Migrating an Angular CLI project to Nx

Within an Nx workspace, you gain many capabilities that help you build applications and libraries using a monorepo approach. If you are currently using an Angular CLI workspace, you can transform it into an Nx workspace.

Prerequisites

The major version of your Angular CLI must align with the version of Nx you are upgrading to. For example, if you're using Angular CLI version 7, you must transition using the latest version 7 release of Nx.

Using the Nx CLI while preserving the existing structure

To use the Nx CLI in an existing Angular CLI workspace while keeping your existing file structure in place, use the ng add command with the --preserve-angular-cli-layout option:

ng add @nrwl/angular --preserve-angular-cli-layout

Note: If you specify a version of Nx (e.g. ng add @nrwl/angular@13.10.0), please make sure to use the appropriate command as shown in the compatibility table below:

Nx version	Collection to use	Flag to use	Example
>= 13.10.0	`@nrwl/angular`	`--preserve-angular-cli-layout`	`ng add @nrwl/angular@13.10.0 --preserve-angular-cli-layout`
>= 13.8.4 < 13.10.0	`@nrwl/workspace`	`--preserve-angular-cli-layout`	`ng add @nrwl/workspace@13.8.4 --preserve-angular-cli-layout`
< 13.8.4	`@nrwl/workspace`	`--preserveAngularCLILayout`	`ng add @nrwl/workspace@13.5.0 --preserveAngularCLILayout`

This installs the @nrwl/angular (or @nrwl/workspace) package into your workspace and runs a generator (or schematic) to make following changes:

Installs the nx and @nrwl/workspace packages.
Creates an nx.json file in the root of your workspace.
Adds a decorate-angular-cli.js to the root of your workspace, and a postinstall script in your package.json to run the script when your dependencies are updated. The script forwards the ng commands to the Nx CLI (nx) to enable features such as Computation Caching.

After the process completes, you can continue using the same serve/build/lint/test commands you are used to.

Transforming an Angular CLI workspace to an Nx workspace

To fully take advantage of all the features provided by Nx and the Nx Angular plugin, you can do a full migration from an Angular CLI to an Nx workspace.

The automated migration supports Angular CLI workspaces with a standard structure, configurations and features. If your workspace has deviated from what the Angular CLI generates, you might not be able to use the automated migration and you will need to manually migrate your workspace.
Currently, the automated migration supports workspaces using the following executors (builders):
@angular-devkit/build-angular:browser
@angular-devkit/build-angular:dev-server
@angular-devkit/build-angular:extract-i18n
@angular-devkit/build-angular:karma
@angular-devkit/build-angular:ng-packagr
@angular-devkit/build-angular:protractor
@angular-devkit/build-angular:server
@angular-eslint/builder:lint
@cypress/schematic:cypress
@nguniversal/builders:prerender
@nguniversal/builders:ssr-dev-server
Support for other executors may be added in the future.

To transform an Angular CLI workspace to an Nx workspace, run the following command:

ng add @nrwl/angular

Note: If you specify a version of Nx (e.g. ng add @nrwl/angular@13.10.0), please make sure to use the appropriate command as shown in the compatibility table below:

Nx version	Command to run
>= 13.10.0	`ng add @nrwl/angular`
< 13.10.0	`ng add @nrwl/workspace`

Note: Support for workspaces with multiple applications and libraries was added in Nx v14.1.0. If you are migrating using an older version of Nx, your workspace can only contain one application and no libraries in order to use the automated migration, otherwise, you can still migrate manually.

This installs the @nrwl/angular (or @nrwl/workspace) package into your workspace and runs a generator (or schematic) to transform your workspace. The generator applies the following changes to your workspace:

Installs the nx and @nrwl/workspace packages.
Creates an nx.json file in the root of your workspace.
Creates configuration files for Prettier.
Creates an apps folder for generating applications.
Creates a libs folder for generating libraries.
Creates a tools folder that includes files for custom workspace tooling, such as workspace-specific generators and scripts.
Moves your applications into the apps folder, and updates the relevant file paths in your configuration files.
Moves your e2e suites into the apps/<app name>-e2e folder, and updates the relevant file paths in your configuration files.
Moves your libraries into the libs folder, and updates the relevant file paths in your configuration files.
Updates your package.json scripts to use nx instead of ng.
Splits your angular.json into project.json files for each project with updated paths.
Updates the angular.json configuration to reflect the changes made.

