Workspace messaging with persistent channels, real-time WebSocket delivery, search indexing, and app integrations.
Difficulty: intermediate
Tags: collaboration, real-time, websockets, search
Slack powers real-time communication for millions of teams with persistent channels, threaded conversations, file sharing, and a rich app integration ecosystem. The architecture uses WebSocket connections via API Gateway for real-time message delivery, ECS for stateless microservices, and OpenSearch for full-text message indexing. Well-suited for teams building enterprise collaboration tools with channels, threads, and real-time presence indicators.