diff --git a/packages/swc-plugin-workflow/transform/src/lib.rs b/packages/swc-plugin-workflow/transform/src/lib.rs
index b43b941f90..9b424934d5 100644
--- a/packages/swc-plugin-workflow/transform/src/lib.rs
+++ b/packages/swc-plugin-workflow/transform/src/lib.rs
@@ -1578,13 +1578,6 @@ impl StepTransform {
         is_workflow: bool,
     ) -> String {
         match fn_name {
-            Some(name) if name.starts_with("__builtin") => {
-                // Special case for __builtin functions: use only the function name.
-                // These are internal SDK functions that are referenced by name in the
-                // workflow VM runtime (packages/core/src/workflow.ts), so they need
-                // stable, version-independent IDs.
-                name.to_string()
-            }
             Some(name) => {
                 let prefix = if is_workflow { "workflow" } else { "step" };
                 naming::format_name(prefix, &self.get_module_path(), name)