The project's README from github.com/KalyanKS-NLP/llm-engineer-toolkit. As one markdown file: README.md.
This repository contains a curated list of 120+ LLM libraries category wise.
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| Library | Description | Link |
|---|---|---|
| unsloth | Fine-tune LLMs faster with less memory. | Link |
| PEFT | State-of-the-art Parameter-Efficient Fine-Tuning library. | Link |
| TRL | Train transformer language models with reinforcement learning. | Link |
| Transformers | Transformers provides thousands of pretrained models to perform tasks on different modalities such as text, vision, and audio. | Link |
| Axolotl | Tool designed to streamline post-training for various AI models. | Link |
| LLMBox | A comprehensive library for implementing LLMs, including a unified training pipeline and comprehensive model evaluation. | Link |
| LitGPT | Train and fine-tune LLM lightning fast. | Link |
| Mergoo | A library for easily merging multiple LLM experts, and efficiently train the merged LLM. | Link |
| Llama-Factory | Easy and efficient LLM fine-tuning. | Link |
| Ludwig | Low-code framework for building custom LLMs, neural networks, and other AI models. | Link |
| Txtinstruct | A framework for training instruction-tuned models. | Link |
| Lamini | An integrated LLM inference and tuning platform. | Link |
| XTuring | xTuring provides fast, efficient and simple fine-tuning of open-source LLMs, such as Mistral, LLaMA, GPT-J, and more. | Link |
| RL4LMs | A modular RL library to fine-tune language models to human preferences. | Link |
| DeepSpeed | DeepSpeed is a deep learning optimization library that makes distributed training and inference easy, efficient, and effective. | Link |
| torchtune | A PyTorch-native library specifically designed for fine-tuning LLMs. | Link |
| PyTorch Lightning | A library that offers a high-level interface for pretraining and fine-tuning LLMs. | Link |
| RapidFire AI | Rapid AI experimentation framework for fine-tuning and post-training LLMs (SFT, DPO, GRPO) with hyperparallelized execution and real-time interactive control. | Link |
Frameworks
| Library | Description | Link |
|---|---|---|
| LangChain | LangChain is a framework for developing applications powered by large language models (LLMs). | Link |
| Llama Index | LlamaIndex is a data framework for your LLM applications. | Link |
| HayStack | Haystack is an end-to-end LLM framework that allows you to build applications powered by LLMs, Transformer models, vector search and more. | Link |
| Prompt flow | A suite of development tools designed to streamline the end-to-end development cycle of LLM-based AI applications. | Link |
| Griptape | A modular Python framework for building AI-powered applications. | Link |
| Weave | Weave is a toolkit for developing Generative AI applications. | Link |
| Llama Stack | Build Llama Apps. | Link |
Data Preparation
| Library | Description | Link |
|---|---|---|
| Data Prep Kit | Data Prep Kit accelerates unstructured data preparation for LLM app developers. Developers can use Data Prep Kit to cleanse, transform, and enrich use case-specific unstructured data to pre-train LLMs, fine-tune LLMs, instruct-tune LLMs, or build RAG applications. | Link |
Multi API Access
| Library | Description | Link |
|---|---|---|
| LiteLLM | Library to call 100+ LLM APIs in OpenAI format. | Link |
| AI Gateway | A Blazing Fast AI Gateway with integrated Guardrails. Route to 200+ LLMs, 50+ AI Guardrails with 1 fast & friendly API. | Link |
| Bifrost | High-performance AI gateway with a unified OpenAI-compatible API, multi-provider routing, automatic fallbacks, load balancing, and observability. | Link |
Routers
| Library | Description | Link |
|---|---|---|
| OpenRoutiQ | Explainable, policy-controlled Python router for selecting models, providers, deployments, and reasoning levels, with optional outcome learning and an OpenAI-compatible proxy. | Link |
| RouteLLM | Framework for serving and evaluating LLM routers - save LLM costs without compromising quality. Drop-in replacement for OpenAI's client to route simpler queries to cheaper models. | Link |
Memory
| Library | Description | Link |
|---|---|---|
| mem0 | The Memory layer for your AI apps. | Link |
| Memoripy | An AI memory layer with short- and long-term storage, semantic clustering, and optional memory decay for context-aware applications. | Link |
