Back End

Django and the data underneath it: models, the ORM, REST APIs, authentication, background work, and the databases that store the result.

Author

Benedict Thekkel

This is the largest site in the collection and the most opinionated, because it is written from actually shipping Django applications rather than from surveying the field. Django and Django REST Framework are assumed throughout.

The shape is roughly the order you meet the problems. Model your data, query it without generating a thousand queries, expose it as an API, decide who is allowed to call it, move the slow parts into the background, and store it somewhere that survives a restart. The database folder covers that last part independently, because the choice outlives any one application.

Getting Started with Django

Page	Covers
Django Basics	The foundation, and by far the longest page here at 150 cells
Django Stack	The pieces and how they fit
DjangoX	A preconfigured starting point
Django Templates	Starter templates, from barebones to full SaaS platforms

Models and Data

Page	Covers
Model Design	Getting the schema right, which is the decision everything else inherits
Saving Objects	How writes actually go through
JSONField	Storing and querying JSON in the database when a rigid schema does not fit
Migrations	Changing the schema without losing data
Validators	Enforcing conditions before a value reaches the database, across models, forms, and serializers

Querying the ORM

Five pages on the same subject, because this is where Django applications get slow.

Page	Covers
Query Filters	How the QuerySet API turns Pythonic queries into SQL
QuerySets	The object you are actually manipulating
Query Math	Aggregations, arithmetic, and window functions, all without dropping to raw SQL
Managers and QuerySets	Encapsulating query logic where it belongs instead of scattering it through views
django-filter	Filtering a queryset from form input, wired into class-based views and DRF
Indexing and Caching	The two levers for query optimisation

REST APIs

Page	Covers
REST API Standard	The architectural style itself, before any framework
DRF Basics	What the toolkit gives you
DRF Quickstart	The fastest path to a working API
DRF Tutorial	The longer worked version
Serialization	Turning models into JSON and back
Views	The request handlers in between
Nested Routers	Routing resources that belong to other resources
DRF Spectacular	Generating OpenAPI 3.0 schemas, which is what feeds Swagger UI, ReDoc, and Postman
DataTables Server-Side	Delegating filtering, sorting, and pagination from the browser table to DRF

Authentication, Permissions, and Secrets

Page	Covers
Authentication	DRF’s authentication system
User Models	Modelling users, which is worth getting right before the first migration
Allauth	Third-party accounts and social login
Permissions	Controlling who can reach which endpoint
Permission Rules	Object-level permissions expressed as plain Python functions, via django-rules
Permission Types	Access control models for SaaS specifically, and how to choose between them
Security	Secure coding practice, audits, and the tooling that finds problems
Secrets	Keeping credentials out of the repository

Admin and Forms

Page	Covers
Django Admin	Customising the admin from the basics to the advanced techniques
Admin Unfold	Modernising the admin interface without rebuilding it
Forms	The built-in form layer
Crispy Forms	Rendering them without hand-writing the markup
npm in Django	Managing front-end dependencies such as Bootstrap from inside a Django project

Background Work and Real Time

Page	Covers
django-q	A task queue and scheduler built for Django, simpler than the alternative
Celery	The distributed alternative, for when django-q is not enough
Channels	WebSockets and async protocols, which is what makes chat, notifications, and live updates possible
MQTT	The publish/subscribe broker, for IoT devices and sensors feeding the backend

Operations

Page	Covers
Custom Commands	Writing your own `manage.py` subcommands
Django Commands	The built-in ones
Testing	pytest against a Django project
Backups	django-dbbackup for database and media, to local or cloud storage
Email	Configuring and sending mail
Import and Export	Moving data in and out as CSV, Excel, or JSON, from the admin or programmatically
PDF Generation	WeasyPrint rendering HTML and CSS into invoices, reports, and receipts
Constance	Admin-editable settings stored in the database, which gives you feature flags and thresholds without a redeploy
Recovery Metrics Setup	The project-specific setup notes

Databases

Independent of Django, because the choice outlives the application.

Page	Covers
SQL	The language itself: querying, inserting, updating, deleting
PostgreSQL	Database structure and practice, for the default choice
PostgreSQL Setup	Getting it running
PostgreSQL Extensions	What extensions are, how they work, and a catalogue grouped by use case
TimescaleDB	Time-series inside Postgres, driven from Django
MySQL and MariaDB	The other major open-source relational option
SQLite	Serverless and zero-configuration, for embedded use and development
DuckDB	The analytical counterpart, aimed at data and ML work rather than transactions
Redis	In-memory store used as cache, broker, and database, with the data structures that make it flexible
InfluxDB	The time-series backend, covered at length

Not Covered Yet

No FastAPI or Flask. Django is the only web framework here, so there is no comparison against the async-first alternatives.
Nothing on deployment. Getting the application onto a server is covered in Web Development and IaaS, not here, so this site stops at the code.
No API versioning or deprecation strategy, despite the depth of DRF coverage.
Nothing on rate limiting or throttling as a subject of its own.
No database replication, sharding, or connection pooling. The database pages stop before scale.
QuerySets, Indexing and Caching, and Email are thin at four to five cells, and indexing in particular deserves more given how often it is the answer.
Django/03_2_Permission _Types.ipynb has a stray space in its filename, which is why its URL looks wrong.