Quarkus multi-module project — duplicate ProjectModel generated in main module despite quarkus.kogito.codegen.disable=true

[shrinivasuk]

Hi team,

I’m working on a multi-module Quarkus + Drools (Kogito) project and ran into a consistent issue where multiple ProjectModel classes are generated — one in my rules module (expected), and another in my main (API) module (unexpected, empty).
Even though I’ve disabled codegen in the main module via both Maven and Quarkus properties, Quarkus still generates an empty ProjectModel under target/generated-sources/kogito for the main module.
This leads to rule discovery conflicts and runtime errors because the empty model shadows the correct one from the rules module.

XYZ-parent

1. XYZ-common → shared utilities
   2)XYZ-rules → contains .drl/.xls rules, runs Kogito codegen
   3)XYZ-main → Quarkus app (REST APIs, CDI), depends on XYZ-rules

XYZ-rules/pom.xml

<project>
  <parent>...</parent>
  <artifactId>XYZ-rules</artifactId>
  <packaging>jar</packaging>

  <dependencies>
    <dependency>
      <groupId>org.drools</groupId>
      <artifactId>drools-quarkus-rules</artifactId>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>org.kie.kogito</groupId>
        <artifactId>kogito-maven-plugin</artifactId>
        <version>${kogito.bom.version}</version>
        <executions>
          <execution>
            <phase>generate-sources</phase>
            <goals><goal>generateModel</goal></goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>

This correctly generates
xyz-rules/target/generated-sources/kogito/org/drools/project/model/ProjectModel.java

<project>
  <parent>...</parent>
  <artifactId>xyz-main</artifactId>

  <dependencies>
    <dependency>
      <groupId>com.example</groupId>
      <artifactId>xyz-rules</artifactId>
      <version>${project.version}</version>
    </dependency>
    <dependency>
      <groupId>io.quarkus</groupId>
      <artifactId>quarkus-resteasy-reactive</artifactId>
    </dependency>
  </dependencies>

  <build>
    <plugins>
      <plugin>
        <groupId>${quarkus.platform.group-id}</groupId>
        <artifactId>quarkus-maven-plugin</artifactId>
        <version>${quarkus.platform.version}</version>
        <executions>
          <execution>
            <goals><goal>build</goal></goals>
          </execution>
        </executions>
      </plugin>
    </plugins>
  </build>
</project>

application.properties:
quarkus.kogito.codegen.disable=true

xyz-main/target/generated-sources/kogito/org/drools/project/model/ProjectModel.java
and

  @Override
    public java.util.List<Model> getModels() {
        return java.util.Arrays.asList();
    }

Questions:

1) Is this the intended behavior of quarkus-kogito extension in multi-module projects?
2) Should quarkus.kogito.codegen.disable=true prevent this automatic model generation in dependent modules?
3) Is there a supported way to isolate Kogito/Drools code generation to only one module (like xyz-rules)?

[fah-kmd-dk]

The versions used in multi-module project are

• Quarkus: 3.25.4
• Drools: 10.0.0
• Kogito: 10.1.0

We are very interested in a working multi-module kogito solution :)