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Docker FastAPI Nginx Redis

Dockerising a FastAPI App with Compose, Nginx & Redis

December 2025 · 7 min read

Running uvicorn main:app locally is easy. Running it in production with a database, cache layer, and reverse proxy — that's where Docker Compose earns its keep. Here's the setup I use for most of my FastAPI projects.

The Stack

A typical FastAPI project I deploy looks like this:

All four services defined in one docker-compose.yml, with health checks and dependency ordering.

The Dockerfile (Multi-Stage)

Multi-stage builds keep the final image small by separating the build environment from the runtime:

# Stage 1: Install dependencies
FROM python:3.12-slim AS builder
WORKDIR /app
COPY requirements.txt .
RUN pip install --no-cache-dir --prefix=/install -r requirements.txt

# Stage 2: Runtime
FROM python:3.12-slim
WORKDIR /app
COPY --from=builder /install /usr/local
COPY ./src .

# Non-root user for security
RUN adduser --disabled-password --no-create-home appuser
USER appuser

EXPOSE 8000
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]

Key details: the --no-cache-dir flag avoids bloating the image with pip cache. Running as a non-root user is a basic security practice that many tutorials skip.

Docker Compose

services:
  app:
    build: .
    env_file: .env
    depends_on:
      db:
        condition: service_healthy
      redis:
        condition: service_healthy
    networks:
      - backend

  db:
    image: postgres:16-alpine
    environment:
      POSTGRES_DB: ${DB_NAME}
      POSTGRES_USER: ${DB_USER}
      POSTGRES_PASSWORD: ${DB_PASS}
    volumes:
      - pgdata:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U ${DB_USER}"]
      interval: 5s
      retries: 5
    networks:
      - backend

  redis:
    image: redis:7-alpine
    command: redis-server --requirepass ${REDIS_PASS}
    healthcheck:
      test: ["CMD", "redis-cli", "-a", "${REDIS_PASS}", "ping"]
      interval: 5s
      retries: 5
    networks:
      - backend

  nginx:
    image: nginx:alpine
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf:ro
      - ./nginx/certs:/etc/nginx/certs:ro
    depends_on:
      - app
    networks:
      - backend

volumes:
  pgdata:

networks:
  backend:

Nginx Configuration

Nginx sits in front of Uvicorn and handles things the app server shouldn't:

upstream fastapi {
    server app:8000;
}

server {
    listen 80;
    server_name your-domain.com;

    location / {
        proxy_pass http://fastapi;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }

    location /static/ {
        alias /var/www/static/;
        expires 30d;
        add_header Cache-Control "public, immutable";
    }
}

The upstream block references the Docker service name app — Docker's internal DNS resolves it automatically. No IP addresses needed.

Using Redis for Caching

In FastAPI, I use Redis for caching expensive database queries:

import redis
import json, os

r = redis.Redis(
    host="redis",
    port=6379,
    password=os.environ["REDIS_PASS"],
    decode_responses=True
)

async def get_device_summary(device_id: str):
    cache_key = f"device:{device_id}:summary"
    cached = r.get(cache_key)
    if cached:
        return json.loads(cached)

    # Expensive DB query
    summary = await db.fetch_device_summary(device_id)
    r.setex(cache_key, 300, json.dumps(summary))  # 5 min TTL
    return summary

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