API & Backend
SSE vs WebSockets in FastAPI: Real-Time Communication for AI Applications
Compare Server-Sent Events (SSE) and bi-directional WebSockets for LLM token streaming, financial feeds, and interactive chat backends.
Why SSE Is the De Facto Standard for LLM Output Streaming
For one-way server-to-client token streams (like ChatGPT completions), SSE is superior to WebSockets because it operates over standard HTTP/2, supports automatic reconnection, and bypasses proxy firewall restrictions.
Related Technical Guides
Deepen your understanding with these closely related production architectures and tutorials:
Real-Time AI Streaming with FastAPI and Google Gemini API (SSE)
Learn how to build low-latency Server-Sent Events (SSE) streaming endpoints in FastAPI using the official Google GenAI SDK and structured tool calling.
LLM Structured Outputs: Zero-Error JSON Extraction with Pydantic v2, JSON Schema & Instructor
Guarantee 100% schema compliance from LLMs using Pydantic v2, grammar-constrained decoding, and the Instructor library without retry overhead.
FastAPI Async Architecture: Asyncio Event Loop & High-Concurrency Best Practices
Master async def vs sync def in FastAPI, avoid blocking the asyncio event loop, and handle tens of thousands of concurrent requests smoothly.