A curated list of 100+ libraries and frameworks for AI engineers building with LLMs
AI Engineering Toolkit🔥
Build better LLM apps — faster, smarter, production-ready.
A curated, list of 100+ libraries and frameworks for AI engineers building with Large Language Models. This toolkit includes battle-tested tools, frameworks, templates, and reference implementations for developing, deploying, and optimizing LLM-powered systems.


📋 Table of Contents
🛠️ Tooling for AI Engineers
Vector Databases
| Tool |
Description |
Language |
License |
| Pinecone |
Managed vector database for production AI applications |
API/SDK |
Commercial |
| Weaviate |
Open-source vector database with GraphQL API |
Go |
BSD-3 |
| Qdrant |
Vector similarity search engine with extended filtering |
Rust |
Apache-2.0 |
| Chroma |
Open-source embedding database for LLM apps |
Python |
Apache-2.0 |
| Milvus |
Cloud-native vector database for scalable similarity search |
Go/C++ |
Apache-2.0 |
| FAISS |
Library for efficient similarity search and clustering |
C++/Python |
MIT |
| Deep Lake |
AI-native data lake with versioned datasets, optimized for embeddings and multimodal storage |
Python |
Apache-2.0 |
| Vectara |
Managed RAG platform with APIs for retrieval and generation |
Python/Go |
Commercial |
Orchestration & Workflows
| Tool |
Description |
Language |
License |
| LangChain |
Framework for developing LLM applications |
Python/JS |
MIT |
| LlamaIndex |
Data framework for LLM applications |
Python |
MIT |
| Haystack |
End-to-end NLP framework for production |
Python |
Apache-2.0 |
| DSPy |
Framework for algorithmically optimizing LM prompts |
Python |
MIT |
| Semantic Kernel |
SDK for integrating AI into conventional programming languages |
C#/Python/Java |
MIT |
| Langflow |
Visual no-code platform for building and deploying LLM workflows |
Python/TypeScript |
MIT |
| Flowise |
Drag-and-drop UI for creating LLM chains and agents |
TypeScript |
MIT |
| Promptflow |
Workflow orchestration for LLM pipelines, evaluation, and deployment |
Python |
MIT |
| Dify |
Production-ready open source platform combining RAG pipelines, agent capabilities, model management, and observability in one UI |
TypeScript/Python |
Apache-2.0 |
PDF Extraction Tools
| Tool |
Description |
Language |
License |
| Docling |
AI-powered toolkit converting PDF, DOCX, PPTX, HTML, images into structured JSON/Markdown with layout, OCR, table, and code recognition |
Python |
MIT |
| pdfplumber |
Drill through PDFs at a character level, extract text & tables, and visually debug extraction |
Python |
MIT |
| PyMuPDF (fitz) |
Lightweight, high-performance PDF parser for text/image extraction and manipulation |
Python / C |
AGPL-3.0 |
| PDF.js |
Browser-based PDF renderer with text extraction capabilities |
JavaScript |
Apache-2.0 |
| Camelot |
Extracts structured tabular data from PDFs into DataFrames and CSVs |
Python |
MIT |
| Unstructured |
Parse PDFs, DOCX, HTML into structured JSON for LLM workflows |
Python |
Apache-2.0 |
| pdfminer.six |
Detailed PDF text extraction and layout analysis |
Python |
MIT |
| Llama Parse |
Structured parsing of PDFs and documents optimized for LLMs |
Python |
Apache-2.0 |
| MegaParse |
Universal parser for PDFs, HTML, and semi-structured documents |
Python |
Apache-2.0 |
| ExtractThinker |
Intelligent document extraction framework with schema mapping |
Python |
MIT |
| PyMuPDF4LLM |
Wrapper around PyMuPDF for LLM-ready text, tables, and image extraction |
Python |
Apache-2.0 |
RAG (Retrieval-Augmented Generation)
| Tool |
Description |
Language |
License |
| RAGFlow |
Open-source RAG engine based on deep document understanding |
Python |
Apache-2.0 |
| Verba |
Retrieval Augmented Generation (RAG) chatbot |
Python |
BSD-3 |
| PrivateGPT |
Interact with documents using local LLMs |
Python |
Apache-2.0 |
| AnythingLLM |
All-in-one AI application for any LLM |
JavaScript |
MIT |
| Quivr |
Your GenAI second brain |
Python/TypeScript |
Apache-2.0 |
| Jina |
