gulp hangs

[franz-see]

$ gulp
[16:20:40] Using gulpfile ~/myroject/htdocs/wp-content/themes/timber-foundation-theme/gulpfile.js
[16:20:40] Starting 'scripts'...
[16:20:40] Finished 'scripts' after 14 ms
[16:20:40] Starting 'styles'...
[16:20:40] Finished 'styles' after 4.18 ms
[16:20:40] Starting 'images'...
[16:20:40] Starting 'setWatch'...
[16:20:40] Finished 'setWatch' after 13 μs
[16:20:40] Starting 'watch'...
[16:20:40] Finished 'watch' after 25 ms
[16:20:40] Finished 'images' after 42 ms
[16:20:40] Starting 'build'...
[16:20:40] Finished 'build' after 12 μs
[16:20:40] Starting 'default'...
[16:20:40] Finished 'default' after 7.74 μs
[16:20:40] [gulp-sass] file to import not found or unreadable: bourbon
Current dir: /Users/franz/myroject/htdocs/wp-content/themes/timber-foundation-theme/src/scss/ on line 20 in /Users/franz/myroject/htdocs/wp-content/themes/timber-foundation-theme/src/scss/main.scss

And then that's it. it hangs there until I hit a Ctrl+C.