entr

Run arbitrary commands when files change. More information: http://eradman.com/entrproject/.

ag -l | entr make

ls *.c | entr 'make && make test'

ls *.rb | entr -r ruby main.rb

ls *.sql | entr psql -f /_

echo my.sql | entr -cp psql -f /_

find src/ | entr -s 'make | sed 10q'

ls *.js | entr -r node app.js