Cloud-native neural search framework for multimodal RAG |
Python |
Apache-2.0 |
| txtai |
All-in-one embeddings database for semantic search and workflows |
Python |
Apache-2.0 |
| FastGraph RAG |
Graph-based RAG framework for structured retrieval |
Python |
MIT |
| Chonkie |
Chunking utility for efficient document processing in RAG |
Python |
- |
| FlashRAG |
Low-latency RAG research toolkit with modular design and benchmarks |
Python |
- |
| Llmware |
Lightweight framework for building RAG-based apps |
Python |
Apache-2.0 |
Evaluation & Testing
| Tool |
Description |
Language |
License |
| Evals |
OpenAI's framework for creating and running LLM evaluations |
Python |
MIT |
| Ragas |
Evaluation framework for RAG pipelines |
Python |
Apache-2.0 |
| Opik |
DevOps platform for evaluation, monitoring, and observability |
Python |
Apache-2.0 |
| Phoenix |
ML observability for LLM, vision, language, and tabular models |
Python |
Apache-2.0 |
| DeepEval |
LLM evaluation framework for unit testing LLM outputs |
Python |
Apache-2.0 |
| TruLens |
Evaluation and tracking for LLM experiments |
Python |
MIT |
| UpTrain |
Open-source tool to evaluate and improve LLM applications |
Python |
Apache-2.0 |
| Giskard |
Testing framework for ML/LLMs with bias and robustness checks |
Python |
Apache-2.0 |
| Weave |
Experiment tracking, debugging, and logging for LLM workflows |
Python |
Apache-2.0 |
| Lighteval |
Lightweight and fast evaluation framework from Hugging Face |
Python |
Apache-2.0 |
| Langfuse |
Open source LLM engineering platform with tracing, evals, prompt management, and metrics |
TypeScript/Python |
MIT |
| Helicone |
Open source observability and monitoring platform for debugging and improving LLM apps |
TypeScript |
Apache-2.0 |
| OpenLLMetry |
OpenTelemetry-based observability extensions for LLM apps — plugs into Datadog, Honeycomb, and more |
Python |
Apache-2.0 |
Model Management
| Tool |
Description |
Language |
License |
| Hugging Face Hub |
Client library for Hugging Face Hub |
Python |
Apache-2.0 |
| MLflow |
Platform for ML lifecycle management |
Python |
Apache-2.0 |
| Weights & Biases |
Developer tools for ML |
Python |
MIT |
| DVC |
Data version control for ML projects |
Python |
Apache-2.0 |
| ClearML |
End-to-end MLOps platform with LLM support |
Python |
Apache-2.0 |
Data Collection & Web Scraping
| Tool |
Description |
Language |
License |
| Firecrawl |
AI-powered web crawler that extracts and structures content for LLM pipelines |
TypeScript |
MIT |
| Scrapy |
Fast, high-level web crawling & scraping framework |
Python |
BSD-3 |
| Playwright |
Web automation & scraping with headless browsers |
TypeScript/Python/Java/.NET |
Apache-2.0 |
| BeautifulSoup |
Easy HTML/XML parsing for quick scraping tasks |
Python |
MIT |
| Selenium |
Browser automation framework (supports scraping) |
Multiple |
Apache-2.0 |
| Newspaper3k |
News & article extraction library |
Python |
MIT |
| Crawl4AI |
Fast, lightweight, and modern web crawling & scraping library for AI data pipelines |
Python |
Apache-2.0 |
| Colly |
High-performance scraping framework for Go |
Go |
BSD-2 |
| Trafilatura |
Extract clean text from web pages for LLM training corpora |
Python |
MIT |
| ScrapeGraphAI |
Use LLMs to extract structured data from websites and documents |
Python |
MIT |
| Crawlee |
Web scraping and crawling framework for large-scale data collection |
TypeScript |
Apache-2.0 |
🤖 Agent Frameworks
| Framework |
Description |
Language |
License |
| Google's ADK |
Flexible and modular framework for developing and deploying AI agents |
Python / Java |
Apache-2.0 |
| AutoGen |
Multi-agent conversation framework |
Python |
CC-BY-4.0 |
| CrewAI |
Framework for orchestrating role-playing autonomous AI agents |
Python |
MIT |
| LangGraph |
Build resilient language agents as graphs |
Python |
MIT |
| AgentOps |
Python SDK for AI agent monitoring, LLM cost tracking, benchmarking |
Python |
MIT |
| Swarm |
Educational framework for exploring ergonomic, lightweight multi-agent orchestration |
Python |
