Core libraries, configuration and tools
Last modified on Mon 04 Jan 2021

Angular CLI

The best way to create a new project is by using Angular CLI. It will hide a lot of configuration behind the scenes (you will not have a Webpack config exposed for editing), do some optimizations when compiling your code, and offer some handy scaffolding tools.

Install Angular CLI globally with npm install -g @angular/cli and check out what you can do with ng help.

Creating a new project

Use Angular CLI for the initial project setup:

ng new my-app --strict

As of version 7, there will be a quick wizard-like setup advising you about routing and styling. Choose depending on your needs. All of our Angular projects here at Infinum use routing and SCSS styling.

We recommend using the --strict flag when creating a new project, as it enables some additional TypeScript and Angular template checks.


You can use Angular CLI to generate new modules, components, services, directives, etc.

The command is ng generate [schematic-name], for example, ng generate component. There is also a shorthand for many generation commands, for example, ng g c === ng generate component. Run ng generate --help to see a list of all available options and schematics.

There are also some 3rd party schematics you can use or you can even create your own schematics, but that is out of the scope of this handbook.

Creating new modules

Use ng g m MyModule to create a new module. If the module should have routes, you can generate a module with a routing skeleton with ng g m MyModule --routing.

Creating new components

Create components with ng g c MyComponent or ng g c my-component. In both cases, the resulting component class name will be MyComponent, and the directory name will be my-component.

Usually, you want to create a component module when creating components. This makes the component more modular and ensures that everything that the component needs is provided by the component module. The component module should declare and export the component—you can think of it as a public API. The component module could also declare some other "internal" components, but it does not have to necessarily export those internal components. It is our recommendation that component modules export only one declared component.

Having a module for each component makes managing component dependencies a lot easier.

Also remember that a component can be declared only once (in one module), so it makes sense for reusable components to have their own module.


# create a module
ng g m Calendar

# create the component - this will also automatically declare the component in the above created module
ng g c Calendar

# make sure to export CalendarComponent in CalendarModule

cd calendar

# add some "internal" components which are not exported
ng g c WeekView
ng g c DayView

# WeekView and DayView do not have to be exported, as they are used only internally

Complete CalendarModule example:

  imports: [
  declarations: [
  exports: [
export class CalendarModule { }

Creating new services

Use ng g s MyService to generate a new service. NOTE: unlike during component generation, service generation will not create a new dir for the service (although that might change in the future). The solution is to simply prefix the directory name, and the command will generate the directory and the service: ng g s my-service/my-service.


Do not do it, but if you absolutely have to edit the Webpack config manually, you can eject the CLI's Webpack config with ng eject.

Extending Angular CLI's Webpack config

Since Angular CLI version 6, there has been a way to extend the internal Webpack config which is used by the CLI. This is done by using custom builders. To check out the details on how to do this, please have a look at @angular-builders/custom-webpack. This should be enough in most cases, so you will most likely never have to eject the internal Webpack config.

One good example of extending the CLI's Webpack config can be seen in Guess.js's Angular implementation for predictive prefetching of lazy-loaded modules.

DevServer proxy

If you have issues with CORS, it is OK to temporarily use the Webpack DevServer proxy for development purposes. You can do this without ejecting the Webpack config, as instructed in the official documentation guide.

Other commands

This handbook will not cover all ng commands; please check out Angular CLI Documentation for more info.


If you are using a JS library that is not written in TypeScript, you can usually install typings separately. Install typings as a dev-dependency, for example:

npm install --save d3
npm install --save-dev @types/d3

If there are no typings available, you can create your own typings.d.ts file and write some custom typings for your needs. They do not even have to be 100% complete; they can cover only the functionality which you use.

Recommended Editor

XKCD real programmers

At Infinum, we recommend using VSCode for Angular development, as it has a great integration with TypeScript and has some handy Angular plugins:


Angular depends heavily on RxJS, so getting familiar with RxJS is pretty important. It is used for all event handling and can even be used for state management.

RxJS is the implementation of the Reactive Extensions Library for JavaScript. Angular isn't the only place where you can come across RxJS—it can also be used with Vanilla JS or some other framework. Even some Android and iOS developers use Rx for their respective platforms. While the implementations can differ a bit, learning just one of the implementations (for example RxJS) will introduce you to a lot of concepts that are common for all Rx implementations. You can then get into a heated mergeMap vs switchMap discussion with Android and/or iOS developers. Isn't that magnificent?

Please check out some RxJS tutorials if you are not familiar with Rx. Please note that there have been some breaking changes in RxJS version 6. Some of the APIs have changed (mostly the way we use operators), and many tutorials that were created earlier are now using older versions of RxJS. That being said, not much has changed conceptually, just the way you write some RxJS functionalities.

Here are some good introductory tutorials to get you started: