Is it possible create one js file (like build version ) of extjs application without app.js

Is it possible create one js file (like build version ) of extjs
application without app.js

Can anybody tell Is it possible create one js file (like build version )
of extjs application without app.js.If have include the js application it
will work in another application .If not if am build the application using
app.js.is it possible to remove app.js from build version?
Thanks