MIT |
| Agency Swarm |
An open-source agent framework designed to automate your workflows |
Python |
MIT |
| Multi-Agent Systems |
Research into multi-agent systems and applications |
Python |
MIT |
| Auto-GPT |
Autonomous AI agent for task execution using GPT models |
Python |
MIT |
| BabyAGI |
Task-driven autonomous agent inspired by AGI |
Python |
MIT |
| SuperAGI |
Infrastructure for building and managing autonomous agents |
Python |
MIT |
| Griptape |
Framework for building AI agents with structured pipelines and memory |
Python |
Apache-2.0 |
| Letta (MemGPT) |
Long-term memory management for LLM agents |
Python |
MIT |
| Agno |
Framework for building AI agents with RAG, workflows, and memory |
Python |
Apache-2.0 |
| Agents SDK |
SDK from Vercel for building agentic workflows and applications |
TypeScript |
Apache-2.0 |
| Smolagents |
Lightweight agent framework from Hugging Face |
Python |
Apache-2.0 |
| Pydantic AI |
Agent framework built on Pydantic for structured reasoning |
Python |
MIT |
| CAMEL |
Multi-agent framework enabling role-play and collaboration |
Python |
Apache-2.0 |
| Swarms |
Enterprise agent orchestration framework (“Agency Swarm”) |
Python |
MIT |
| Langroid |
Framework for building multi-agent conversational systems |
Python |
Apache-2.0 |
| Upsonic |
Agent framework focused on context management and tool use |
Python |
Apache-2.0 |
| Mem0 |
Universal memory layer for AI agents — persistent, personalized memory across sessions |
Python |
Apache-2.0 |
📦 LLM Development & Optimization
LLM Training and Fine-Tuning
| Tool |
Description |
Language |
License |
| PyTorch Lightning |
High-level PyTorch interface for LLMs |
Python |
Apache-2.0 |
| unsloth |
Fine-tune LLMs faster with less memory |
Python |
Apache-2.0 |
| Axolotl |
Post-training pipeline for AI models |
Python |
Apache-2.0 |
| LLaMA-Factory |
Easy & efficient LLM fine-tuning |
Python |
Apache-2.0 |
| PEFT |
Parameter-Efficient Fine-Tuning library |
Python |
Apache-2.0 |
| DeepSpeed |
Distributed training & inference optimization |
Python |
MIT |
| TRL |
Train transformer LMs with reinforcement learning |
Python |
Apache-2.0 |
| Transformers |
Pretrained models for text, vision, and audio tasks |
Python |
Apache-2.0 |
| LitGPT |
Train and fine-tune LLMs lightning fast |
Python |
Apache-2.0 |
| Ludwig |
Low-code framework for custom LLMs |
Python |
Apache-2.0 |
| xTuring |
Fast fine-tuning of open-source LLMs |
Python |
Apache-2.0 |
| RL4LMs |
RL library to fine-tune LMs to human preferences |
Python |
Apache-2.0 |
| torchtune |
PyTorch-native library for fine-tuning LLMs |
Python |
BSD-3 |
| Accelerate |
Library to easily train on multiple GPUs/TPUs with mixed precision |
Python |
Apache-2.0 |
Open Source LLM Inference
| Tool |
Description |
Language |
License |
| LLM Compressor |
Transformers-compatible library for applying various compression algorithms to LLMs for optimized deployment |
Python |
Apache-2.0 |
| LightLLM |
Lightweight Python-based LLM inference and serving framework with easy scalability and high performance |
Python |
Apache-2.0 |
| vLLM |
High-throughput and memory-efficient inference and serving engine for LLMs |
Python |
Apache-2.0 |
| TensorRT-LLM |
NVIDIA library for optimizing LLM inference with TensorRT |
C++/Python |
Apache-2.0 |
| WebLLM |
High-performance in-browser LLM inference engine |
TypeScript/Python |
Apache-2.0 |
| SkyPilot |
Unified framework to run ML workloads and LLMs on any cloud (AWS, GCP, Azure, Lambda, etc.) with auto-spot, data syncing, and cost optimization. |
Python |
Apache-2.0 |
LLM Safety and Security
| Tool |
Description |
Language |
License |
| Guardrails |
Add guardrails to large language models |
Python |
MIT |
| NeMo Guardrails |
Toolkit for adding programmable guardrails to LLM conversational systems |
Python |
Apache-2.0 |
| Garak |
LLM vulnerability scanner |
Python |
MIT |
| DeepTeam |
LLM red teaming framework |
Python |
Apache-2.0 |
AI App Development Frameworks
| Tool |
Description |
Language |
