> For the complete documentation index, see [llms.txt](https://shoppinpal.gitbook.io/docs-shoppinpal-com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://shoppinpal.gitbook.io/docs-shoppinpal-com/3.-the-backend.md).

# 3. The Backend

## Basics

| Acronym | Technology |
| ------- | ---------- |
| M       | MongoDB    |
| E       | ExpressJS  |
| A       | AngularJS  |
| N       | Node.js    |

## Moving from Java to JavaScript

Do you have a strong background in Java? Here is a mapping that will help you gain a quick understanding of what's what in our stack:

| Java        | equivalent tech in NodeJS   | We Use           |
| ----------- | --------------------------- | ---------------- |
| Ant, Maven  | Grunt, Gulp                 | Grunt            |
| SpringBoot  | ExpressJS, Loopback         | Loopback         |
| JPA Library | sequelize, loopback-juggler | loopback-juggler |

## Loopback

Just like the industry moved from `web servers` to `application servers`. It is now moving from `application servers` to `api servers` as a matter of convenience and to facilitate faster development cycles.

Loopback is built on top of ExpressJS. It is then next logical step for those who want to write REST\~ful services.

We will cover `loopback` in this chapter.


---

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