apache/solr

Project overview

Apache Solr is an open-source search platform built on Apache Lucene. It provides full-text, vector, and geospatial search, and is maintained by the Apache Software Foundation under the Apache-2.0 license. The repo targets Java developers and operators who need to build and run a search service: indexing data, querying collections, and managing deployments.

Solr ships as a server distribution. You start it with the bin/solr script, create collections, and index documents through HTTP APIs or bundled tools. It can also run via the official Docker image or on Kubernetes through the Solr Operator.

Quick start

1. Download a Solr distribution from the downloads page, or use the official Docker image.
2. From the Solr distribution directory, start a bundled example:

bin/solr start -e techproducts

Available examples include cloud, techproducts, schemaless, and films (README). This starts Solr and loads sample data, so you can try queries immediately. 3. For a development build from source, use Gradle: run ./gradlew dev, then cd ./solr/packaging/build/dev and bin/solr start (README). 4. Open the admin UI at http://localhost:8983/solr/. Use the bin/solr post tool to index your own sample data.

For a guided walkthrough, see the Solr tutorial.

Usage constraints

• Runtime: Solr is a Java server application; the reference guide's deployment guide lists system requirements. Building from source requires Gradle and a compatible JDK.
• Deployment choices: Docker and Kubernetes setups are documented separately; the Operator is the official path for Kubernetes (Solr Operator).
• Scale: SolrCloud mode is the distributed deployment option; the cloud example demonstrates it, but a production cluster requires additional configuration.
• License: Apache-2.0 (license) imposes no usage restrictions beyond the standard terms.

HotRepo's take

Solr is an established search platform, not a newcomer. In the HotRepo GitHub daily ranking for the Java list on 2026-11-12, it held position 9 with 1,700 stars and no daily star gain, which fits a mature infrastructure project whose adoption is not reflected in star velocity. The repository was moved to the apache organization in 2021, yet the project's history and ecosystem are older. Readers evaluating it for a new search feature should focus on the operational model and query capabilities rather than this ranking, since one flat snapshot does not indicate trajectory.