Algolia - Algolia's Search API makes it easy to deliver a great search experience in your apps & websites. Algolia Search provides hosted full-text, numerical, faceted and geolocalized search.
INDIE LMS - INDIE is an LMS for entrepreneurs that makes it easy to create, manage, and sell online courses
ElasticSearch - Elasticsearch is an open source, distributed, RESTful search engine.
Brilliant.org - Brilliant - Understand concepts and build your problem solving skills with thousands of free problems and examples in math, science, and engineering.
Site Search 360 - Site Search 360 enhances and improves your built-in CMS or product search with autocompletion, semantic search, filters, facets, detailed analytics, and a whole lot of customization options.
Math Doubts - Math Doubts is a scientific mathematics learning places, targets students, teachers and...