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href="/docs/latest/configuration/"><span itemprop="name">Configuration</span></a><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="name">Extensions</span><meta itemprop="position" content="2"></li></ul></nav><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>Extensions</h1></header><p>Druid implements an extension system that allows for adding functionality at runtime. Extensions | 
 | are commonly used to add support for deep storages (like HDFS and S3), metadata stores (like MySQL | 
 | and PostgreSQL), new aggregators, new input formats, and so on.</p> | 
 | <p>Production clusters will generally use at least two extensions; one for deep storage and one for a | 
 | metadata store. Many clusters will also use additional extensions.</p> | 
 | <h2 class="anchor anchorWithStickyNavbar_LWe7" id="core-extensions">Core extensions<a href="#core-extensions" class="hash-link" aria-label="Direct link to Core extensions" title="Direct link to Core extensions"></a></h2> | 
 | <p>Core extensions are maintained by Druid committers.</p> | 
 | <table><thead><tr><th>Name</th><th>Description</th><th>Docs</th></tr></thead><tbody><tr><td>druid-avro-extensions</td><td>Support for data in Apache Avro data format.</td><td><a href="/docs/latest/development/extensions-core/avro">link</a></td></tr><tr><td>druid-azure-extensions</td><td>Microsoft Azure deep storage.</td><td><a href="/docs/latest/development/extensions-core/azure">link</a></td></tr><tr><td>druid-basic-security</td><td>Support for Basic HTTP authentication and role-based access control.</td><td><a href="/docs/latest/development/extensions-core/druid-basic-security">link</a></td></tr><tr><td>druid-bloom-filter</td><td>Support for providing Bloom filters in druid queries.</td><td><a href="/docs/latest/development/extensions-core/bloom-filter">link</a></td></tr><tr><td>druid-catalog</td><td>This extension allows users to configure, update, retrieve, and manage metadata stored in Druid's catalog.</td><td><a href="/docs/latest/development/extensions-core/catalog">link</a></td></tr><tr><td>druid-datasketches</td><td>Support for approximate counts and set operations with <a href="https://datasketches.apache.org/" target="_blank" rel="noopener noreferrer">Apache DataSketches</a>.</td><td><a href="/docs/latest/development/extensions-core/datasketches-extension">link</a></td></tr><tr><td>druid-google-extensions</td><td>Google Cloud Storage deep storage.</td><td><a href="/docs/latest/development/extensions-core/google">link</a></td></tr><tr><td>druid-hdfs-storage</td><td>HDFS deep storage.</td><td><a href="/docs/latest/development/extensions-core/hdfs">link</a></td></tr><tr><td>druid-histogram</td><td>Approximate histograms and quantiles aggregator. Deprecated, please use the <a href="/docs/latest/development/extensions-core/datasketches-quantiles">DataSketches quantiles aggregator</a> from the <code>druid-datasketches</code> extension instead.</td><td><a href="/docs/latest/development/extensions-core/approximate-histograms">link</a></td></tr><tr><td>druid-kafka-extraction-namespace</td><td>Apache Kafka-based namespaced lookup. Requires namespace lookup extension.</td><td><a href="/docs/latest/querying/kafka-extraction-namespace">link</a></td></tr><tr><td>druid-kafka-indexing-service</td><td>Supervised exactly-once Apache Kafka ingestion for the indexing service.</td><td><a href="/docs/latest/ingestion/kafka-ingestion">link</a></td></tr><tr><td>druid-kinesis-indexing-service</td><td>Supervised exactly-once Kinesis ingestion for the indexing service.</td><td><a href="/docs/latest/ingestion/kinesis-ingestion">link</a></td></tr><tr><td>druid-kerberos</td><td>Kerberos authentication for druid processes.</td><td><a href="/docs/latest/development/extensions-core/druid-kerberos">link</a></td></tr><tr><td>druid-lookups-cached-global</td><td>A module for <a href="/docs/latest/querying/lookups">lookups</a> providing a jvm-global eager caching for lookups. It provides JDBC and URI implementations for fetching lookup data.</td><td><a href="/docs/latest/querying/lookups-cached-global">link</a></td></tr><tr><td>druid-lookups-cached-single</td><td>Per lookup caching module to support the use cases where a lookup need to be isolated from the global pool of lookups</td><td><a href="/docs/latest/development/extensions-core/druid-lookups">link</a></td></tr><tr><td>druid-multi-stage-query</td><td>Support for the multi-stage query architecture for Apache Druid and the multi-stage query task engine.