gulpfile.js

// Project configuration
var project     = 'bare'
  , build       = './build/'
  , dist        = './dist/'
  , source      = './src/' // 'source' instead of 'src' to avoid confusion with gulp.src
  , lang        = 'languages/'
  , fonts       = 'fonts/'
  , bower       = './bower_components/'
;

// Initialization sequence
var gulp        = require('gulp')
  , gutil       = require('gulp-util')
  , plugins     = require('gulp-load-plugins')({ camelize: true }) // This loads all modules prefixed with "gulp-" to plugin.moduleName
  , del         = require('del')
  , lazypipe    = require('lazypipe')
  , merge       = require('merge-stream')
;

var styles_sass = lazypipe()
  .pipe( plugins.sass, { 
    includePaths: [bower, source+'scss'], 
    errLogToConsole: true 
  })
  .pipe( plugins.autoprefixer, 
    'last 2 versions', 'ie 9', 'ios 6', 'android 4');
var styles_min = lazypipe()
  .pipe( plugins.rename, { suffix: '.min' })
  .pipe( plugins.minifyCss, { keepSpecialComments: 1 });
var onError = function(err) { console.log(err) }

gulp.task('styles', function() {
  return gulp.src([source+'scss/*.scss', '!'+source+'scss/_*.scss'])
    .pipe(styles_sass().on('error', onError))
    .pipe(gulp.dest(build))
    .pipe(styles_min().on('error', onError))
    .pipe(gulp.dest(build))
});

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