Apache Solr

Apache Solr is an open source, multi-modal search platform built on Apache Lucene. It powers full-text, vector, and geospatial search at scale, and is built for organizations that index and query very large collections of data.

Solr runs as its own server, with a browser admin console and a bin/solr command-line tool for creating and managing collections and indexing data. Built-in examples cover SolrCloud, schemaless indexing, and dynamic fields, so a working instance comes up in minutes.

It ships an official Docker image and has first-class Kubernetes support through the Solr Operator, with downloads and full distributions available for self-hosted deployments. Solr is maintained at the Apache Software Foundation.