</td><td><a href="/docs/latest/multi-stage-query/">link</a></td></tr><tr><td>druid-orc-extensions</td><td>Support for data in Apache ORC data format.</td><td><a href="/docs/latest/development/extensions-core/orc">link</a></td></tr><tr><td>druid-parquet-extensions</td><td>Support for data in Apache Parquet data format. Requires druid-avro-extensions to be loaded.</td><td><a href="/docs/latest/development/extensions-core/parquet">link</a></td></tr><tr><td>druid-protobuf-extensions</td><td>Support for data in Protobuf data format.</td><td><a href="/docs/latest/development/extensions-core/protobuf">link</a></td></tr><tr><td>druid-s3-extensions</td><td>Interfacing with data in Amazon S3, and using S3 as deep storage.</td><td><a href="/docs/latest/development/extensions-core/s3">link</a></td></tr><tr><td>druid-ec2-extensions</td><td>Interfacing with AWS EC2 for autoscaling middle managers</td><td>UNDOCUMENTED</td></tr><tr><td>druid-aws-rds-extensions</td><td>Support for AWS token based access to AWS RDS DB Cluster.</td><td><a href="/docs/latest/development/extensions-core/druid-aws-rds">link</a></td></tr><tr><td>druid-stats</td><td>Statistics related module including variance and standard deviation.</td><td><a href="/docs/latest/development/extensions-core/stats">link</a></td></tr><tr><td>mysql-metadata-storage</td><td>MySQL metadata store.</td><td><a href="/docs/latest/development/extensions-core/mysql">link</a></td></tr><tr><td>postgresql-metadata-storage</td><td>PostgreSQL metadata store.</td><td><a href="/docs/latest/development/extensions-core/postgresql">link</a></td></tr><tr><td>simple-client-sslcontext</td><td>Simple SSLContext provider module to be used by Druid's internal HttpClient when talking to other Druid processes over HTTPS.</td><td><a href="/docs/latest/development/extensions-core/simple-client-sslcontext">link</a></td></tr><tr><td>druid-pac4j</td><td>OpenID Connect authentication for druid processes.</td><td><a href="/docs/latest/development/extensions-core/druid-pac4j">link</a></td></tr><tr><td>druid-kubernetes-extensions</td><td>Druid cluster deployment on Kubernetes without Zookeeper.</td><td><a href="/docs/latest/development/extensions-core/kubernetes">link</a></td></tr><tr><td>druid-kubernetes-overlord-extensions</td><td>Support for launching tasks in k8s without Middle Managers</td><td><a href="/docs/latest/development/extensions-core/k8s-jobs">link</a></td></tr></tbody></table> | 
 | <h2 class="anchor anchorWithStickyNavbar_LWe7" id="community-extensions">Community extensions<a href="#community-extensions" class="hash-link" aria-label="Direct link to Community extensions" title="Direct link to Community extensions"></a></h2> | 
 | <div class="theme-admonition theme-admonition-info admonition_xJq3 alert alert--info"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_BuS1"><p>Community extensions are not maintained by Druid committers, although we accept patches from community members using these extensions. They may not have been as extensively tested as the core extensions.</p></div></div> | 
 | <p>A number of community members have contributed their own extensions to Druid that are not packaged with the default Druid tarball. | 
 | If you'd like to take on maintenance for a community extension, please post on <a href="https://lists.apache.org/list.html?dev@druid.apache.org" target="_blank" rel="noopener noreferrer">dev@druid.apache.org</a> to let us know!</p> | 
 | <p>All of these community extensions can be downloaded using <a href="/docs/latest/operations/pull-deps">pull-deps</a> while specifying a <code>-c</code> coordinate option to pull <code>org.apache.druid.extensions.contrib:{EXTENSION_NAME}:{DRUID_VERSION}</code>.</p> | 
 | <table><thead><tr><th>Name</th><th>Description</th><th>Docs</th></tr></thead><tbody><tr><td>aliyun-oss-extensions</td><td>Aliyun OSS deep storage</td><td><a href="/docs/latest/development/extensions-contrib/aliyun-oss">link</a></td></tr><tr><td>ambari-metrics-emitter</td><td>Ambari Metrics Emitter</td><td><a href="/docs/latest/development/extensions-contrib/ambari-metrics-emitter">link</a></td></tr><tr><td>druid-cassandra-storage</td><td>Apache Cassandra deep storage.</td><td><a href="/docs/latest/development/extensions-contrib/cassandra">link</a></td></tr><tr><td>druid-cloudfiles-extensions</td><td>Rackspace Cloudfiles deep storage.</td><td><a href="/docs/latest/development/extensions-contrib/cloudfiles">link</a></td></tr><tr><td>druid-compressed-bigdecimal</td><td>Compressed Big Decimal Type</td><td><a href="/docs/latest/development/extensions-contrib/compressed-big-decimal">link</a></td></tr><tr><td>druid-ddsketch</td><td>Support for DDSketch approximate quantiles based on <a href="https://github.com/datadog/sketches-java" target="_blank" rel="noopener noreferrer">DDSketch</a></td><td><a href="/docs/latest/development/extensions-contrib/ddsketch-quantiles">link</a></td></tr><tr><td>druid-deltalake-extensions</td><td>Support for ingesting Delta Lake tables.