fuse.js

const { FuseBox, PostCSSPlugin, LESSPlugin, CSSPlugin, Sparky } = require("fuse-box");
const { ElmPlugin } = require("./ElmPluginClass");
const path = require("path");

const homeDir = "app";
const destDir = "dist";

Sparky.task("build", () => {
  const fuse = FuseBox.init({
    homeDir,
    output: `${destDir}/$name.js`,
    plugins: [
      // Elm
      ElmPlugin(),
      
      // Less chain
      [
        LESSPlugin({ paths: [path.resolve(__dirname, "node_modules")] }),
        PostCSSPlugin([require("autoprefixer")({ map: true, browsers: ['last 2 version'] })]),
        CSSPlugin()
      ],
    ],
    debug: true
  });
  
  fuse.dev({ httpServer: false });

  // Bundle the application
  fuse.bundle("app")
    .target("browser")
    .instructions("> js/app.ts")
    .watch("js/**/*")
    .watch("elm/src/**/*")
    .watch("style/**/*");

  // Run the development server
  fuse.bundle("server")
    .target("node")
    .instructions("> [server.js]")
    .watch("server.js")
    .completed(proc => {
      proc.kill();
      proc.start();
    });
  
  fuse.run();
});

Sparky.task("copy:assets", () => Sparky.watch("./assets/**/*", { base: homeDir }).dest(`./${destDir}`));
Sparky.task("copy:vendor", () => Sparky.watch("./vendor/**/*", { base: homeDir }).dest(`./${destDir}`));
Sparky.task("copy:index", () => Sparky.watch("./index.html", { base: homeDir }).dest(`./${destDir}`));
Sparky.task("copy", ["copy:assets", "copy:vendor", "copy:index"], () => {});

Sparky.task("default", ["copy", "build"], () => {});