In addition to Fusion’s built-in query stages, Lucidworks provides the Query Stage SDK for developing your own custom query stages with Java. All of the resources are provided in a public GitHub repository.

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Getting started

Clone the repository to get started: 
git clone https://github.com/lucidworks/query-stage-sdk
See Gradle quickstart documentation for more information on Java Projects.
The Query Stage SDK requires the Fusion Search DSL.

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Query Stage SDK library

The Java SDK library contains the classes and interfaces for building new query plugin stages. You’ll find it in the query-stage-plugin-sdk directory.

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Example plugin stage

The example query stage plugin contains an example of how a plugin can be implemented as well as information on how to build and deploy the plugin. You’ll find it in the examples/sample-plugin-stage directory.