diff --git a/piclib/built-in.scm b/piclib/built-in.scm
index e3093dcb..51cfa5f5 100644
--- a/piclib/built-in.scm
+++ b/piclib/built-in.scm
@@ -92,6 +92,14 @@
                      (dictionary-set! cache atom id)
                      id)))))))
 
+  (define (sc-macro-transformer f)
+    (lambda (expr use-env mac-env)
+      (make-syntactic-closure mac-env '() (f expr use-env))))
+
+  (define (rsc-macro-transformer f)
+    (lambda (expr use-env mac-env)
+      (make-syntactic-closure use-env '() (f expr mac-env))))
+
   (define (er-macro-transformer f)
     (lambda (expr use-env mac-env)
 
@@ -158,16 +166,10 @@
 
       (unwrap (f (wrap expr) inject compare))))
 
-  (define (sc-macro-transformer f)
-    (lambda (expr use-env mac-env)
-      (make-syntactic-closure mac-env '() (f expr use-env))))
-
-  (define (rsc-macro-transformer f)
-    (lambda (expr use-env mac-env)
-      (make-syntactic-closure use-env '() (f expr mac-env))))
-
   (export sc-macro-transformer
-          rsc-macro-transformer))
+          rsc-macro-transformer
+          er-macro-transformer
+          ir-macro-transformer))
 
 ;;; core syntaces
 (define-library (picrin core-syntax)
diff --git a/src/macro.c b/src/macro.c
index 16c7816c..8be145f6 100644
--- a/src/macro.c
+++ b/src/macro.c
@@ -724,222 +724,6 @@ pic_macro_identifier_eq_p(pic_state *pic)
   return pic_bool_value(sc_identifier_eq_p(pic, e1, x, e2, y));
 }
 
