# Managing CSS and JavaScript in Chamilo.
The folder "assets" will be processed by the js library Webpack Encore and the result will be saved in public/build folder.
For this, we first need to install yarn.
Yarn is a JavaScript dependencies manager similar to Bower (that we also used for development in Chamilo 1.11.x),
only that Bower is deprecated now.
To install yarn v2, follow the installation instructions here https://yarnpkg.com/getting-started/install
After the installation run this command in the Chamilo root:
``yarn install``
yarn will read the dependencies in the **packages.json** file and save the dependencies in the 'node_modules' folder (which must **NOT** be committed** to the Chamilo repository).
To upgrade packages:
``yarn up``
# Configuring Encore/Webpack
Webpack takes CSS, JS and other files and generates tidy single-files to attach to your web package.
The behaviour of how packages will be processed is described here: "webpack.config.js".
Then, to create the public/build contents, run one of the following commands:
To compile assets just once:
``yarn run encore dev``
To compile assets and minify & optimize them:
``yarn run encore production``
For more detail information please visit:
https://symfony.com/doc/current/frontend.html
