We’ve recently started using the in-built CSS and styling features in mendix 9 to make our stylesheets easier to maintain, and hostable on the appstore.
One thing we have lost when moving away from using gulp to compile our stylesheets is the ability to minify our final CSS file, and other compile options.
https://rstudio.github.io/sass/reference/sass_options.html
This is the full list of compile options from the sass documentation – it would be great if these were exposed in the app settings to give us more control of what our output is!