wiremock adding multiple mapping directories

Question

My Java application creates a wiremock to a mapping directory.

final var  baseDir = System.getProperty("user.dir");
final var mappingsDir = baseDir + "/src/test/resources/wm-mappings/app1";

Under app1 I have another folder called mappings.

wireMockServer = new WireMockServer(WireMockConfiguration
    .options()
    .port(56008)
    .usingFilesUnderDirectory(mappingsDir));

This works fine, but I want to include another directory. How can I do that?