Scaffolding allows us to easily create a skeleton for a web application. We manually created our public directory, added middleware, created separate route files, etc. A scaffolding tool sets up all these things for us so that we can directly get started with building our application.

The scaffolder we”ll use is called Yeoman. It is a scaffolding tool built for Node.js but also has generators for several other frameworks (such as flask, rails, django, etc.). To install yeoman, enter the following command in your terminal.

$ npm install -g yeoman

Yeoman uses generators to scaffold out applications. To check out the generators available on npm to use with yeoman, head over here. For the purpose of this tutorial, we”ll use the ”generator-koa”. To install this generator, enter the following command in your terminal.

$ npm install -g generator-koa

To use this generator, enter −

yo koa

Then it”ll create a directory structure and will create the following files for you. It”ll also install the necessary npm modules and bower components for you.

create package.json
create test/routeSpec.js
create views/layout.html
create views/list.html
create public/styles/main.css
create public/scripts/.gitkeep
create controllers/messages.js
create app.js
create .editorconfig
create .jshintrc

I''m all done. Running npm install & bower install for you to install 
the required dependencies. 
If this fails, try running the command yourself.

This generator creates a very simple structure for us.

.
├── controllers
│   └── messages.js
├── public
|   ├── scripts
|   └── styles
|       └── main.css    
├── test
|   └── routeSpec.js
├── views
|   ├── layout.html
|   └── list.html
├── .editorconfig
├── .jshintrc
├── app.js
└── package.json

Explore the many generators available for Koa and choose the one that fits you right. Steps to working with all generators is the same. You”ll need to install a generator, run it using yeoman, it”ll ask you some questions and then create a skeleton for your application based on your answers.