Does Django Work With Fly.io?
Django works excellently on Fly.io with first-class support for containerized Python applications and seamless database/storage integration.
Quick Facts
How Django Works With Fly.io
Django deploys to Fly.io as a containerized application, leveraging Docker to package your Python environment and dependencies. Fly.io provides a `flyctl` CLI tool that scaffolds a Dockerfile for Django apps, handling WSGI server configuration (typically Gunicorn) and static file serving automatically. The platform's multi-region deployment means your Django app runs close to users globally, reducing latency for both HTTP requests and database queries through Fly's managed Postgres offering.
Developer experience is streamlined: after running `flyctl launch`, you get a production-ready `fly.toml` configuration file and Dockerfile. Environment variables for `SECRET_KEY`, `DEBUG`, and `ALLOWED_HOSTS` are managed through Fly's dashboard or CLI. Django's collectstatic is automatically run during deployment, with files served from Fly's distributed cache. For databases, you can either use Fly Postgres (a managed PostgreSQL service) or connect to external databases via environment variables.
One architectural consideration: since Fly.io distributes your app across regions, ensure your sessions and caching use a shared backend (Redis via Upstash or similar) rather than in-memory storage. This prevents users from losing session state during requests to different regions.
Best Use Cases
Django on Fly.io - Settings & Deployment
pip install django gunicorn python-dotenv# settings.py (additions for Fly.io)
import os
from pathlib import Path
BASE_DIR = Path(__file__).resolve().parent.parent
SECRET_KEY = os.getenv('SECRET_KEY', 'insecure-dev-key-only')
DEBUG = os.getenv('DEBUG', 'False') == 'True'
ALLOWED_HOSTS = os.getenv('ALLOWED_HOSTS', 'localhost,127.0.0.1').split(',')
# Database
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql',
'NAME': os.getenv('DATABASE_NAME', 'postgres'),
'USER': os.getenv('DATABASE_USER', 'postgres'),
'PASSWORD': os.getenv('DATABASE_PASSWORD', ''),
'HOST': os.getenv('DATABASE_HOST', 'localhost'),
'PORT': os.getenv('DATABASE_PORT', '5432'),
}
}
STATIC_ROOT = '/app/staticfiles'
STATIC_URL = '/static/'
# fly.toml
# [env]
# DEBUG = "False"
# DATABASE_HOST = "<your-postgres-private-ip>"
# Dockerfile entrypoint
# CMD ["gunicorn", "config.wsgi:application", "--bind", "0.0.0.0:8080"]Known Issues & Gotchas
DEBUG=True in production will leak sensitive information and fail to start properly
Fix: Set DEBUG=False in fly.toml environment variables and use SECRET_KEY from a secure environment variable, not hardcoded
Static files may not be served if collectstatic fails during deployment
Fix: Ensure STATIC_ROOT is set to /app/staticfiles in settings.py and add collectstatic to the Dockerfile RUN command before starting Gunicorn
Database connections timeout when using external databases due to Fly's network architecture
Fix: Use Fly Postgres for simplicity, or configure connection pooling (PgBouncer) and appropriate timeout settings in your database URL
Local development with fly.io differs from production environment variables and secrets
Fix: Use python-dotenv to load .env files locally but never commit them; rely on flyctl secrets for production
Alternatives
- •Heroku with Django - simpler but less customizable, more expensive at scale
- •AWS App Runner + RDS - more control but requires more configuration and AWS knowledge
- •Railway with Django - similar ease to Fly.io but smaller ecosystem and less multi-region support
Resources
Related Compatibility Guides
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