Koala is a gui for Less, Sass, Compass and CoffeeScript. Koala can run in windows, mac, and linux.
There are many alternatives to Koala for Windows and since it's discontinued a lot of people are looking for a replacement. The most popular Windows alternative is Prepros. It's not free, so if you're looking for a free alternative, you could try Scout-App or Crunch!. If that doesn't suit you, our users have ranked 12 alternatives to Koala and four of them are available for Windows so hopefully you can find a suitable replacement.