answer

**Target Audience:** Developers who know classic @Input() and want to understand the signal version — assumes basic components and templates. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. Every output, compiler error and generated line below came from compiling the code with ngc (strict templates) on Angular 22.2.3 and running it in jsdom, or from running the Angular CLI 22.2.3 migration schemati

Question 3

output() vs @Output() EventEmitter — the new signal outputs?

Accepted Answer

**Target Audience:** Developers who know @Output() and EventEmitter — assumes the basics of [child-to-parent events](/interview-question/how-do-child-components-emit-events-to-parents). **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts. The basics of emitting an event are covered in [how child components emit events to parents](/interview-question/how-do-child-components-emit-events-to-parents); this

Question 4

How does the new control flow @if / @for / @switch replace *ngIf and *ngFor?

Accepted Answer

**Target Audience:** Developers maintaining an Angular codebase that still uses *ngIf, *ngFor and ngSwitch, and anyone asked "how would you migrate this?" in an interview. **Difficulty:** Medium > **How to read this doc:** Plain language first, then 📌 Interview term: callouts with the vocabulary an interviewer expects. Everything quoted below was produced on Angular 22.2.3: both examples were AOT-compiled with strict templates and run in jsdo

Question 5

Deferrable views — prefetch strategies and dependency isolation with @defer?

Accepted Answer

**Target Audience:** Developers who already use @defer and want to know what the compiler does with it, and how to control when code is downloaded. **Difficulty:** Hard > **How to read this doc:** Ideas are explained in plain language first, then tagged with 📌 Interview term: so you also learn the words an interviewer listens for. The compiled code in sections 3 and 4 is real ngc output (see [how Ivy compilation works](/interview-question/how-does-compila

ANGULARDECODED.

Medium

Standalone bootstrapApplication — how does Angular bootstrap without NgModules in 2025?

Signal inputs input() vs @Input() — what changes in Angular 17.1+?

output() vs @Output() EventEmitter — the new signal outputs?

How does the new control flow @if / @for / @switch replace ngIf and ngFor?

Hard

Deferrable views — prefetch strategies and dependency isolation with @defer?