ng build compiles the application into an output directory

ng build

The build artifacts will be stored in the dist/ directory.

All commands that build or serve your project, ng build/serve/e2e, will delete the output directory (dist/ by default). This can be disabled via the --no-delete-output-path (or --delete-output-path=false) flag.

ng build can specify both a build target (--target=production or --target=development) and an environment file to be used with that build (--environment=dev or --environment=prod). By default, the development build target and environment are used.

The mapping used to determine which environment file is used can be found in .angular-cli.json:

"environmentSource": "environments/environment.ts",
"environments": {
  "dev": "environments/environment.ts",
  "prod": "environments/environment.prod.ts"
}

These options also apply to the serve command. If you do not pass a value for environment, it will default to dev for development and prod for production.

# these are equivalent
ng build --target=production --environment=prod
ng build --prod --env=prod
ng build --prod
# and so are these
ng build --target=development --environment=dev
ng build --dev --e=dev
ng build --dev
ng build

You can also add your own env files other than dev and prod by doing the following:

• create a src/environments/environment.NAME.ts
• add { "NAME": 'src/environments/environment.NAME.ts' } to the apps[0].environments object in .angular-cli.json
• use them via the --env=NAME flag on the build/serve commands.

When building you can modify base tag (<base href="https://github.com/">) in your index.html with --base-href your-url option.

# Sets base tag href to /myUrl/ in your index.html
ng build --base-href /myUrl/
ng build --bh /myUrl/

All builds make use of bundling and limited tree-shaking, while --prod builds also run limited dead code elimination via UglifyJS.

Both --dev/--target=development and --prod/--target=production are 'meta' flags, that set other flags. If you do not specify either you will get the --dev defaults.

--extract-licenses Extract all licenses in a separate file, in the case of production builds only. --i18n-file Localization file to use for i18n. --prod also sets the following non-flaggable settings:

• Adds service worker if configured in .angular-cli.json.
• Replaces process.env.NODE_ENV in modules with the production value (this is needed for some libraries, like react).
• Runs UglifyJS on the code.

Resources in CSS, such as images and fonts, will be copied over automatically as part of a build. If a resource is less than 10kb it will also be inlined.

You'll see these resources be outputted and fingerprinted at the root of dist/.

There is experimental service worker support for production builds available in the CLI. To enable it, run the following commands:

npm install @angular/service-worker --save
ng set apps.0.serviceWorker=true

On --prod builds a service worker manifest will be created and loaded automatically. Remember to disable the service worker while developing to avoid stale code.

Note: service worker support is experimental and subject to change.