Is the compilation of js and css done automatically?

[jzabate]

Will the compilation of css and js done automatically when it detects changes on the source files?

Sample folder structure:
[source files]
/public
/css
/css1.css
/css2.css
/js
/js1.js
/js2.js

[build files]
/public
/build
/css/build.min.css
/js/build.min.js

[wiktor-obrebski]

I no longer maintaining this project as I no more working with this technology. I would suggest using https://webpack.js.org/ or similar bundler for the task.

To answer you question directly, with my current understanding in dev mode the files are not compile, they are attached as-is, not minified and not contacted (for dev mode).

You will get minified files only in production mode. For production mode you want to compile the files only ones, in moment of deploying. In README you can found instructions how to do this.