</td><td><a href="/docs/latest/development/extensions-contrib/delta-lake">link</a></td></tr><tr><td>druid-distinctcount</td><td>DistinctCount aggregator</td><td><a href="/docs/latest/development/extensions-contrib/distinctcount">link</a></td></tr><tr><td>druid-iceberg-extensions</td><td>Support for ingesting Iceberg tables.</td><td><a href="/docs/latest/development/extensions-contrib/iceberg">link</a></td></tr><tr><td>druid-redis-cache</td><td>A cache implementation for Druid based on Redis.</td><td><a href="/docs/latest/development/extensions-contrib/redis-cache">link</a></td></tr><tr><td>druid-time-min-max</td><td>Min/Max aggregator for timestamp.</td><td><a href="/docs/latest/development/extensions-contrib/time-min-max">link</a></td></tr><tr><td>sqlserver-metadata-storage</td><td>Microsoft SQLServer metadata store.</td><td><a href="/docs/latest/development/extensions-contrib/sqlserver">link</a></td></tr><tr><td>graphite-emitter</td><td>Graphite metrics emitter</td><td><a href="/docs/latest/development/extensions-contrib/graphite">link</a></td></tr><tr><td>statsd-emitter</td><td>StatsD metrics emitter</td><td><a href="/docs/latest/development/extensions-contrib/statsd">link</a></td></tr><tr><td>kafka-emitter</td><td>Kafka metrics emitter</td><td><a href="/docs/latest/development/extensions-contrib/kafka-emitter">link</a></td></tr><tr><td>druid-thrift-extensions</td><td>Support thrift ingestion</td><td><a href="/docs/latest/development/extensions-contrib/thrift">link</a></td></tr><tr><td>druid-opentsdb-emitter</td><td>OpenTSDB metrics emitter</td><td><a href="/docs/latest/development/extensions-contrib/opentsdb-emitter">link</a></td></tr><tr><td>materialized-view-selection, materialized-view-maintenance</td><td>Materialized View</td><td><a href="/docs/latest/development/extensions-contrib/materialized-view">link</a></td></tr><tr><td>druid-moving-average-query</td><td>Support for <a href="https://en.wikipedia.org/wiki/Moving_average" target="_blank" rel="noopener noreferrer">Moving Average</a> and other Aggregate <a href="https://en.wikibooks.org/wiki/Structured_Query_Language/Window_functions" target="_blank" rel="noopener noreferrer">Window Functions</a> in Druid queries.</td><td><a href="/docs/latest/development/extensions-contrib/moving-average-query">link</a></td></tr><tr><td>druid-influxdb-emitter</td><td>InfluxDB metrics emitter</td><td><a href="/docs/latest/development/extensions-contrib/influxdb-emitter">link</a></td></tr><tr><td>druid-momentsketch</td><td>Support for approximate quantile queries using the <a href="https://github.com/stanford-futuredata/momentsketch" target="_blank" rel="noopener noreferrer">momentsketch</a> library</td><td><a href="/docs/latest/development/extensions-contrib/momentsketch-quantiles">link</a></td></tr><tr><td>druid-tdigestsketch</td><td>Support for approximate sketch aggregators based on <a href="https://github.com/tdunning/t-digest" target="_blank" rel="noopener noreferrer">T-Digest</a></td><td><a href="/docs/latest/development/extensions-contrib/tdigestsketch-quantiles">link</a></td></tr><tr><td>gce-extensions</td><td>GCE Extensions</td><td><a href="/docs/latest/development/extensions-contrib/gce-extensions">link</a></td></tr><tr><td>prometheus-emitter</td><td>Exposes <a href="/docs/latest/operations/metrics">Druid metrics</a> for <a href="https://prometheus.io/" target="_blank" rel="noopener noreferrer">Prometheus</a></td><td><a href="/docs/latest/development/extensions-contrib/prometheus">link</a></td></tr><tr><td>druid-spectator-histogram</td><td>Support for efficient approximate percentile queries</td><td><a href="/docs/latest/development/extensions-contrib/spectator-histogram">link</a></td></tr><tr><td>druid-rabbit-indexing-service</td><td>Support for creating and managing <a href="https://www.rabbitmq.com/" target="_blank" rel="noopener noreferrer">RabbitMQ</a> indexing tasks</td><td><a href="/docs/latest/development/extensions-contrib/rabbit-super-stream-injestion">link</a></td></tr><tr><td>druid-ranger-security</td><td>Support for access control through Apache Ranger.</td><td><a href="/docs/latest/development/extensions-contrib/druid-ranger-security">link</a></td></tr></tbody></table> | 
