Which CSS Minifier tool does Bootstrap 5 use?

[coudrak]

Hi!

When I try to minify the CSS of Bootstrap 5, most of tools like https://www.cleancss.com/css-minify/ fail with errors (probably because of variables).

I found this one which works to generate a result https://www.toptal.com/developers/cssminifier BUT it changes the order of CSS, and for example the classes col or col-12 have priority on the classes col-md-... on desktop! It breaks the grid on desktop...

The minified CSS file provided with Bootstrap in /dist/ works, so I wonder which tool is used to generate it?

Thanks!

[julien-deramond]

Hi @coudrak
We use clean-css via clean-css-cli in our package.json:

bootstrap/package.json

Line 51 in 7a42268

"css-minify-main": "cleancss -O1 --format breakWith=lf --with-rebase --source-map --source-map-inline-sources --output dist/css/ --batch --batch-suffix \".min\" \"dist/css/*.css\" \"!dist/css/*.min.css\" \"!dist/css/*rtl*.css\"",

[coudrak]

Ah ok, thanks!