After the changes are applied, your workspace file structure should look similar to the one below:

<workspace name>/
├── apps/
│   ├── <app name>/
│   │   ├── src/
│   │   │   ├── app/
│   │   │   ├── assets/
│   │   │   ├── environments/
│   │   │   ├── favicon.ico
│   │   │   ├── index.html
│   │   │   ├── main.ts
│   │   │   ├── polyfills.ts
│   │   │   ├── styles.css
│   │   │   └── test.ts
│   │   ├── .browserslistrc
│   │   ├── karma.conf.js
│   │   ├── project.json
│   │   ├── tsconfig.app.json
│   │   └── tsconfig.spec.json
│   └── <app name>-e2e/
│       ├── src/
│       ├── protractor.conf.js | cypress.json
│       ├── project.json
│       └── tsconfig.json
├── libs/
│   └── <lib name>/
│       ├── src/
│       ├── .browserslistrc
│       ├── karma.conf.js
│       ├── ng-package.json
│       ├── package.json
│       ├── project.json
│       ├── README.md
│       ├── tsconfig.lib.json
│       ├── tsconfig.lib.prod.json
│       └── tsconfig.spec.json
├── tools/
├── .editorconfig
├── .gitignore
├── .prettierignore
├── .prettierrc
├── angular.json
├── decorate-angular-cli.js
├── karma.conf.js
├── nx.json
├── package.json
├── README.md
└── tsconfig.base.json

Your workspace is now powered by Nx! You can verify out that your application still runs as intended:

To serve, run ng serve (or nx serve).
To build, run ng build (or nx build).
To run unit tests, run ng test (or nx test).
To run e2e tests, run ng e2e (or nx e2e).
To see your project graph, run nx graph.

Your project graph will grow as you add, and use more applications and libraries. You can add the --watch flag to nx graph to see this changes in-browser as you add them.

Learn more about the advantages of Nx in the following guides:

Migrating multiple Angular CLI workspaces into an Nx Monorepo

Migrating multiple Angular CLI workspaces into a single Nx monorepo involves some more manual steps and decisions to take.

can we first align all apps to the same Angular version (e.g. using Angular CLI migrations)
convert each of the apps into an easy to copy "Nx shape" (with project.json etc) using some of the before mentioned migration scripts
copy everything into a new Nx workspace

Very often however we might also need to do it incrementally, such as

migrating all apps into a monorepo
keep them at different Angular & external dependency versions until everything is migrated
migrate them one by one incrementally and over time

The following video tutorial walks you through such a scenario.

Migrating an Angular app manually

If you are unable to automatically transform your Angular CLI workspace to an Nx workspace using the ng add method, there are some manual steps you can take to move your project(s) into an Nx workspace.

Generating a new workspace

To start, run the command to generate an Nx workspace with an Angular application.

Using npx

npx create-nx-workspace myorg --preset=angular

Using npm init

npm init nx-workspace myorg --preset=angular

Using yarn create

yarn create nx-workspace myorg --preset=angular

When prompted for the application name, enter the project name from your current angular.json file.

A new Nx workspace with your org name as the folder name, and your application name as the first application is generated.

<workspace name>/
├── apps/
│   ├── <app name>/
│   │   ├── src/
│   │   │   ├── app/
│   │   │   ├── assets/
│   │   │   ├── environments/
│   │   │   ├── favicon.ico
│   │   │   ├── index.html
│   │   │   ├── main.ts
│   │   │   ├── polyfills.ts
│   │   │   ├── styles.css
│   │   │   └── test.ts
│   │   ├── browserslist
│   │   ├── jest.conf.js
│   │   ├── tsconfig.app.json
│   │   ├── tsconfig.json
│   │   ├── tslint.json
│   │   └── tsconfig.spec.json
│   └── <app name>-e2e/
│       ├── src/
│       ├── cypress.json
│       ├── tsconfig.e2e.json
│       ├── tslint.json
│       └── tsconfig.json
├── libs/
├── tools/
├── .editorconfig
├── .eslintrc.json
├── .gitignore
├── .prettierignore
├── .prettierrc
├── angular.json
├── decorate-angular-cli.js
├── jest.config.js
├── jest.preset.js
├── nx.json
├── package.json
├── README.md
└── tsconfig.base.json

Copying over application files

Your application code is self-contained within the src folder of your Angular CLI workspace.

Copy the src folder from your Angular CLI project to the apps/<app name> folder, overwriting the existing src folder.
Copy any project-specific configuration files, such as browserslist, or service worker configuration files into their relative path under the apps/<app name> folder.
Transfer the assets, scripts, styles, and build-specific configuration, such as service worker configuration, from your Angular CLI angular.json to the apps/<app name>/project.json file.

Verify your application runs correctly by running:

ng serve <app name>

Updating your unit testing configuration

Nx uses Jest by default. If you have any custom Jest configuration, you need to update the workspace Jest configuration also.

Verify your tests run correctly by running:

ng test <app name>

If you are using Karma for unit testing:

Copy the karma.conf.js file to your apps/<app name> folder.
Copy the test.ts file to your apps/<app name>/src folder.
Copy the test target in your architect configuration from your Angular CLI angular.json file into the targets configuration in the apps/<app name>/project.json file in your Nx workspace.
Update the test target file paths to be relative to apps/<app name>.

