gulp setting package

gulpfile.js

/**
 * 
 * @authors Ted Shiu (ted@sitetag.us)
 * @date    2016-07-01 11:40:47
 */

var gulp = require('gulp'),
    watch = require('gulp-watch'),
    cssmin = require('gulp-cssmin'),
    uglify = require('gulp-uglify'),
    concat = require('gulp-concat');

var css ='',
    device = '',
    js = '';
gulp.task('default', function (cb) {
    var options = {};
    watch('./**/*.css', options, function (e) {
        // console.log('e:'+JSON.stringify(e));
        console.log(new Date() + ' -- ' + e.history[0].replace(e.base, ''));
        // console.log('\n');
        gulp.src('./dev/css/*.css')
        .pipe(concat('site.css' , {newLine: '\n'}))
        .pipe(cssmin())
        .pipe(gulp.dest('./build/'));
    });
    watch('./**/*.js', options, function (e) {
        // console.log('e:'+JSON.stringify(e));
        console.log(new Date() + ' -- ' + e.history[0].replace(e.base, ''));
        // console.log('\n');
        gulp.src('./dev/js/*.js')
        .pipe(concat('site.js' , {newLine: '\n'}))
        .pipe(uglify())
        .pipe(gulp.dest('./build/js/'));
    });
});

package.json

{
  "name": "",
  "version": "",
  "devDependencies": {
    "gulp": "^3.9.0",
    "gulp-concat": "^2.6.0",
    "gulp-cssmin": "^0.1.7",
    "gulp-uglify": "^1.5.3",
    "gulp-watch": "^4.3.5"
  }
}