gulpfile.js

var gulp = require("gulp");
var path = require("path");
var sourcemaps = require("gulp-sourcemaps");
var ts = require("gulp-typescript");
var del = require("del");
var concat = require("gulp-concat")
var runSequence = require("run-sequence");

// SERVER
gulp.task("clean", function () {
    return del("dist")
});

gulp.task("build:server", function () {
    var tsProject = ts.createProject("server/tsconfig.json");
    var tsResult = gulp.src("server/**/*.ts").pipe(sourcemaps.init()).pipe(ts(tsProject))

    return tsResult.js.pipe(sourcemaps.write()).pipe(gulp.dest("dist"))
});

// CLIENT

/*
  jsNPMDependencies, sometimes order matters here! so becareful!
*/
var jsNPMDependencies = [
    "angular2/bundles/angular2-polyfills.js",
    "es6-shim/es6-shim.js",
    "systemjs/dist/system.src.js",
    "rxjs/bundles/Rx.js",
    "angular2/bundles/angular2.dev.js",
    "angular2/bundles/http.dev.js",
    "angular2/bundles/router.dev.js"
]

gulp.task("build:index", function () {
    var mappedPaths = jsNPMDependencies.map(file => { return path.resolve("node_modules", file) })

    //Let"s copy our head dependencies into a dist/libs
    var copyJsNPMDependencies = gulp.src(mappedPaths, { base: "node_modules" }).pipe(gulp.dest("dist/libs"))

    //Let"s copy our index into dist   
    var copyIndex = gulp.src(["client/**/*.css", "client/**/*.html"]).pipe(gulp.dest("dist"))

    return [copyJsNPMDependencies, copyIndex];
});

gulp.task("build:app", function () {
    var tsProject = ts.createProject("client/tsconfig.json");
    var tsResult = gulp.src(["client/**/*.ts"]).pipe(sourcemaps.init()).pipe(ts(tsProject))

    return tsResult.js.pipe(sourcemaps.write()).pipe(gulp.dest("dist"))
});

gulp.task("build", function (callback) {
    runSequence("clean", "build:server", "build:index", "build:app", callback);
});

gulp.task("default", ["build"]);