Gulp file to concat coffee script and javascript

gulpfile.js

gulp.task('scriptspre', function() {
  return gulp.src([
                    'project/assets/scripts/scriptspre.coffee',
                    'bower_components/modernizr/modernizr.js'
                  ])
    .pipe(coffee())
    .pipe(sourcemaps.init())
    .pipe(concat('pre.js'))
    .pipe(sourcemaps.write())
    .pipe(gulp.dest('build/assets/js/'));
});