 | <h2 class="anchor anchorWithStickyNavbar_LWe7" id="promoting-community-extensions-to-core-extensions">Promoting community extensions to core extensions<a href="#promoting-community-extensions-to-core-extensions" class="hash-link" aria-label="Direct link to Promoting community extensions to core extensions" title="Direct link to Promoting community extensions to core extensions"></a></h2> | 
 | <p>Please post on <a href="https://lists.apache.org/list.html?dev@druid.apache.org" target="_blank" rel="noopener noreferrer">dev@druid.apache.org</a> if you'd like an extension to be promoted to core. | 
 | If we see a community extension actively supported by the community, we can promote it to core based on community feedback.</p> | 
 | <p>For information how to create your own extension, please see <a href="/docs/latest/development/modules">here</a>.</p> | 
 | <h2 class="anchor anchorWithStickyNavbar_LWe7" id="loading-extensions">Loading extensions<a href="#loading-extensions" class="hash-link" aria-label="Direct link to Loading extensions" title="Direct link to Loading extensions"></a></h2> | 
 | <h3 class="anchor anchorWithStickyNavbar_LWe7" id="loading-core-extensions">Loading core extensions<a href="#loading-core-extensions" class="hash-link" aria-label="Direct link to Loading core extensions" title="Direct link to Loading core extensions"></a></h3> | 
 | <p>Apache Druid bundles all <a href="/docs/latest/configuration/extensions#core-extensions">core extensions</a> out of the box. | 
 | See the <a href="/docs/latest/configuration/extensions#core-extensions">list of extensions</a> for your options. You | 
 | can load bundled extensions by adding their names to your common.runtime.properties | 
 | <code>druid.extensions.loadList</code> property. For example, to load the postgresql-metadata-storage and | 
 | druid-hdfs-storage extensions, use the configuration:</p> | 
 | <div class="language-properties codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-properties codeBlock_bY9V thin-scrollbar" style="color:#bfc7d5;background-color:#292d3e"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">druid.extensions.loadList=["postgresql-metadata-storage", "druid-hdfs-storage"]</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div> | 
 | <p>These extensions are located in the <code>extensions</code> directory of the distribution.</p> | 
 | <div class="theme-admonition theme-admonition-info admonition_xJq3 alert alert--info"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_BuS1"><p>Druid bundles two sets of configurations: one for the <a href="/docs/latest/tutorials/">quickstart</a> and | 
 | one for a <a href="/docs/latest/tutorials/cluster">clustered configuration</a>. Make sure you are updating the correct | 
 | <code>common.runtime.properties</code> for your setup.</p></div></div> | 
 | <div class="theme-admonition theme-admonition-info admonition_xJq3 alert alert--info"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_BuS1"><p>Because of licensing, the mysql-metadata-storage extension does not include the required MySQL JDBC driver. For instructions | 
 | on how to install this library, see the <a href="/docs/latest/development/extensions-core/mysql">MySQL extension page</a>.</p></div></div> | 
 | <h3 class="anchor anchorWithStickyNavbar_LWe7" id="loading-community-extensions">Loading community extensions<a href="#loading-community-extensions" class="hash-link" aria-label="Direct link to Loading community extensions" title="Direct link to Loading community extensions"></a></h3> | 
 | <p>You can also load community and third-party extensions not already bundled with Druid. To do this, first download the extension and | 
 | then install it into your <code>extensions</code> directory. You can download extensions from their distributors directly, or | 
 | if they are available from Maven, the included <a href="/docs/latest/operations/pull-deps">pull-deps</a> can download them for you. To use <em>pull-deps</em>, | 
 | specify the full Maven coordinate of the extension in the form <code>groupId:artifactId:version</code>. For example, | 
 | for the (hypothetical) extension <em>com.example:druid-example-extension:1.0.0</em>, run:</p> | 
