Unspecified Search Engine References
- Ferret Text
- Gigablast by Matt Wells is a very old search engine from pre-database-engine era, when it was a very good and innovative thing, but as of 2018 it is an almost typical business-software project dirty hack that has had flaws/bugs accumulate for years to the point of rendering it unusable(local copy, FindX forking effort GitHub repository).
- Open Semantic
- The Lemur Project is an academic project.
- Yioop GPLv3 licensed PHP search engine
- Zettair Text Search Engine
The current list is very incomplete. It lacks the various Apache Lucene like software and the various file name search engines like Archie, locate, mlocate, etc.
Search Engine Components
- Apache Nutch web crawler
Links to Versioned File Collection
Closed Source P2P Search Engines
- 2015 book: Search Engines Information
Retrieval in Practice
- Z39.50 standard