Angular 18 to 19 Upgrade Guide

✅ Before You Start: Backup First

Important: Always take a full backup of your project or commit all changes to version control before upgrading.

🔧 Step-by-Step Upgrade Instructions

1. Update Angular CLI and Core Packages

ng update @angular/core@19 @angular/cli@19

2. Update Angular Material (If used)

ng update @angular/material@19

3. Optional: Update Other Dependencies

npm outdated
npm install rxjs@latest zone.js@latest

4. Clean and Reinstall Packages

rm -rf node_modules package-lock.json
npm install

5. Update TypeScript Version

npm install typescript@latest

⚠️ Common Issues & Fixes

SSR Packager / `itconfig.app.json` Errors

If you're not using SSR and encounter errors, remove SSR-related configurations in angular.json under configurations.ssr.

💬 Reviewer Comment Example


Upgraded Angular version from 18 to 19 to ensure compatibility with latest features, performance improvements, and security patches.
Please verify UI/UX and test critical flows after the upgrade.
No functional code changes were made during this update.

📈 ChangeLog

Updated @angular/core and @angular/cli to v19
Updated supporting packages: RxJS, Zone.js, TypeScript
Removed deprecated SSR config causing build issues
Cleaned node_modules and lock file

📌 Key Technologies & Features in Angular 19

Improved build speed via Vite & ESBuild
Incremental hydration for SSR
Better debugging tools
Updated Angular Material UI components

🛠 How to Upgrade from Angular 18 to 19 (Quick Recap)

ng update @angular/core@19 @angular/cli@19

After upgrading, test your app thoroughly and review the official changelog for breaking changes.