# Testing and dependency injection

## Outline

### Objective

* Understand The Event Loop
* Different ways of managing concurrency in Javascript
* Query and write to some database


### Technologies used

* Javascript
* MongoDB
* Jest

### Design Patterns

* Facade
* Adapter

### What we will do

* We will write code that simulates the Javascript an event loop
* We will Apply Basic CRUD to a Database
* We will then apply various queries to get accustomed to thinking in parallel

## Pre Session

## Session



![Managing Async Code](./images/6.managing_concurency.svg)
