Quarkus Extension

MicroStream comes with a Quarkus extension which allows accessing the functionality of MicroStream through the usage of a few annotations.

MicroStream extension is not available on the Quarkus multiverse nor on the Quarkus code generator.

It is available after adding the MicroStream Quarkus extension to your application. You can use the following Maven command for example:

Add Quarkus extension
mvn quarkus:add-extension -Dextensions="one.microstream:microstream-quarkus-extension:08.00.00-MS-GA"

The extension requires Quarkus 2.11.1 as a minimal version.

If you are running Quarkus 3, use the following command in your project:

Add Quarkus 3 extension
mvn quarkus:add-extension -Dextensions="one.microstream:microstream-quarkus3-extension:09.00.00-MS-GA"

The migration from version 2 to 3 doesn’t require any code changes related to the MicroStream integration classes.


The configuration of the StorageManager can be done using key/value pairs that are provided by Quarkus configuration. The configuration keys must be prefixed by one.microstream


Since the - character is not supported in some sources (like the environment variables), you can also define the configuration keys using the . character.


The configured and started StorageManager is a CDI bean and thus can be injected or retrieved programmatically.

private StorageManager storageManager;

public void someMethod() {
    StorageManager storageManager = CDI.current().select(StorageManager.class).get();

public void someMethodWithArc() {
    StorageManager storageManager = Arc.container().select(StorageManager.class).get();

The StorageManager configuration can be customized by CDI beans that implement the interface one.microstream.integrations.quarkus.types.config.EmbeddedStorageFoundationCustomizer. The customize method is called with an EmbeddedStorageFoundation which allows you to fully customize the StorageManager that will be created. You can for example, add the specific Type Handlers for JDK 8 as described on the documentation.

After the StorageManager is created, the CDI beans that implement one.microstream.integrations.quarkus.types.config.StorageManagerInitializer are called. You have the opportunity to perform actions on the StorageManager or root object. Following rules apply to the StorageManager that is passed to the initialize method of the interface.

  • The StorageManager is already started unless you specified the configuration value one.microstream.autoStart=false.

  • If you have used the @Storage annotation on a class, the StorageManager is already associated with an instance of that class as the Root object.

Root object

The root object can be indicated by using the @Storage annotation on the class. This annotation converts the POJO into a CDI bean (there is no need to use any scope-defining annotation) with Application Scope.

Besides converting it into a CDI bean, any field injection within this class is also resolved.

The integration also defines the instance of the class that is created as the root object (StorageManager.setRoot()) and stores the initial value (StorageManager.storeRoot()) when storageManager does not have a root object assigned yet (this happens only the very first time when you start up your application and the storage doesn’t contain any data yet)

The POJO must have a (default) no-argument constructor so that the integration can create an instance of it.

You can only annotate 1 class with the @Storage annotation, if you have marked multiple, the start of your application will fail with an Exception.

Debug logging

You can activate debug logging to analyse the behaviour of the MicroStream core or the extension.

Add the following entry to application.properties file:


This will set the debug level of all loggers related to MicroStream to the Debug level.


The above setting only activate the debug level for the extension code.