GULP Y U NO RUN IN SERIES

gulpfile.js

var compass = require('gulp-compass'),
    concat = require('gulp-concat'),
    cssmin = require('gulp-cssmin'),
    gulp = require('gulp'),
    imagemin = require('gulp-imagemin'),
    jscs = require('gulp-jscs'),
    jshint = require('gulp-jshint'),
    livereload = require('gulp-livereload'),
    rename = require('gulp-rename'),
    replace = require('gulp-replace'),
    rimraf = require('rimraf'),
    sha1 = require('sha1'),
    uglify = require('gulp-uglify'),
    distFolder,
    jsFiles,
    hash,
    htmlFiles,
    sassFiles;

hash = sha1((new Date()).getTime());
distFolder = './dist/';
jsFiles = [
  './*.js',
  './assets/js/*.js'
];
htmlFiles = [
  './*.html'
];
sassFiles = [
  './assets/sass/styles.sass'
];

gulp.task('clean', function (done) {
  rimraf(distFolder, done);
});

gulp.task('compass', function () {
  gulp.src(sassFiles)
    .pipe(compass({
      css: 'assets/css',
      sass: 'assets/sass',
      image: 'assets/images'
    }))
    .pipe(gulp.dest('assets/css'));
});

gulp.task('lint', function () {
  gulp.src(jsFiles)
    .pipe(jshint())
    .pipe(jscs());
});

gulp.task('move', function () {
  gulp.src('api/**/*')
    .pipe(gulp.dest(distFolder + 'api'));

  gulp.src('index.html')
    .pipe(replace('app.js', hash + '.js'))
    .pipe(replace('styles.css', hash + '.css'))
    .pipe(
      replace(
        'assets/vendor/bootstrap/dist/css/bootstrap.css',
        '//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css'
      )
    )
    .pipe(
      replace(
        'assets/vendor/bootstrap/dist/js/bootstrap.min.js',
        '//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js'
      )
    )
    .pipe(
      replace(
        'assets/vendor/jquery/dist/jquery.min.js',
        '//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js'
      )
    )
    .pipe(gulp.dest(distFolder));
});

gulp.task('minify', function () {
  gulp.src('assets/css/*.css')
    .pipe(concat('styles.css'))
    .pipe(cssmin())
    .pipe(rename(hash + '.css'))
    .pipe(gulp.dest(distFolder + 'assets/css'));

  gulp.src('assets/img/*.{png,gif,jpg}')
    .pipe(imagemin())
    .pipe(gulp.dest(distFolder + 'assets/img'));

  gulp.src('assets/js/*.js')
    .pipe(concat('app.js'))
    .pipe(uglify())
    .pipe(rename(hash + '.js'))
    .pipe(gulp.dest(distFolder + 'assets/js'));
});

gulp.task('watch', function () {
  livereload.listen();

  gulp.watch([
    htmlFiles,
    jsFiles,
    'assets/css/*.css'
  ])
    .on('change', livereload.changed);

  gulp.watch(jsFiles, [
    'lint'
  ]);

  gulp.watch(sassFiles, [
    'compass'
  ]);
});

gulp.task('default', [
  'watch'
]);

gulp.task('build', [
  'clean',
  'compass',
  'lint',
  'minify',
  'move'
]);

sigh

[19:29:43] Using gulpfile ~/Sites/xxx/gulpfile.js
[19:29:43] Starting 'clean'...
[19:29:43] Starting 'compass'...
[19:29:43] Finished 'compass' after 11 ms
[19:29:43] Starting 'lint'...
[19:29:44] Finished 'lint' after 114 ms
[19:29:44] Starting 'minify'...
[19:29:44] Finished 'minify' after 14 ms
[19:29:44] Starting 'move'...
[19:29:44] Finished 'move' after 5.08 ms
[19:29:44] Finished 'clean' after 155 ms
[19:29:44] Starting 'build'...
[19:29:44] Finished 'build' after 12 μs
[19:29:44] gulp-imagemin: Minified 0 images (saved 0 B - 0%)
unchanged assets/sass/styles.sass

Probably best not to use gulp.start but here's a quick fix:

gulp.task('build', ['clean'], function() {
    return gulp.start('compass', 'lint', 'minify', 'move');
});

Hmmm, gulpjs/gulp#426 (comment)

I was looking for something like gulp.start, but in the end I just use run-sequence instead. It does what I want, just slightly annoyed that there's no way to specify directly in gulp whether tasks should be concurrent or series, whereas you can in Grunt.