sample gulpfile

gulpfile.js

var gulp = require("gulp")
var gulpif = require( 'gulp-if')
var jade = require("gulp-jade")
var stylus = require("gulp-stylus")
var autoprefixer = require("gulp-autoprefixer")
var minifyImg = require("gulp-imagemin")
var changed = require("gulp-changed")
var uglify = require("gulp-uglify")
var minifyCss = require("gulp-minify-css")
var browserSync = require('browser-sync')
var sourcemaps = require("gulp-sourcemaps")
var plumber=require("gulp-plumber")
var postcss=require("gulp-postcss")
var util=require("gulp-util")

var cssgrace=require('cssgrace')
var reload=browserSync.reload

var error = function(e){
    util.beep()
    util.log(e.toString())
}

var paths={
    //build
    //html:"build/html",
    html:"build",
    css:"build/css",
    js:"build/js",
    image:"build/img",
    json:"build/data",
    //develop
    jade:"src/jade/*.jade",
    img:"src/img/**",
    stylus:"src/stylus/*.styl",
    data:"src/data/*.*"
}

gulp.task("browser-sync",function(){
    browserSync({
        server:{
            baseDir:"build"
        }
    })
    gulp.watch(paths.jade,["html",reload]),
    gulp.watch(paths.stylus,["css",reload]),
    gulp.watch("src/js/**",["js",reload])
    gulp.watch(paths.img,["img",reload])
})

gulp.task("html",function(){
    return gulp.src(paths.jade)
        .pipe(plumber({"errorHandler":error}))
        .pipe(jade())
        .pipe(gulp.dest(paths.html))
})

gulp.task("css", function () {
    var processors = [
        cssgrace
    ];
    return gulp.src([paths.stylus,"bower_components/typo.css/typo.css"])
        .pipe(plumber({"errorHandler":error}))
        .pipe(gulpif("*.styl",stylus()))
        .pipe(autoprefixer())
        .pipe(postcss(processors))
        .pipe(minifyCss({compatibility:"ie7"}))
        .pipe(gulp.dest(paths.css))
})

gulp.task("js", function () {
    return gulp.src(['src/js/**/*.js',
        '!src/js/**/*.min.js',
        'bower_components/jquery/dist/jquery.min.js',
        'bower_components/json2/json2.js'
    ])
        .pipe(plumber({"errorHandler":error}))
        .pipe(uglify())
        .pipe(gulp.dest(paths.js))
})

gulp.task("img",function(){
    return gulp.src(paths.img)
        .pipe(plumber({"errorHandler":error}))
        .pipe(minifyImg())
        .pipe(gulp.dest(paths.image))
})

gulp.task("data",function(){
    return gulp.src(paths.data)
        .pipe(plumber({"errorHandler":error}))
        .pipe(gulp.dest(paths.json))
})

gulp.task("default", function(){
    gulp.run("html", "css", "js","img","data","browser-sync");
})