[Q] Can brunch trigger actions upon changes in the watched folder?

[wsw70]

I would be interested to trigger an action when the content of the app directory changes, in addition to the normal processing - something along the lines of

brunch watch --server --trigger='jekyll build'

which would also run jekyll build in addition to the processing of JS, .vue files, etc.

Is this possible? (ideally as a configuration entry)

Note: this is a copy of a question on SO (per the recommendations I posted it first there) but with 5 views I have doubts about a possible answer.