diff --git a/src/Codegen/Constraints/StringBuilder.php b/src/Codegen/Constraints/StringBuilder.php
index 558eb57..1142992 100644
--- a/src/Codegen/Constraints/StringBuilder.php
+++ b/src/Codegen/Constraints/StringBuilder.php
@@ -67,8 +67,9 @@ public function build(): this {
         $factory = $this->ctx->getHackCodegenFactory();
         $members = \HH\Lib\Vec\map(
           $enum,
-          $member ==> $factory->codegenEnumMember(Str\uppercase($member))
-            ->setValue($member, HackBuilderValues::export()),
+          $member ==> Str\replace_every($member, dict[':' => '_', '.' => '_'])
+            |> Str\uppercase($$)  
+            |> $factory->codegenEnumMember($$)->setValue($member, HackBuilderValues::export()),
         );
         $enumName = $this->typed_schema['hackEnum'] ?? null;
         invariant($enumName is string, 'hackEnum is required when generating hack enum.');