# Overview

## Technology Stack

We have built our back ends primarily using [Python](https://www.python.org/), [Django](https://www.djangoproject.com/), and [Django Rest Framework](https://www.django-rest-framework.org/).

{% hint style="info" %}
We recommend getting familiar with the basics of each technology before contributing to one of our back ends.
{% endhint %}

## Code Repositories

Each service has a back end code repository in the [Ocado Technology](https://github.com/ocadotechnology) GitHub organisation which follows the naming convention:

```
codeforlife-{service}-backend
```

[View](https://github.com/orgs/ocadotechnology/repositories?q=codeforlife-+-backend) our back end repos on GitHub.

### Template

To speed up the process of creating a new back end repo, we created the template repo [codeforlife-template-backend](https://github.com/ocadotechnology/codeforlife-template-backend) which can be used to scaffold a new service's back end repo. Read [here](https://docs.github.com/en/repositories/creating-and-managing-repositories/creating-a-repository-from-a-template) on how to create a repo from a template.

{% hint style="success" %}
After creating a repo from the template, run a case-insensitive search across all files for **replace-me**. Replace these strings with the appropriate value; this will most likely be the service's name.
{% endhint %}

## CI/CD Pipelines

In order to avoid repeating the same pipelines in every back end service, we centrally define the pipelines in our [workspace repo](https://github.com/ocadotechnology/codeforlife-workspace/tree/main/.github/workflows), and reference them in each back end service. In GitHub's terminology, these are referred to as [reusable workflows](https://docs.github.com/en/actions/sharing-automations/reusing-workflows).

There are 2 main pipelines in each back end service.

### main.yaml

The main pipeline for each back end service which simply reuses the [backend](https://github.com/ocadotechnology/codeforlife-workspace/blob/main/.github/workflows/backend.yaml) pipeline located in the workspace. This pipeline is responsible for testing and deploying a back end service.

You can see an example of this pipeline in the [back end template repo](https://github.com/ocadotechnology/codeforlife-template-backend/blob/development/.github/workflows/main.yaml).

### contributing.yaml

This pipeline is responsible for managing the process of contributing to our code base, such as checking our contributors have signed our contributor agreement, auto-assigning/-unassigning contributors to issues, and more.

You can see an example of this pipeline in the [back end template repo.](https://github.com/ocadotechnology/codeforlife-template-backend/blob/development/.github/workflows/contributing.yaml)

## Python Package

To avoid repeating code across 2 or more back ends, we have created the repo [codeforlife-package-python](https://github.com/ocadotechnology/codeforlife-package-python) which automatically tests and releases new version of the package using [semantic versioning](https://semver.org/). These versioned packages can then be installed into our Python virtual-environments (.venv).

Learn more about our Python package [here](https://code-for-life.gitbook.io/python-package).