Chainlit

Chainlit is an open-source Python framework that lets you build conversational AI applications in minutes. With 12k+ GitHub stars, it provides a complete frontend UI and API backend for chatbot interfaces, supporting LangChain, OpenAI, and any LLM backend. Chainlit makes it easy to prototype and deploy production-ready chatbot UIs with built-in support for streaming responses, multi-modal inputs (text, images, files), user session management, and authentication. Its Python-first approach means you can turn any LLM pipeline into an interactive chat interface with just a few lines of code.