 | <div class="language-shell codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#bfc7d5;--prism-background-color:#292d3e"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-shell codeBlock_bY9V thin-scrollbar" style="color:#bfc7d5;background-color:#292d3e"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#bfc7d5"><span class="token plain">java \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  -cp "lib/*" \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  -Ddruid.extensions.directory="extensions" \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  -Ddruid.extensions.hadoopDependenciesDir="hadoop-dependencies" \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  org.apache.druid.cli.Main tools pull-deps \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  --no-default-hadoop \</span><br></span><span class="token-line" style="color:#bfc7d5"><span class="token plain">  -c "com.example:druid-example-extension:1.0.0"</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div> | 
 | <p>You only have to install the extension once. Then, add <code>"druid-example-extension"</code> to | 
 | <code>druid.extensions.loadList</code> in common.runtime.properties to instruct Druid to load the extension.</p> | 
 | <div class="theme-admonition theme-admonition-info admonition_xJq3 alert alert--info"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_BuS1"><p>Please make sure all the Extensions related configuration properties listed <a href="/docs/latest/configuration/#extensions">here</a> are set correctly.</p></div></div> | 
 | <div class="theme-admonition theme-admonition-info admonition_xJq3 alert alert--info"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 14 16"><path fill-rule="evenodd" d="M7 2.3c3.14 0 5.7 2.56 5.7 5.7s-2.56 5.7-5.7 5.7A5.71 5.71 0 0 1 1.3 8c0-3.14 2.56-5.7 5.7-5.7zM7 1C3.14 1 0 4.14 0 8s3.14 7 7 7 7-3.14 7-7-3.14-7-7-7zm1 3H6v5h2V4zm0 6H6v2h2v-2z"></path></svg></span>info</div><div class="admonitionContent_BuS1"><p>The Maven <code>groupId</code> for almost every <a href="/docs/latest/configuration/extensions#community-extensions">community extension</a> is <code>org.apache.druid.extensions.contrib</code>. The <code>artifactId</code> is the name | 
 | of the extension, and the version is the latest Druid stable version.</p></div></div> | 
 | <h3 class="anchor anchorWithStickyNavbar_LWe7" id="loading-extensions-from-the-classpath">Loading extensions from the classpath<a href="#loading-extensions-from-the-classpath" class="hash-link" aria-label="Direct link to Loading extensions from the classpath" title="Direct link to Loading extensions from the classpath"></a></h3> | 
 | <p>If you add your extension jar to the classpath at runtime, Druid will also load it into the system. This mechanism is relatively easy to reason about, | 
 | but it also means that you have to ensure that all dependency jars on the classpath are compatible. That is, Druid makes no provisions while using | 
 | this method to maintain class loader isolation so you must make sure that the jars on your classpath are mutually compatible.</p></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/docs/latest/configuration/"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">Configuration reference</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/docs/latest/configuration/logging"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">Logging</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#core-extensions" class="table-of-contents__link toc-highlight">Core extensions</a></li><li><a href="#community-extensions" class="table-of-contents__link toc-highlight">Community extensions</a></li><li><a href="#promoting-community-extensions-to-core-extensions" class="table-of-contents__link toc-highlight">Promoting community extensions to core extensions</a></li><li><a href="#loading-extensions" class="table-of-contents__link toc-highlight">Loading extensions</a><ul><li><a href="#loading-core-extensions" class="table-of-contents__link toc-highlight">Loading core extensions</a></li><li><a href="#loading-community-extensions" class="table-of-contents__link toc-highlight">Loading community extensions</a></li><li><a href="#loading-extensions-from-the-classpath" class="table-of-contents__link toc-highlight">Loading extensions from the classpath</a></li></ul></li></ul></div></div></div></div></main></div></div></div><footer class="footer"><div class="container container-fluid"><div class="footer__bottom text--center"><div class="margin-bottom--sm"><img src="/img/favicon.png" class="footer__logo themedComponent_mlkZ themedComponent--light_NVdE"><img src="/img/favicon.png" class="footer__logo themedComponent_mlkZ themedComponent--dark_xIcU"></div><div class="footer__copyright">Copyright © 2025 Apache Software Foundation. Except where otherwise noted, licensed under CC BY-SA 4.0. Apache Druid, Druid, and the Druid logo are either registered trademarks or trademarks of The Apache Software Foundation in the United States and other countries.</div></div></div></footer></div> | 
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