I found that I had to do a few tweaks in order for changes to sass files to trigger a recompile in watch mode. By default, I found that only changes to files imported directly by my js files would trigger a reload.
I changed your code (in #36) to use SASS statistics for used files, because it seems to be more reasonable and also I don't want to use any more external dependencies. Thanks for your PR!
I found that I had to do a few tweaks in order for changes to sass files to trigger a recompile in watch mode. By default, I found that only changes to files imported directly by my js files would trigger a reload.