static Class byteBuddy_quicklyAddSubClass(S className, Class baseClass) {
  byte[] classData = byteBuddy_newSubClass_bytes(className, baseClass);
  File jar = programFile(className + ".jar");
  createZipFileWithSingleBinaryFile(jar, className + ".class", classData);
  addLibraryToCurrentProgram(jar);
  ret classForName(className);
}