This post is out of date; there is an updated post here.
Follow the steps below to setup sass, specifically dart-sass in the Windows Linux Subsystem.
- Download and extract the dart-sass release you are going to use, at the time of this post I opted for dart-sass-1.18.0-linux-x64.tar.gz
- Find your bash.rc,  if you setup WLSS after the Fall Creators update it will be located at  C:\Users\USERNAME\AppData\Local\Packages\{CanonicalGroupLimited.UbuntuonWindows_...}\LocalState\rootfs\home\LINUXUSER\or similar.
- Add export PATH="/path/to/dart-sass:$PATH"to the end of the file, in my caseexport PATH="/mnt/c/Users/USERNAME/Documents/GitHub/dart-sass:$PATH"
Open bash, type sass --version to see if everything worked.
