Gradio is a full-stack Python library and web framework for rapidly creating interactive web UIs for machine learning models, APIs, or any Python function. It provides a high-level Interface class for simple demos, a flexible Blocks API for custom layouts and event-driven apps, and a ChatInterface for chatbot applications. The backend is built on FastAPI and Uvicorn, serving both a REST API and WebSocket-based streaming. The frontend is a Svelte 5 / TypeScript application with per-component packages, a SvelteKit SSR app, and a standalone SPA that can be embedded via a custom HTML element. The library includes a rich component library (30+ input/output widgets), layout primitives (Row, Column, Tabs, Accordion, Sidebar), theming support, internationalization, and a CLI for development, deployment, and custom component creation. It also provides official Python and JavaScript client libraries for programmatic access to Gradio apps, and supports MCP (Model Context Protocol) for tool/resource integration. The repository contains over 100 runnable demos covering a wide range of ML use cases (image classification, text generation, speech recognition, object detection, chatbots, etc.), many of which integrate with Hugging Face models and datasets. While primarily an application framework, the extensive demo collection and focus on ML model visualization give it a secondary data/research character.

FastRTC is a Python library that enables developers to build real-time audio/video streaming applications with minimal code. It provides a high-level `Stream` class that integrates with Gradio for automatic UI generation and supports both WebRTC and WebSocket protocols. The library includes built-in handlers for voice activity detection (VAD) via Silero, speech-to-text via Moonshine, text-to-speech via Kokoro/Cartesia, and turn-taking logic. It also offers TURN credential helpers for Cloudflare, Twilio, and Hugging Face. The architecture revolves around defining a handler function that processes media chunks, wrapping it with turn-taking decorators, and creating a Stream object that handles signaling, connection management, and UI rendering. The codebase is actively maintained with frequent commits and an extensive set of demos integrating with various LLMs and AI services.