Typesense

Typesense is a fast, typo-tolerant, in-memory search engine designed to be an open-source alternative to Algolia and a simpler alternative to Elasticsearch. It is purpose-built for building delightful, instant search experiences in websites and applications.

Typesense supports faceted search, geosearch, vector/semantic search, synonyms, curation, and multi-tenant indexing with a clean REST API. It can be self-hosted on your own infrastructure or used via Typesense Cloud, the managed hosted service. The in-memory architecture delivers sub-10ms query responses even on large datasets.

Its developer-friendly API and a JavaScript instant search adapter compatible with Algolia InstantSearch.js make it easy to migrate or add search to a new project. Typesense is written in C++ for maximum performance and is actively maintained with regular releases.