Top RETRIEVAL GitHub Repositories & Tools (2026)

Long-term memory runtime for AI agents — plain Markdown as the source of truth, local ranked retrieval, and an independent sleep-time Manage layer. Claude Code and Codex share one store. No API key.

[EMNLP2025] LightRAG: Simple and Fast Retrieval-Augmented Generation

RAGFlow is a leading open-source Retrieval-Augmented Generation (RAG) engine that fuses cutting-edge RAG with Agent capabilities to create a superior context layer for LLMs

The ultimate RAG for your monorepo. Query, understand, and edit multi-language codebases with the power of AI and knowledge graphs

Open-source inference server and production cluster for all the models your agent needs.

PipesHub is an open-source platform for securely connecting enterprise knowledge to AI. Give AI agents trusted context and your team permission-aware search with verified citations across your business systems.

AI pair programming in your terminal — one static binary, sub-ms startup, any model

Ready-to-run cloud templates for RAG, AI pipelines, and enterprise search with live data. 🐳Docker-friendly.⚡Always in sync with Sharepoint, Google Drive, S3, Kafka, PostgreSQL, real-time data APIs, and more.

Apache Lucene open-source search software

Apache Lucene.NET is an open-source full-text search library written in C#, ported from the Apache Lucene project.

Apache Solr open-source search software

Find code by asking what it does. A CLI for coding agents that uses Jev to discover relevant files and source context.

A Fork of Rikkahub with an overhauled UI and feature additions

Improve your OpenSearch, Elasticsearch, Solr, Vectara, Algolia and Custom Search search quality.

Long-term memory for Hermes and Codex, with local storage, source-backed recall, and tools to inspect, correct, or delete remembered information.

A queryable second brain over your scattered notes and docs - hybrid retrieval (vector + BM25), section-level citations, and an MCP server so AI agents can use it. ~300 lines, no LangChain.

Fast and Accurate Code Search for Agents. Uses 99% fewer tokens than grep+read

[MLsys2026 Best Paper]: https://arxiv.org/abs/2506.08276. RAG on Everything with LEANN. Enjoy 97% storage savings while running a fast, accurate, and 100% private RAG application on your personal device.