---
title: Angular Migration
category: product
entity_type: skill
price: $15
canonical: https://forgehouse.ai/skills/angular-migration/
lang: en
hreflang_alt: https://forgehouse.ai/tr/skiller/angular-migration/
last_updated: 2026-06-20
---

# Angular Migration

> Migrate from AngularJS to Angular using hybrid mode, incremental component rewriting, and…

A complete migration playbook for moving AngularJS (1.x) applications to modern Angular without a risky big-bang rewrite. It uses the Strangler Fig and hybrid-app approach so old and new run side by side, letting you migrate one feature at a time while production stays stable. Every conversion: controllers, directives, services, routing, and forms, comes with before/after code.

## Use cases
- Migrating a large legacy AngularJS app to Angular feature by feature
- Running a hybrid AngularJS/Angular app with ngUpgrade interop
- Converting AngularJS controllers and directives to Angular components
- Modernizing factory services into injectable Angular services with RxJS
- Replacing $routeProvider routing with the Angular Router
- Moving ng-model forms to reactive forms with validation

## Benefits
- Zero downtime: you migrate incrementally instead of freezing the product
- Reversible at any point, so a bad sprint never blocks production
- A predictable timeline broken into setup, infrastructure, feature, and cleanup phases
- A modern, type-safe codebase free of legacy $scope patterns

## What’s included
- Three migration strategies (big bang, incremental hybrid, vertical slice) with fit criteria
- Hybrid app bootstrap setup with UpgradeModule and strictDi
- Bidirectional dependency injection bridges (downgradeInjectable / InjectionToken)
- Worked controller, directive, service, routing, and form conversions
- A phased migration timeline template for project planning
- Common-pitfall checklist covering change detection and scope handling

## Who it’s for
Frontend engineers and tech leads responsible for modernizing a legacy AngularJS application without disrupting users.

## How it runs
Rewrites kill AngularJS apps; strangler-fig migrations retire them. Both frameworks run side by side from day one, and features cross over one vertical slice at a time:
1. Analyzes the legacy app first: every controller, directive, service and route is inventoried, then a strategy is picked from the matrix: hybrid for large apps, vertical slice for medium, big bang only for small ones.
2. Bootstraps the hybrid shell: AngularJS stays the root app, UpgradeModule boots Angular next to it in main.ts, so both frameworks run in the same page from day one and the migration can pause at any point with production still stable.
3. Migrates services before UI: factories become @Injectable classes, with downgradeInjectable and InjectionToken bridges so both sides can call either implementation during the transition without breaking consumers.
4. Converts one feature per sprint as a vertical slice: controller to component, directive scope bindings to Input/Output, and that feature's routing and forms move together, so every sprint ends with a fully-Angular feature.
5. Guards the boundary as an anti-corruption layer: no $scope.$watch or $apply leaks into Angular components, digest-cycle vs zone.js change detection differences stay isolated in the upgrade layer.
6. Cleanup phase closes it: ngUpgrade and all AngularJS dependencies are removed, routing switches fully to Angular Router, the bundle gets optimized and a final regression pass confirms nothing old-side broke.

## FAQ
### Can the app stay live for users while we migrate?
Yes, that is the point of the feature-by-feature approach over a big-bang rewrite. ngUpgrade runs AngularJS and Angular side by side so users keep working through the transition.

### Running both frameworks at once must bloat the bundle; is the hybrid phase actually worth it?
The hybrid phase does carry both runtimes temporarily, which is the trade for not freezing the product during a rewrite. It is a transitional state you exit feature by feature, not the end configuration.

### Does this cover upgrading from a newer Angular version too?
No, it is specifically AngularJS 1.x to modern Angular, which is a framework rewrite, not a version bump. Moving between modern Angular releases is a different kind of upgrade.

## Price
$15, one-time, no subscription. VAT included.

Related guide: [AI code review and developer workflow](https://forgehouse.ai/guides/ai-code-review/)