diff --git a/src/main/java/com/google/devtools/build/lib/bazel/bzlmod/SingleExtensionEvalFunction.java b/src/main/java/com/google/devtools/build/lib/bazel/bzlmod/SingleExtensionEvalFunction.java
index 889f85ef5f40ab..cd85ff18046bbb 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/bzlmod/SingleExtensionEvalFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/bzlmod/SingleExtensionEvalFunction.java
@@ -86,6 +86,7 @@ public void setRepositoryRemoteExecutor(RepositoryRemoteExecutor repositoryRemot
     this.repositoryRemoteExecutor = repositoryRemoteExecutor;
   }
 
+  @Nullable
   @Override
   public SkyValue compute(SkyKey skyKey, Environment env)
       throws SkyFunctionException, InterruptedException {
@@ -161,6 +162,7 @@ public SkyValue compute(SkyKey skyKey, Environment env)
     try (Mutability mu =
         Mutability.create("module extension", usagesValue.getExtensionUniqueName())) {
       StarlarkThread thread = new StarlarkThread(mu, starlarkSemantics);
+      thread.setPrintHandler(Event.makeDebugPrintHandler(env.getListener()));
       ModuleExtensionContext moduleContext =
           createContext(env, usagesValue, starlarkSemantics, extension);
       threadContext.storeInThread(thread);