diff --git a/src/main/java/com/google/devtools/build/lib/packages/AspectDefinition.java b/src/main/java/com/google/devtools/build/lib/packages/AspectDefinition.java
index 10ba3ff..14bade6 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/AspectDefinition.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/AspectDefinition.java
@@ -181,7 +181,8 @@
      * <p>Note that {@code AspectFactory} instances are expected in the second argument, but we
      * cannot reference that interface here.
      */
-    public Builder attributeAspect(
+    @SafeVarargs
+    public final Builder attributeAspect(
         String attribute, Class<? extends AspectFactory<?, ?, ?>>... aspectFactories) {
       Preconditions.checkNotNull(attribute);
       for (Class<? extends AspectFactory<?, ?, ?>> aspectFactory : aspectFactories) {