All 5 Zoneless Change Detection & Zone.js questions
More in Zoneless Change Detection & Zone.js
What is Zone.js, and what role does it traditionally play in Angular applications? Why is Angular investing in zoneless change detection as the future direction for the framework? What does zoneless change detection mean, and how does Angular know when to update the screen without Zone.js? How would you migrate an existing Zone.js based Angular application toward zoneless change detection safely?
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Angular › Zoneless Change Detection & Zone.js

What are the main benefits of removing Zone.js from an Angular application?

Intermediate

Answer

Removing Zone.js reduces the amount of JavaScript the browser needs to download and parse, avoids the overhead of patching many browser APIs, and generally leads to faster startup and runtime performance, since Angular can rely on precise signals instead of checking the whole application on every possible event.
// Bundle size and performance improve because Angular
// no longer needs to patch setTimeout, Promise, addEventListener,
// and dozens of other browser APIs at startup
Real-world example A mobile focused web app removes Zone.js to shrink its bundle size and improve startup time on slower phones, giving users a noticeably faster first experience when opening the app.

Common follow-ups: How much smaller does a typical bundle become after removing Zone.js?;Are there any compatibility issues with third party libraries after removing Zone.js?

Performance & Lazy Loading;Angular CLI & Project Structure
All 5 Zoneless Change Detection & Zone.js questions