I'm not sure about "find" -- but I also use "entr" for this (and just about a billion other tasks, is there anything you can't use it for?) and I personally do something like:

  ls src/**/*.filetype | entr -r -s "some command"

And this will catch new files

`man entr` has an example for dealing with new files using the `-d` option:

    $ while true; do ls src/*.rb | entr -d make; done