I have used the gulp-order plugin but it is not always successful as you can see by my stack overflow post gulp-order node module with merged streams. When browsing through the Gulp docs I came across the streamque module which has worked quite well for specifying order of in my case concatenation. https://github.com/gulpjs/gulp/blob/master/docs/recipes/using-multiple-sources-in-one-task.md
Example of how I used it is below
var gulp = require('gulp');
var concat = require('gulp-concat');
var handleErrors = require('../util/handleErrors');
var streamqueue = require('streamqueue');
gulp.task('scripts', function() {
return streamqueue({ objectMode: true },
gulp.src('./public/angular/config/*.js'),
gulp.src('./public/angular/services/**/*.js'),
gulp.src('./public/angular/modules/**/*.js'),
gulp.src('./public/angular/primitives/**/*.js'),
gulp.src('./public/js/**/*.js')
)
.pipe(concat('app.js'))
.pipe(gulp.dest('./public/build/js'))
.on('error', handleErrors);
});