App Frameworks

Libraries for building LLM-powered applications

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Hugging Face Transformers

⭐ 165.2k

The definitive library for working with pre-trained transformer models.

intermediate

modelspythonhuggingface

Dify

⭐ 155.6k

Open-source platform for building LLM apps with a visual workflow editor.

beginner

low-codeworkflowrag

LangChain

⭐ 146.2k

The most popular LLM app framework with the largest ecosystem.

beginner

ragagentschains

AutoGen

⭐ 61.0k

Microsoft's multi-agent conversation framework for building complex LLM workflows.

intermediate

multi-agentmicrosoftconversation

LiteLLM

⭐ 58.6k

Universal API proxy that provides a unified OpenAI-compatible interface to 100+ LLM providers.

beginner

proxygatewayopenai-compatible

CrewAI

⭐ 58.4k

Multi-agent orchestration framework with role-based agent design.

intermediate

agentsmulti-agentorchestration

LlamaIndex

⭐ 52.1k

Purpose-built for RAG and data retrieval pipelines.

beginner

ragindexingpython

LangGraph

⭐ 41.5k

Framework for building stateful, multi-step agent workflows as graphs.

intermediate

agentsstate-machinegraph

OpenAI Agents SDK

⭐ 29.4k

OpenAI's official framework for building multi-agent workflows with handoffs and guardrails.

intermediate

agentsopenaipython

Semantic Kernel

⭐ 28.6k

Microsoft's lightweight SDK for integrating LLMs into conventional applications.

intermediate

microsoftenterprisecsharp

Vercel AI SDK

⭐ 26.7k

The go-to TypeScript toolkit for building AI-powered web apps with streaming UI.

beginner

typescriptstreamingreact

Haystack

⭐ 26.5k

Production-ready framework for building LLM applications with composable pipelines.

intermediate

ragpipelinespython

OpenRouter

⭐ 1.3k

Unified API gateway providing access to hundreds of models from multiple providers.

beginner

api-gatewaymulti-modelrouting

All Projects

• AutoGen — Microsoft's multi-agent conversation framework for building complex LLM workflows.
• CrewAI — Multi-agent orchestration framework with role-based agent design.
• Dify — Open-source platform for building LLM apps with a visual workflow editor.
• Haystack — Production-ready framework for building LLM applications with composable pipelines.
• LangChain — The most popular LLM app framework with the largest ecosystem.
• LangGraph — Framework for building stateful, multi-step agent workflows as graphs.
• LiteLLM — Universal API proxy that provides a unified OpenAI-compatible interface to 100+ LLM providers.
• LlamaIndex — Purpose-built for RAG and data retrieval pipelines.
• OpenAI Agents SDK — OpenAI's official framework for building multi-agent workflows with handoffs and guardrails.
• OpenRouter — Unified API gateway providing access to hundreds of models from multiple providers.
• Semantic Kernel — Microsoft's lightweight SDK for integrating LLMs into conventional applications.
• Hugging Face Transformers — The definitive library for working with pre-trained transformer models.
• Vercel AI SDK — The go-to TypeScript toolkit for building AI-powered web apps with streaming UI.