| Tree Ring Memory | Local-first memory lifecycle for AI agents with Rust CLI/TUI, SQLite/FTS recall, audit, consolidation, and forgetting. | Link |
| Letta (MemGPT) | An open-source framework for building stateful LLM applications with advanced reasoning capabilities and transparent long-term memory | Link |
| Memobase | A user profile-based memory system designed to bring long-term user memory to your Generative AI applications. | Link |
Interface
| Library | Description | Link |
|---|---|---|
| Streamlit | A faster way to build and share data apps. Streamlit lets you transform Python scripts into interactive web apps in minutes | Link |
| Gradio | Build and share delightful machine learning apps, all in Python. | Link |
| AI SDK UI | Build chat and generative user interfaces. | Link |
| AI-Gradio | Create AI apps powered by various AI providers. | Link |
| Simpleaichat | Python package for easily interfacing with chat apps, with robust features and minimal code complexity. | Link |
| Chainlit | Build production-ready Conversational AI applications in minutes. | Link |
Low Code
| Library | Description | Link |
|---|---|---|
| LangFlow | LangFlow is a low-code app builder for RAG and multi-agent AI applications. It’s Python-based and agnostic to any model, API, or database. | Link |
Cache
| Library | Description | Link |
|---|---|---|
| GPTCache | A Library for Creating Semantic Cache for LLM Queries. Slash Your LLM API Costs by 10x 💰, Boost Speed by 100x. Fully integrated with LangChain and LlamaIndex. | Link |
| Library | Description | Link |
|---|---|---|
| FastGraph RAG | Streamlined and promptable Fast GraphRAG framework designed for interpretable, high-precision, agent-driven retrieval workflows. | Link |
| Chonkie | RAG chunking library that is lightweight, lightning-fast, and easy to use. | Link |
| RAGChecker | A Fine-grained Framework For Diagnosing RAG. | Link |
| RAG to Riches | Build, scale, and deploy state-of-the-art Retrieval-Augmented Generation applications. | Link |
| BeyondLLM | Beyond LLM offers an all-in-one toolkit for experimentation, evaluation, and deployment of Retrieval-Augmented Generation (RAG) systems. | Link |
| SQLite-Vec | A vector search SQLite extension that runs anywhere! | Link |
| fastRAG | fastRAG is a research framework for efficient and optimized retrieval-augmented generative pipelines, incorporating state-of-the-art LLMs and Information Retrieval. | Link |
| FlashRAG | A Python Toolkit for Efficient RAG Research. | Link |
| Llmware | Unified framework for building enterprise RAG pipelines with small, specialized models. | Link |
| Rerankers | A lightweight unified API for various reranking models. | Link |
| Vectara | Build Agentic RAG applications. | Link |
| RapidFire AI | Rapid AI experimentation framework for RAG and context engineering with hyperparallelized, shard-based execution and real-time interactive control. | Link |
| Library | Description | Link |
|---|---|---|
| llama.cpp | LLM inference in C/C++. | Link |
| Ollama | Local LLM inference. | Link |
| vLLM | High-throughput and memory-efficient inference and serving engine for LLMs. | Link |
| TensorRT-LLM | TensorRT-LLM is a library for optimizing Large Language Model (LLM) inference. | Link |
| WebLLM | High-performance In-browser LLM Inference Engine. | Link |
| LLM Compressor | Transformers-compatible library for applying various compression algorithms to LLMs for optimized deployment. | Link |
| LightLLM | Python-based LLM inference and serving framework, notable for its lightweight design, easy scalability, and high-speed performance. | Link |
| torchchat | Run PyTorch LLMs locally on servers, desktop, and mobile. | Link |
| Library | Description | Link |
|---|---|---|
| Langcorn | Serving LangChain LLM apps and agents automagically with FastAPI. | Link |
| LitServe | Lightning-fast serving engine for any AI model of any size. It augments FastAPI with features like batching, streaming, and GPU autoscaling. | Link |
| Library | Description | Link |
|---|---|---|
| Crawl4AI | Open-source LLM Friendly Web Crawler & Scraper. | Link |
| ScrapeGraphAI | A web scraping Python library that uses LLM and direct graph logic to create scraping pipelines for websites and local documents (XML, HTML, JSON, Markdown, etc.). | Link |
| Docling | Docling parses documents and exports them to the desired format with ease |