Gulp recipe

gulpfile.js

var gulp    = require('gulp'),
	fs      = require('fs'),
	rimraf  = require('gulp-rimraf'),
	Q       = require('q'),
	copyFilesTo;

//	clean the target folder, so we can copy there the new build output
gulp.task('cleanTargetFolder', function(done){

	gulp
	//	get everything except the gulpfile
	.src(['*', '!gulpfile.js', '!dev'], { read: false })
	.pipe(rimraf())
	.on('end', function(){
	
		console.log('target folder ' + __dirname + ' is now clean');
		done();
	});

});

copyFilesTo = function(path, cb){

	gulp
	.src('dev/**/*')
	//.pipe(doSomethingHere())
	.pipe(gulp.dest(path))
	.on('end',cb);
};

//	we have a task that makes our new directories, which depends on the 'cleanTargetFolder' task
gulp.task('makeDirs', ['cleanTargetFolder'], function(){

	var dirNames = ['A','B','C'],
		deferred = Q.defer();

	dirNames.forEach(function(dir, index){
	
		fs.mkdirSync(dir);	//	we use the sync version so we are sure
		                    //	the directories are there when we exit the task

		//	copy our files ( after we do whatever we want on them )
		copyFilesTo(dir,function(){
		
			if((index+1) === dirNames.length){
				//	when in last directory, resolve the promise so the task can finish
				deferred.resolve();
			}
		});
	});

	return deferred.promise;
});

//	depends only on makeDirs
gulp.task('default', ['makeDirs'],function(){
	//	deafult task here
});