hnjm/cecochat

System design and partial implementation of a chat for 10-100 millions active users based on Kafka, Cassandra, gRPC, Redis, Docker, .NET 5, ASP.NET

Chat engine for millions of users

• Messaging in real-time
  • Send and receive messages, (un)react with emojis
  • Notifications when a message has been processed
  • Multiple clients for the same user
• Chats
  • Indication for new messages
  • Review history at a random point in time
• Users
  • Registration and authentication
  • Change password, edit trivial profile data
  • Profiles with full and public-only data

Check out what next needs to be implemented. I appreciate all comments so feel free to use the Discussions tab.

Technology

• System design based on microservice architecture
• Implementation based on cloud agnostic technologies
• Configurable, observable, containerized and runnable, deployable local environment

Code

Documentation

• Intro
  • Capabilities
  • Overall design
  • Technologies
• Research
  • Concurrent connections limit
  • Calculations
  • Messaging traffic
  • Message IDs
  • Reliable messaging and consistency
• Design
  • Messaging
  • User chats, chat history
  • User profiles
  • Clients
  • Configuration
  • Observability
  • Deployment
• Development
  • Local run prerequisites
  • Local run in Docker
  • Local run in Minikube
  • CI pipeline
• Load test using 2 machines
• What next

Design