Some websites post lists the best of open source document search engines available, unfortunately, they don’t seem up to date or they don’t care about unmaintained projects. Here’s my updated list as of July 2023, in no particular order.
Note: there are some document management systems included because they also include a search feature.
Open Semantic Search
- https://github.com/opensemanticsearch/open-semantic-search
- Last update: March 2023
IResearch search engine
- https://github.com/iresearch-toolkit/iresearch
- Last update: June 2023
OpenSearch
- https://opensearch.org/
- Last update: July 2023
Meilisearch
- https://github.com/meilisearch/meilisearch
- Last update: July 2023
Teedy
- https://teedy.io/#!/
- Last update: June 2023
Papermerge
- https://papermerge.com/
- Last update: December 2022
Docassemble
- https://docassemble.org/
- Last update: July 2023
Elastic Enterprise Search
- https://www.elastic.co/enterprise-search
- Last update: July 2023
Note: I have not used nor tested all these solutions, this is just a list.