Meilisearch is a lightning-fast search engine API for apps and websites, offering typo-tolerant full-text search plus vector and AI-ready hybrid retrieval.
59.1k stars2.7k forkslast commit Actively maintained
11 self-hosted IBM Watson Discovery alternatives
AI-powered enterprise search and content analytics service that ingests, enriches and indexes unstructured documents to enable semantic search, question answering, entity extraction and insight discovery across business content.
Alternatives to IBM Watson Discovery
Open-source platform for AI chat, RAG, agents, and enterprise search across your team’s connected knowledge sources, compatible with hosted and local LLMs.
31.8k stars4.4k forkslast commit Actively maintained
Typesense is a developer-friendly search engine for instant, typo-tolerant search-as-you-type with faceting, filtering, geo search, and vector/semantic search APIs.
26.5k stars965 forksGPL-3.0last commit Actively maintained
OpenSearch is an Apache 2.0 open source distributed search and analytics engine for indexing, querying, and analyzing large-scale data with REST APIs.
13.6k stars2.9k forksApache-2.0last commit Actively maintained
Manticore Search is a fast open-source search database for full-text, faceted, and vector search with SQL (MySQL protocol) and HTTP JSON APIs.
12k stars641 forksGPL-3.0last commit Actively maintained
Extension for Paperless‑ngx that uses OpenAI-compatible backends and Ollama to auto-classify, tag, index, and enable RAG-powered document chat and semantic search.
5.9k stars327 forksMITlast commit Actively maintained
#7
YaCy is a self-hostable search engine with crawler and indexing, supporting decentralized P2P search, standalone search portals, and intranet/file search.
4k stars495 forkslast commit Actively maintained
#8
Aleph indexes documents and structured datasets to enable fast search, entity extraction, and cross-referencing for investigative research and OSINT workflows.
2.4k stars358 forksMITlast commit Slowing down
Scalable enterprise search platform supporting full-text, vector, faceted and geospatial search with SolrCloud clustering and a web admin UI.
1.7k stars859 forksApache-2.0last commit Actively maintained
#10
Fess is an open-source enterprise search server with a built-in crawler, web-based administration, and OpenSearch/Elasticsearch-backed full-text search.
1.1k stars175 forksApache-2.0last commit Actively maintained
#11
Web application to manage, annotate, and share academic PDFs with full-text search, OCR, citation import, and team collaboration.
347 stars32 forksGPL-3.0last commit Slowing down
What replacing IBM Watson Discovery actually involves
Every option on this page is open source and free to run on your own hardware, so you own the data and there is no subscription to cancel. 9 of 11 shipped a commit in the last six months. Licences in this list: GPL-3.0, Apache-2.0, MIT. In exchange you take on hosting, backups and updates yourself.
Browse everything in Search & Indexing Engines.
