---
id: experimental-features
title: "Experimental features"
---

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The following features are marked [experimental](./experimental.md) in the Druid docs.

This document includes each page that mentions an experimental feature. To graduate a feature, remove all mentions of its experimental status on all relevant pages.

Note that this document does not track the status of contrib extensions, all of which are considered experimental.

## SQL-based ingestion

- [SQL-based ingestion](../multi-stage-query/index.md)
- [SQL-based ingestion concepts](../multi-stage-query/concepts.md)
- [SQL-based ingestion and multi-stage query task API](../multi-stage-query/api.md)

## Indexer process

- [Indexer process](../design/indexer.md)
- [Processes and servers](../design/processes.md#indexer-process-optional)

## Kubernetes

- [Kubernetes](../development/extensions-core/kubernetes.md)

## Segment locking

- [Configuration reference](../configuration/index.md#overlord-operations)
- [Task reference](../ingestion/tasks.md#locking)
- [Design](../design/architecture.md#availability-and-consistency)

## Front coding

- [Ingestion spec reference](../ingestion/ingestion-spec.md#front-coding)

## Other configuration properties

- [Configuration reference](../configuration/index.md)
   - `CLOSED_SEGMENTS_SINKS` mode
   - Expression processing configuration `druid.expressions.allowNestedArrays`