1// apps/<app name>/project.json
2{
3  "projectType": "application",
4  "sourceRoot": "apps/<app name>/src",
5  "prefix": "myapp",
6  "targets": {
7    "test": {
8      "executor": "@angular-devkit/build-angular:karma",
9      "options": {
10        "main": "apps/<app name>/src/test.ts",
11        "polyfills": "apps/<app name>/src/polyfills.ts",
12        "tsConfig": "apps/<app name>/tsconfig.spec.json",
13        "karmaConfig": "apps/<app name>/karma.conf.js",
14        "assets": [
15          "apps/<app name>/src/favicon.ico",
16          "apps/<app name>/src/assets"
17        ],
18        "styles": ["apps/<app name>/src/styles.css"],
19        "scripts": []
20      }
21    }
22    ...
23  }
24}
25

Jest will be used by default when generating new applications. If you want to continue using Karma, set the unitTestRunner to karma in the generators section of the nx.json file.

Update test-setup.ts to test.ts in the files array of the apps/<app name>/tsconfig.spec.json file.

1{
2  "extends": "./tsconfig.json",
3  "compilerOptions": {
4    "outDir": "../../dist/out-tsc",
5    "types": ["jasmine", "node"]
6  },
7  "files": ["src/test.ts", "src/polyfills.ts"],
8  "include": ["**/*.spec.ts", "**/*.test.ts", "**/*.d.ts"]
9}
10

Verify your tests run correctly by running:

ng test <app name>

Updating your E2E testing configuration

Nx uses Cypress by default. If you are already using Cypress, copy your E2E setup files into the apps/<app name>-e2e folder and verify your tests still run correctly by running:

ng e2e <app name>-e2e

If you are using Protractor for E2E testing:

Delete the apps/<app name>-e2e folder that was generated to use Cypress.
Copy the e2e folder from your Angular CLI workspace into the apps folder.
Rename the e2e folder to <app name>-e2e.
Create the project configuration file at apps/<app name>-e2e/project.json.
Copy the project configuration for app name from the Angular CLI workspace angular.json file to apps/<app name>-e2e/project.json and adjust the file paths to be relative to apps/<app name>-e2e.

1// apps/<app name>-e2e/project.json
2{
3  "projectType": "application",
4  "targets": {
5    "e2e": {
6      "executor": "@angular-devkit/build-angular:protractor",
7      "options": {
8        "protractorConfig": "apps/<app name>-e2e/protractor.conf.js"
9      },
10      "configurations": {
11        "production": {
12          "devServerTarget": "<app name>:serve:production"
13        },
14        "development": {
15          "devServerTarget": "<app name>:serve:development"
16        }
17      }
18      "defaultConfiguration": "development"
19    },
20    "lint": {
21      "executor": "@angular-devkit/build-angular:tslint",
22      "options": {
23        "tsConfig": "apps/<app name>-e2e/tsconfig.e2e.json",
24        "exclude": ["**/node_modules/**", "!apps/<app name>-e2e/**/*"]
25      }
26    }
27  },
28  "implicitDependencies": ["<app name>"],
29  "tags": []
30}
31

Create a tsconfig.e2e.json file under apps/<app name>-e2e folder:

1{
2  "extends": "./tsconfig.json",
3  "compilerOptions": {
4    "outDir": "../../dist/out-tsc"
5  }
6}
7

Update the apps/<app name>/tsconfig.json to extend the root tsconfig.json:

1{
2  "extends": "../../tsconfig.json",
3  "compilerOptions": {
4    "outDir": "../../out-tsc/<app name>-e2e",
5    "module": "commonjs",
6    "target": "es5",
7    "types": ["jasmine", "jasminewd2", "node"]
8  }
9}
10

Verify your E2E tests run correctly by running:

ng e2e <app name>-e2e

Cypress will be used by default when generating new applications. If you want to continue using Protractor, set the e2eTestRunner to protractor in the generators section of the nx.json file.

Updating your linting configuration

For lint rules, migrate your existing rules into the root tslint.json file.

Verify your lint checks run correctly by running:

npm run lint

yarn lint

Learn more about the advantages of Nx in the following guides:

Using Cypress for e2e tests
Using Jest for unit tests
Rebuilding and Retesting What is Affected

From Nx Console

As of Nx Console version 17.15.0, Angular CLI users will receive a notice periodically when running commands via Nx Console, asking if they want to use Nx to make their Angular commands faster.

When you click this button, we’ll run the make-angular-cli-faster script to decorate your Angular workspace with Nx, allowing for cached builds, and for you to share this cache with your teammates via Nx Cloud.

The script will make the following changes:

Installs the @nrwl/workspace and nx packages.
- If you opted into Nx Cloud, @nrwl/nx-cloud will be installed as well.
- If your project's Angular version is greater than or equal to version 13, then the @nrwl/angular package will be installed as well.
Creates an nx.json file in the root of your workspace.
Adds a decorate-angular-cli.js to the root of your workspace, and a postinstall script in your package.json to run the script when your dependencies are updated. The script forwards the ng commands to the Nx CLI (nx) to enable features such as Computation Caching.

By running this command and accepting Nx Cloud, Nx distributed caching is now enabled.

Once the script has run, commit the changes. Reverting these changes will effectively undo the changes made.

If you're not ready to make the change yet, you can come back to this later:

If you're using Nx Console: open the Vs Code command palette and start typing "make angular faster".
Regardless of using Nx Console (or your IDE): run npx make-angular-cli-faster from the root of your project.