Using CSS and JavaScript in themes

The theme compiler

Shopware uses a compiler to concatenate and minify resource files like CSS and JavaScript to single compressed files. This reduces the file size and the amount of server requests. It is highly recommended to add your files to the compiler, too. The generated files are added to the template automatically, so you don't have to worry about including your files at all.

Before you add your files to the theme compiler you have to place them in the correct directory structure inside your custom theme. Here is an example directory structure:

└── frontend
    └── _public
        └── src
            ├── css
            │   └── example.css
            └── js
                └── example.js

As the second step you will have to define the CSS or JavaScript files you would like to use inside your custom theme. This can be done by defining the corresponding configuration variables in the Theme.php file, where you add the specific file paths.

Since Shopware 5.4, it's possible to manipulate the chain of inheritance by discarding Less/JavaScript, defined by another theme. You can find detailed information here.

Add CSS files

Add the file paths to the $css variable in your Theme.php file, relative to the _public directory.

protected $css = [

Add JavaScript files

Add the file paths to the $javascript variable in your Theme.php file, relative to the _public directory.

protected $javascript = [

Compiling files

Every time you add changes to your LESS, CSS or JavaScript files the corresponding theme files have to be compiled. There are two ways of doing this.


During production mode you can start the compiler via the administration panel in the cache and performance module. Go to Configuration -> Caches & Performance -> Caches and check the Compile themes option.


For development you have the option to disable the compiling in Configuration -> Theme Manager -> Settings -> Disable compiler caching.
But the best way for developing is to use the grunt file watcher.

Asynchronous JavaScript

Since Shopware 5.3 we are loading the concatenated JavaScript file asynchronously. This improves the first rendering of the page also known as page speed. If you are using the compiler you should not worry about a thing, because your script is loaded together with all other Shopware scripts.

If there is a reason for you to implement your script in a different way, please be aware of possible race conditions that could occur. When you need some parts from the main script as a dependency (for example jQuery) there is a new callback method which you can use to wait for the main script to load.

document.asyncReady(function() {
    // do your magic here