diff --git a/android/mutator.go b/android/mutator.go
index df68726..0d253eb 100644
--- a/android/mutator.go
+++ b/android/mutator.go
@@ -143,8 +143,8 @@
 
 	AddDependency(module blueprint.Module, tag blueprint.DependencyTag, name ...string)
 	AddReverseDependency(module blueprint.Module, tag blueprint.DependencyTag, name string)
-	CreateVariations(...string) []blueprint.Module
-	CreateLocalVariations(...string) []blueprint.Module
+	CreateVariations(...string) []Module
+	CreateLocalVariations(...string) []Module
 	SetDependencyVariation(string)
 	SetDefaultDependencyVariation(*string)
 	AddVariationDependencies([]blueprint.Variation, blueprint.DependencyTag, ...string)
@@ -285,28 +285,32 @@
 	b.bp.AddReverseDependency(module, tag, name)
 }
 
-func (b *bottomUpMutatorContext) CreateVariations(variations ...string) []blueprint.Module {
+func (b *bottomUpMutatorContext) CreateVariations(variations ...string) []Module {
 	modules := b.bp.CreateVariations(variations...)
 
+	aModules := make([]Module, len(modules))
 	for i := range variations {
-		base := modules[i].(Module).base()
+		aModules[i] = modules[i].(Module)
+		base := aModules[i].base()
 		base.commonProperties.DebugMutators = append(base.commonProperties.DebugMutators, b.MutatorName())
 		base.commonProperties.DebugVariations = append(base.commonProperties.DebugVariations, variations[i])
 	}
 
-	return modules
+	return aModules
 }
 
-func (b *bottomUpMutatorContext) CreateLocalVariations(variations ...string) []blueprint.Module {
+func (b *bottomUpMutatorContext) CreateLocalVariations(variations ...string) []Module {
 	modules := b.bp.CreateLocalVariations(variations...)
 
+	aModules := make([]Module, len(modules))
 	for i := range variations {
-		base := modules[i].(Module).base()
+		aModules[i] = modules[i].(Module)
+		base := aModules[i].base()
 		base.commonProperties.DebugMutators = append(base.commonProperties.DebugMutators, b.MutatorName())
 		base.commonProperties.DebugVariations = append(base.commonProperties.DebugVariations, variations[i])
 	}
 
-	return modules
+	return aModules
 }
 
 func (b *bottomUpMutatorContext) SetDependencyVariation(variation string) {