* __extensions:__ An array of extensions (without the leading dot!) that should be considered "CSS files"; this is useful when you eg. name your files `.postcss` to indicate that you are using non-standard syntax. This list of extensions will *replace* the default list of extensions, so you will need to explicitly specify `"css"` in the list, if you want to keep parsing `.css` files. Defaults to `[ "css" ]`.
* __mode:__ Whether to assume that untagged class names in your CSS (ie. those without a `:local` or `:global` tag) are local or global. Defaults to `"local"`, but you can set this to `"global"` if you want to make the class name mangling *opt-in*. You'll generally want to leave this at the default setting.
* __autoExportImports:__ Whether to automatically re-export all imports in a CSS file. When disabled, only *explicitly-defined* class names are exported from a CSS file. Defaults to `true`, ie. all imports are automatically re-exported under their local name.
* __before:__ PostCSS transforms to run *before* the ICSS transforms, ie. before imports/exports are analyzed. This is usually where you want custom PostCSS plugins to go.
* __after:__ PostCSS transforms to run *after* the ICSS transforms, ie. after mangling the class names, but before bundling it all together into a single file. You'll rarely need to use this.
* __ignoreCycles:__ When enabling this, `icssify` will handle cyclical dependencies by randomly (but deterministically) ignoring a dependency relation during sorting. This *should* be safe to do for JS files, but there's no guarantee - and if things break in strange ways when you enable this, that is probably why.
__Cyclical dependencies in CSS files are *still* not allowed__, even when enabling this setting! It's just intended to deal with cyclical JS dependencies during sorting, which are a bad practice but technically valid to have. It's opt-in to ensure that you understand the risks of enabling it.