tntsearch - A fully featured full text search engine written in PHP

•    PHP

We created also some demo pages that show tolerant retrieval with n-grams in action. The package has bunch of helper functions like jaro-winkler and cosine similarity for distance calculations. It supports stemming for English, Croatian, Arabic, Italian, Russian, Portuguese and Ukrainian. If the built in stemmers aren't enough, the engine lets you easily plugin any compatible snowball stemmer. Some forks of the package even support Chinese. Unlike many other engines, the index can be easily updated without doing a reindex or using deltas.

RediSearch - FullText Search module for redis

•    C

Redisearch implements a search engine on top of Redis, but unlike other redis search libraries, it does not use internal data structures like sorted sets. Inverted indexes are stored as a special compressed data type that allows for fast indexing and search speed, and low memory footprint.

cassandra-lucene-index - Lucene based secondary indexes for Cassandra

•    Java

Cassandra Lucene index

NoSQL aspects db

Orthogonal provides the ability to index and search any type of data, including via fulltext and can search through the definition of cross-cutting aspects.

elastics - simple elasticsearch client for node.js

•    CoffeeScript

Simple & handy client for elasticsearch

mongoose-fulltext - Fulltext search plugin for mongoose & mongodb

•    Javascript

Dead simple fulltext search plugin for mongoose & mongodb. Supports term-frequency based scoring and stopwords.

fts - Fast fuzzy unicode-aware full-text-search engine for node.js

•    CoffeeScript

I had enough with all the search modules out there not having a hint of international characters support in their implementation so I decided to just write one. If atleast to get other module authors to pay more attention to people who don't speak English as their native language. As I'm just using this for a few of my low-traffic personal side projects, I will definitely need your help to submit enhancements and fix whatever bugs you may find.

nroonga - A library for building Groonga powered nodes

•    C++

nroonga is a library for building groonga powered nodes. You can write your custom full-text search backend on the top of node.js and groonga. NOTE: You need to install libgroonga-dev package in order to install nroonga.

full-text-rss - Full-Text RSS can transform partial feeds to deliver the full content stripped of clutter and ads

•    PHP

This is a our public version of Full-Text RSS available to download for free from http://code.fivefilters.org. For best extraction results, and to help us sustain the project, you can purchase the most up-to-date version at http://fivefilters.org/content-only/#download - so if you like this free version, please consider supporting us by purchasing the latest release.

node-fulltext - Fulltext search engine for node.js

•    Javascript

Add text to a fulltext database. Update item in a fulltext database.

ckanext-extractor - A full text and metadata extractor for CKAN

•    Python

A CKAN extension for automatically extracting text and metadata from datasets. ckanext-extractor automatically extracts text and metadata from your resources and adds them to the search index so that they can be used to find your data.