License |
| Reflex |
Build full-stack web apps powered by LLMs with Python-only workflows and reactive UIs. |
Python |
Apache-2.0 |
| Gradio |
Create quick, interactive UIs for LLM demos and prototypes. |
Python |
Apache-2.0 |
| Streamlit |
Build and share AI/ML apps fast with Python scripts and interactive widgets. |
Python |
Apache-2.0 |
| Taipy |
End-to-end Python framework for building production-ready AI apps with dashboards and pipelines. |
Python |
Apache-2.0 |
| AI SDK UI |
Vercel’s AI SDK for building chat & generative UIs |
TypeScript |
Apache-2.0 |
| Simpleaichat |
Minimal Python interface for prototyping conversational LLMs |
Python |
MIT |
| Chainlit |
Framework for building and debugging LLM apps with a rich UI |
Python |
Apache-2.0 |
| Mirascope |
Lightweight Python toolkit for building LLM apps with Pydantic-native structured outputs and no extra abstractions |
Python |
MIT |
Local Development & Serving
| Tool |
Description |
Language |
License |
| Ollama |
Get up and running with large language models locally |
Go |
MIT |
| LM Studio |
Desktop app for running local LLMs |
- |
Commercial |
| GPT4All |
Open-source chatbot ecosystem |
C++ |
MIT |
| LocalAI |
Self-hosted OpenAI-compatible API |
Go |
MIT |
| llama.cpp |
Lightweight, high-performance inference engine for running LLMs locally across CPU, GPU, and mobile backends |
C++ |
MIT |
| LiteLLM |
Lightweight OpenAI-compatible gateway for multiple LLM providers |
Python |
MIT |
| AI Gateway |
Gateway for managing LLM requests, caching, and routing |
Python |
Apache-2.0 |
| Langcorn |
Serve LangChain applications via FastAPI with production-ready endpoints |
Python |
MIT |
| LitServe |
High-speed GPU inference server with autoscaling and batch support |
Python |
Apache-2.0 |
Structured Generation
| Tool |
Description |
Language |
License |
| Instructor |
Multi-language library for extracting structured, validated outputs from LLMs using Pydantic |
Python/TS/Go |
MIT |
| Outlines |
Guarantees 100% valid structured outputs (JSON, regex, grammars) by constraining LLM token generation |
Python |
Apache-2.0 |
| Guidance |
Microsoft's language for controlling LLM outputs — interleave generation with conditionals, loops, and constraints |
Python |
MIT |
LLM Inference Platforms
| Platform |
Description |
Pricing |
Features |
| Clarifai |
Lightning-fast compute for AI models & agents |
Free tier + Pay-as-you-go |
Pre-trained models, Deploy your own models on Dedicated compute, Model training, Workflow automation |
| Modal |
Serverless platform for AI/ML workloads |
Pay-per-use |
Serverless GPU, Auto-scaling |
| Replicate |
Run open-source models with a cloud API |
Pay-per-use |
Pre-built models, Custom training |
| Together AI |
Cloud platform for open-source models |
Various |
Open models, Fine-tuning |
| Anyscale |
Ray-based platform for AI applications |
Enterprise |
Distributed training, Serving |
| Groq |
Ultra-fast LPU inference engine for running open AI models |
Free tier + Pay-per-use |
Blazing fast speed, High throughput, Low latency, Open model support |
| OpenRouter |
Universal API to find and route to the best LLMs from various providers |
Free tier + Pay-per-use |
Multi-provider access, Unified API, Model comparison, Caching |
| RouteLLM |
Dynamic router for selecting best LLMs based on cost & performance |
Open-source |
Cost optimization, Multi-LLM routing |
🤝 Contributing
We welcome contributions! This toolkit grows stronger with community input.
How to Contribute
- Fork the repository
- Create a feature branch (
git checkout -b feature/amazing-tool)
- Add your contribution (new tool, template, or tutorial)
- Submit a pull request
Contribution Guidelines
- Quality over quantity - Focus on tools and resources that provide real value
- Production-ready - Include tools that work in real-world scenarios
- Well-documented - Provide clear descriptions and usage examples
- Up-to-date - Ensure tools are actively maintained
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