Fess
Fess is a very powerful and easily deployable Enterprise Search Server.
Hound
Lightning fast code searching made easy.
Jina
Cloud-native neural search framework for any kind of data.
LibreX
Framework and javascript free privacy respecting meta search engine.
Manticore Search
Full-text search and data analytics, with fast response time for small, medium and big data (alternative to Elasticsearch).
MeiliSearch
Ultra relevant, instant and typo-tolerant full-text search API.
OpenSearch
Open source distributed and RESTful search engine.
SearXNG
Internet metasearch engine which aggregates results from various search services and databases (Fork of Searx).
sist2
Lightning-fast file system indexer and search tool.
Sosse
Selenium based search engine and crawler with offline archiving.
Typesense
Blazing fast, typo-tolerant open source search engine optimized for developer happiness and ease of use.
Websurfx
Aggregate results from other search engines (metasearch engine) without ads while keeping privacy and security in mind. It is extremely fast and provides a high level of customization (alternative to SearX).
Whoogle
A self-hosted, ad-free, privacy-respecting metasearch engine.
Yacy
Peer based, decentralized search engine server.
ZincSearch
Search engine that requires minimal resources (alternative to Elasticsearch).