diff --git a/tsup.config.ts b/tsup.config.ts
index d77aa977..a2ef9131 100644
--- a/tsup.config.ts
+++ b/tsup.config.ts
@@ -23,5 +23,5 @@ export default defineConfig({
 
 function addMjsExtension(content) {
   // This regex looks for relative import paths that don't have a file extension
-  return content.replace(/from\s+['"](\.\/|\.\.\/)(?![^'"\s]+?\.\w+['"])([^'"\s]+?)['"];/g, "from '$1$2.mjs';");
+  return content.replace(/from\s+['"](\.\/|\.\.\/)(?![^'"\s]+?\/)['"]([^'"\s]+?)['"];/g, "from '$1$2.mjs';");
 }