-static pic_value
-er_macro_rename(pic_state *pic)
-{
-  pic_sym sym;
-  struct pic_senv *mac_env;
-  struct pic_dict *cxt;
-
-  pic_get_args(pic, "m", &sym);
-
-  mac_env = pic_senv_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 1));
-  cxt = pic_dict_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 2));
-
-  return pic_sym_value(make_identifier(pic, sym, mac_env, cxt));
-}
-
-static pic_value
-er_macro_compare(pic_state *pic)
-{
-  pic_value a, b;
-  struct pic_senv *use_env;
-  pic_sym m, n;
-  struct pic_dict *cxt;
-
-  pic_get_args(pic, "oo", &a, &b);
-
-  if (! pic_sym_p(a) || ! pic_sym_p(b))
-    return pic_false_value();   /* should be an error? */
-
-  use_env = pic_senv_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 0));
-  cxt = pic_dict_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 2));
-
-  m = make_identifier(pic, pic_sym(a), use_env, cxt);
-  n = make_identifier(pic, pic_sym(b), use_env, cxt);
-
-  return pic_bool_value(m == n);
-}
-
-static pic_value
-er_macro_call(pic_state *pic)
-{
-  pic_value expr, use_env, mac_env;
-  struct pic_proc *rename, *compare, *cb;
-  struct pic_dict *cxt;
-
-  pic_get_args(pic, "ooo", &expr, &use_env, &mac_env);
-
-  if (! pic_senv_p(use_env)) {
-    pic_error(pic, "unexpected type of argument 1");
-  }
-  if (! pic_senv_p(mac_env)) {
-    pic_error(pic, "unexpected type of argument 3");
-  }
-
-  cxt = pic_dict_new(pic);
-
-  rename = pic_proc_new(pic, er_macro_rename, "<er-macro-renamer>");
-  pic_proc_cv_init(pic, rename, 3);
-  pic_proc_cv_set(pic, rename, 0, use_env);
-  pic_proc_cv_set(pic, rename, 1, mac_env);
-  pic_proc_cv_set(pic, rename, 2, pic_obj_value(cxt));
-
-  compare = pic_proc_new(pic, er_macro_compare, "<er-macro-comparator>");
-  pic_proc_cv_init(pic, compare, 3);
-  pic_proc_cv_set(pic, compare, 0, use_env);
-  pic_proc_cv_set(pic, compare, 1, mac_env);
-  pic_proc_cv_set(pic, compare, 2, pic_obj_value(cxt));
-
-  cb = pic_proc_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 0));
-
-  return pic_apply3(pic, cb, expr, pic_obj_value(rename), pic_obj_value(compare));
-}
-
-static pic_value
-pic_macro_er_macro_transformer(pic_state *pic)
-{
-  struct pic_proc *cb, *proc;
-
-  pic_get_args(pic, "l", &cb);
-
-  proc = pic_proc_new(pic, er_macro_call, "<er-macro-procedure>");
-  pic_proc_cv_init(pic, proc, 1);
-  pic_proc_cv_set(pic, proc, 0, pic_obj_value(cb));
-
-  return pic_obj_value(proc);
-}
-
-static pic_value
-ir_macro_inject(pic_state *pic)
-{
-  pic_sym sym;
-  struct pic_senv *use_env;
-  struct pic_dict *cxt;
-
-  pic_get_args(pic, "m", &sym);
-
-  use_env = pic_senv_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 0));
-  cxt = pic_dict_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 2));
-
-  return pic_sym_value(make_identifier(pic, sym, use_env, cxt));
-}
-
-static pic_value
-ir_macro_compare(pic_state *pic)
-{
-  pic_value a, b;
-  struct pic_senv *mac_env;
-  pic_sym m, n;
-  struct pic_dict *cxt;
-
-  pic_get_args(pic, "oo", &a, &b);
-
-  if (! pic_sym_p(a) || ! pic_sym_p(b))
-    return pic_false_value();   /* should be an error? */
-
-  mac_env = pic_senv_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 1));
-  cxt = pic_dict_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 2));
-
-  m = make_identifier(pic, pic_sym(a), mac_env, cxt);
-  n = make_identifier(pic, pic_sym(b), mac_env, cxt);
-
-  return pic_bool_value(m == n);
-}
-
-static pic_value
-ir_macro_wrap(pic_state *pic, pic_value expr, struct pic_senv *use_env, struct pic_dict *cxt, pic_value *ir)
-{
-  if (pic_sym_p(expr)) {
-    pic_value r;
-    r = pic_sym_value(make_identifier(pic, pic_sym(expr), use_env, cxt));
-    *ir = pic_acons(pic, r, expr, *ir);
-    return r;
-  }
-  else if (pic_pair_p(expr)) {
-    return pic_cons(pic,
-                    ir_macro_wrap(pic, pic_car(pic, expr), use_env, cxt, ir),
-                    ir_macro_wrap(pic, pic_cdr(pic, expr), use_env, cxt, ir));
-  }
-  else {
-    return expr;
-  }
-}
-
-static pic_value
-ir_macro_unwrap(pic_state *pic, pic_value expr, struct pic_senv *mac_env, struct pic_dict *cxt, pic_value *ir)
-{
-  if (pic_sym_p(expr)) {
-    pic_value r;
-    if (pic_test(r = pic_assq(pic, expr, *ir))) {
-      return pic_cdr(pic, r);
-    }
-    return pic_sym_value(make_identifier(pic, pic_sym(expr), mac_env, cxt));
-  }
-  else if (pic_pair_p(expr)) {
-    return pic_cons(pic,
-                    ir_macro_unwrap(pic, pic_car(pic, expr), mac_env, cxt, ir),
-                    ir_macro_unwrap(pic, pic_cdr(pic, expr), mac_env, cxt, ir));
-  }
-  else {
-    return expr;
-  }
-}
-
-static pic_value
-ir_macro_call(pic_state *pic)
-{
-  pic_value expr, use_env, mac_env;
-  struct pic_proc *inject, *compare, *cb;
-  struct pic_dict *cxt;
-  pic_value ir = pic_nil_value();
-
-  pic_get_args(pic, "ooo", &expr, &use_env, &mac_env);
-
-  if (! pic_senv_p(use_env)) {
-    pic_error(pic, "unexpected type of argument 1");
-  }
-  if (! pic_senv_p(mac_env)) {
-    pic_error(pic, "unexpected type of argument 3");
-  }
-
-  cxt = pic_dict_new(pic);
-
-  inject = pic_proc_new(pic, ir_macro_inject, "<ir-macro-injecter>");
-  pic_proc_cv_init(pic, inject, 3);
-  pic_proc_cv_set(pic, inject, 0, use_env);
-  pic_proc_cv_set(pic, inject, 1, mac_env);
-  pic_proc_cv_set(pic, inject, 2, pic_obj_value(cxt));
-
-  compare = pic_proc_new(pic, ir_macro_compare, "<ir-macro-comparator>");
-  pic_proc_cv_init(pic, compare, 3);
-  pic_proc_cv_set(pic, compare, 0, use_env);
-  pic_proc_cv_set(pic, compare, 1, mac_env);
-  pic_proc_cv_set(pic, compare, 2, pic_obj_value(cxt));
-
-  cb = pic_proc_ptr(pic_proc_cv_ref(pic, pic_get_proc(pic), 0));
-
-  expr = ir_macro_wrap(pic, expr, pic_senv_ptr(use_env), cxt, &ir);
-  expr = pic_apply3(pic, cb, expr, pic_obj_value(inject), pic_obj_value(compare));
-  expr = ir_macro_unwrap(pic, expr, pic_senv_ptr(mac_env), cxt, &ir);
-
-  return expr;
-}
-
-static pic_value
-pic_macro_ir_macro_transformer(pic_state *pic)
-{
-  struct pic_proc *cb, *proc;
-
-  pic_get_args(pic, "l", &cb);
-
-  proc = pic_proc_new(pic, ir_macro_call, "<ir-macro-procedure>");
-  pic_proc_cv_init(pic, proc, 1);
-  pic_proc_cv_set(pic, proc, 0, pic_obj_value(cb));
-
-  return pic_obj_value(proc);
-}
-
 static pic_value
 pic_macro_make_identifier(pic_state *pic)
 {
@@ -966,8 +750,6 @@ pic_init_macro(pic_state *pic)
     pic_defun(pic, "make-syntactic-closure", pic_macro_make_sc);
     pic_defun(pic, "identifier?", pic_macro_identifier_p);
     pic_defun(pic, "identifier=?", pic_macro_identifier_eq_p);
-    pic_defun(pic, "er-macro-transformer", pic_macro_er_macro_transformer);
-    pic_defun(pic, "ir-macro-transformer", pic_macro_ir_macro_transformer);
     pic_defun(pic, "make-identifier", pic_macro_make_identifier);
   }
 }