Gulpifying Jekyll

gulpfile.js

/*global -$ */
'use strict';
// generated on 2015-06-12 using generator-gulp-webapp 0.3.0
var gulp = require('gulp');
var $ = require('gulp-load-plugins')();
var browserSync = require('browser-sync');
var reload = browserSync.reload;

gulp.task('styles', function () {
  return gulp.src('app/styles/main.scss')
    .pipe($.sourcemaps.init())
    .pipe($.sass({
      outputStyle: 'nested', // libsass doesn't support expanded yet
      precision: 10,
      includePaths: ['.'],
      onError: console.error.bind(console, 'Sass error:')
    }))
    .pipe($.postcss([
      require('autoprefixer-core')({browsers: ['last 1 version']})
    ]))
    .pipe($.sourcemaps.write())
    .pipe(gulp.dest('.tmp/styles'))
    .pipe(reload({stream: true}));
});

gulp.task('jshint', function () {
  return gulp.src('app/scripts/**/*.js')
    .pipe(reload({stream: true, once: true}))
    .pipe($.jshint())
    .pipe($.jshint.reporter('jshint-stylish'))
    .pipe($.if(!browserSync.active, $.jshint.reporter('fail')));
});

gulp.task('html', ['styles'], function () {
  var assets = $.useref.assets({searchPath: ['.tmp', 'app', '.']});

  return gulp.src('app/*.html')
    .pipe(assets)
    .pipe($.if('*.js', $.uglify()))
    .pipe($.if('*.css', $.csso()))
    .pipe(assets.restore())
    .pipe($.useref())
    .pipe($.if('*.html', $.minifyHtml({conditionals: true, loose: true})))
    .pipe(gulp.dest('dist'));
});

gulp.task('images', function () {
  return gulp.src('app/images/**/*')
    .pipe($.cache($.imagemin({
      progressive: true,
      interlaced: true,
      // don't remove IDs from SVGs, they are often used
      // as hooks for embedding and styling
      svgoPlugins: [{cleanupIDs: false}]
    })))
    .pipe(gulp.dest('dist/images'));
});

gulp.task('fonts', function () {
  return gulp.src(require('main-bower-files')({
    filter: '**/*.{eot,svg,ttf,woff,woff2}'
  }).concat('app/fonts/**/*'))
    .pipe(gulp.dest('.tmp/fonts'))
    .pipe(gulp.dest('dist/fonts'));
});

gulp.task('extras', function () {
  return gulp.src([
    'app/*.*',
    '!app/*.html'
  ], {
    dot: true
  }).pipe(gulp.dest('dist'));
});

gulp.task('clean', require('del').bind(null, ['.tmp', 'dist']));

gulp.task('serve', ['styles', 'fonts'], function () {
  browserSync({
    notify: false,
    port: 9000,
    server: {
      baseDir: ['.tmp', 'app'],
      routes: {
        '/bower_components': 'bower_components'
      }
    }
  });

  // watch for changes
  gulp.watch([
    'app/*.html',
    'app/scripts/**/*.js',
    'app/images/**/*',
    '.tmp/fonts/**/*'
  ]).on('change', reload);

  gulp.watch('app/styles/**/*.scss', ['styles']);
  gulp.watch('app/fonts/**/*', ['fonts']);
  gulp.watch('bower.json', ['wiredep', 'fonts']);
});

// inject bower components
gulp.task('wiredep', function () {
  var wiredep = require('wiredep').stream;

  gulp.src('app/styles/*.scss')
    .pipe(wiredep({
      ignorePath: /^(\.\.\/)+/
    }))
    .pipe(gulp.dest('app/styles'));

  gulp.src('app/*.html')
    .pipe(wiredep({
      exclude: ['bootstrap-sass-official'],
      ignorePath: /^(\.\.\/)*\.\./
    }))
    .pipe(gulp.dest('app'));
});

gulp.task('build', ['jshint', 'html', 'images', 'fonts', 'extras'], function () {
  return gulp.src('dist/**/*').pipe($.size({title: 'build', gzip: true}));
});

gulp.task('default', ['clean'], function () {
  gulp.start('build');
});

package.son

{
  "private": true,
  "engines": {
    "node": ">=0.10.0"
  },
  "devDependencies": {
    "autoprefixer-core": "^4.0.2",
    "browser-sync": "^1.8.2",
    "del": "^1.1.1",
    "gulp": "^3.6.0",
    "gulp-cache": "^0.2.2",
    "gulp-csso": "^0.2.6",
    "gulp-if": "^1.2.1",
    "gulp-imagemin": "^2.0.0",
    "gulp-jshint": "^1.5.3",
    "gulp-load-plugins": "^0.8.0",
    "gulp-minify-html": "^0.1.6",
    "gulp-postcss": "^3.0.0",
    "gulp-sass": "^1.3.3",
    "gulp-size": "^1.1.0",
    "gulp-sourcemaps": "^1.3.0",
    "gulp-uglify": "^1.0.1",
    "gulp-useref": "^1.0.2",
    "jshint-stylish": "^1.0.0",
    "main-bower-files": "^2.5.0",
    "opn": "^1.0.0",
    "wiredep": "^2.0.0"
  }
}

Can I see your _config.yml?