Mohammad
Rajaei

Learn how REST, streaming, SSE, WebSocket, gRPC, polling, GraphQL, WebRTC, MQTT, and more move data between clients and servers. Everything runs in the browser — step animations, failure scenarios, side-by-side compare, and a short chooser quiz. No accounts or live traffic.

• Step simulator with play/pause, speed control, and looping packet motion
• Failure scenarios: timeouts, reconnects, rate limits, ICE failure, and more
• Comparison table and dual-protocol compare derived from protocol traits
• Protocol chooser quiz — three questions → recommended protocol
• Shareable deep links like #websocket/happy/3 or #rest/rate-limit/1

Start with SQL fundamentals, then internals and families, and finish able to choose a storage architecture for workload and guarantees — and grow from a handful of requests to billions. Everything runs in the browser: leveled lessons, Mermaid diagrams, concept simulators, a workload chooser quiz, side-by-side compare, shareable deep links, and local progress. No accounts required.

• Seven levels — Beginner → Intermediate → Advanced → Distributed → Data architecture → DB engineering → Architect
• Lesson reader with prose, SQL examples, ASCII + Mermaid diagrams, and takeaways
• Concept simulators for Postgres path, transactions, replication, polyglot, and more data models
• Database chooser starting with “why not PostgreSQL?”, then adaptive questions → engine + checklist
• Comparison matrix, localStorage progress, quick find (Ctrl/⌘ K), and deep links like #beginner/joins

Build computer vision pipelines visually — inspect every pixel transformation in real time, then export clean, production-ready Python the moment you're happy with the result. Assemble your pipeline as a graph, watch every node's output update live, and walk away with production code — not a black box.

• Visual graph editor for computer vision pipelines
• Live per-node output inspection while you tune parameters
• Breaks the tweak → run → save → squint debug loop
• Export production-ready Python when the pipeline looks right