Orders Project

Event-driven food delivery system: FastAPI + MongoDB + Redis Streams, a React frontend, running on a self-hosted Raspberry Pi Kubernetes cluster.

Live at orders.karolmarszalek.me · source on GitHub.

There is no orchestrator and no service-to-service call. Each service reacts to events on Redis Streams and emits its own.

git clone https://github.com/kkaarroollm/orders-project
cd orders-project
./scripts/setup.sh          # generates envs/mongo-keyfile
docker compose up --build

localhost serves the app, localhost/dev serves Grafana, Prometheus and the API docs.

This site covers the design: the constraints it follows from, the delivery guarantees, and the limits it runs into.

Contents

• Design
  • Constraints
  • Why choreography
  • Why Redis Streams
  • Delivery guarantees
  • What scales, and what does not
  • Where the bodies are
  • Observability
  • Scaling on backlog