Why might Lombok cause issues in multi-module Maven builds with annotation processor ordering?

Annotation processors run in whatever order the build tool discovers and applies them, and if a project uses multiple processors together (Lombok alongside MapStruct, or a custom code-generating processor), the order they run in can matter — particularly since Lombok's generated methods need to already exist by the time another processor that depends on seeing them runs its own analysis.

<annotationProcessorPaths>
    <path>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
    </path>
    <path>
        <groupId>org.mapstruct</groupId>
        <artifactId>mapstruct-processor</artifactId>
    </path>
</annotationProcessorPaths>

Explicitly declaring annotationProcessorPaths (rather than relying on whatever processors happen to be found on the classpath) lets you control this ordering deliberately, which becomes especially relevant in multi-module builds where different modules might otherwise pick up processors in inconsistent orders depending on classpath assembly quirks, leading to intermittent, hard-to-reproduce build failures where a processor can't find methods Lombok hadn't generated yet.

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