diff --git a/extlib/benz/include/picrin.h b/extlib/benz/include/picrin.h
index e5419c24..c1b16cd9 100644
--- a/extlib/benz/include/picrin.h
+++ b/extlib/benz/include/picrin.h
@@ -193,6 +193,10 @@ void pic_load_cstr(pic_state *, const char *);
 void pic_define(pic_state *, const char *, pic_value);
 void pic_defun(pic_state *, const char *, pic_func_t);
 void pic_defvar(pic_state *, const char *, pic_value, struct pic_proc *);
+/* functions suffixed with '_' will not perform automatic export */
+void pic_define_(pic_state *, const char *, pic_value);
+void pic_defun_(pic_state *, const char *, pic_func_t);
+void pic_defvar_(pic_state *, const char *, pic_value, struct pic_proc *);
 
 pic_value pic_ref(pic_state *, struct pic_lib *, const char *);
 void pic_set(pic_state *, struct pic_lib *, const char *, pic_value);
diff --git a/extlib/benz/vm.c b/extlib/benz/vm.c
index 6989c465..f661f10a 100644
--- a/extlib/benz/vm.c
+++ b/extlib/benz/vm.c
@@ -1137,7 +1137,7 @@ pic_defun_vm(pic_state *pic, const char *name, pic_sym *uid, pic_func_t func)
 }
 
 void
-pic_define(pic_state *pic, const char *name, pic_value val)
+pic_define_(pic_state *pic, const char *name, pic_value val)
 {
   pic_sym *sym, *uid;
 
@@ -1150,20 +1150,39 @@ pic_define(pic_state *pic, const char *name, pic_value val)
   }
 
   pic_dict_set(pic, pic->globals, uid, val);
+}
 
-  pic_export(pic, sym);
+void
+pic_define(pic_state *pic, const char *name, pic_value val)
+{
+  pic_define_(pic, name, val);
+  pic_export(pic, pic_intern_cstr(pic, name));
+}
+
+void
+pic_defun_(pic_state *pic, const char *name, pic_func_t cfunc)
+{
+  pic_define_(pic, name, pic_obj_value(pic_make_proc(pic, cfunc, name)));
 }
 
 void
 pic_defun(pic_state *pic, const char *name, pic_func_t cfunc)
 {
-  pic_define(pic, name, pic_obj_value(pic_make_proc(pic, cfunc, name)));
+  pic_defun_(pic, name, cfunc);
+  pic_export(pic, pic_intern_cstr(pic, name));
+}
+
+void
+pic_defvar_(pic_state *pic, const char *name, pic_value init, struct pic_proc *conv)
+{
+  pic_define_(pic, name, pic_obj_value(pic_make_var(pic, init, conv)));
 }
 
 void
 pic_defvar(pic_state *pic, const char *name, pic_value init, struct pic_proc *conv)
 {
-  pic_define(pic, name, pic_obj_value(pic_make_var(pic, init, conv)));
+  pic_defvar_(pic, name, init, conv);
+  pic_export(pic, pic_intern_cstr(pic, name));
 }
 
 pic_value