diff --git a/src/hissp/macros.lissp b/src/hissp/macros.lissp
index 7889d9c76..f3e1c6b69 100644
--- a/src/hissp/macros.lissp
+++ b/src/hissp/macros.lissp
@@ -883,7 +883,7 @@ Hidden doctest adds bundled macros for REPL-consistent behavior.
   ;;    >>> b'Fully-qualified b# macro at read time.'
   ;;    b'Fully-qualified b# macro at read time.'
   ;;
-  ;;    #> H:##b"Read-time b# via alias."
+  ;;    #> =H:#b"Read-time b# via alias."
   ;;    >>> b'Read-time b# via alias.'
   ;;    b'Read-time b# via alias.'
   ;;
@@ -963,8 +963,8 @@ Hidden doctest adds bundled macros for REPL-consistent behavior.
 
   .. code-block:: REPL
 
-     #> @##str.swapcase
-     #..@##str.title
+     #> =@#str.swapcase
+     #..=@#str.title
      #..(define spam 'spam) ; Unlike Python def, not always a function.
      >>> # hissp.macros.._macro_.define
      ... __import__('builtins').globals().update(
@@ -2828,7 +2828,7 @@ Creates a lambda of arity {X} containing a `^*#<QzHAT_QzSTAR_QzHASH_>`
 
   .. code-block:: REPL
 
-     #> (op#add 5 file=spy##sys..stdout(op#mul 7 3))
+     #> (op#add 5 file=spy#sys..stdout(op#mul 7 3))
      >>> __import__('operator').add(
      ...   (5),
      ...   # hissp.._macro_._spy
@@ -2861,7 +2861,7 @@ Creates a lambda of arity {X} containing a `^*#<QzHAT_QzSTAR_QzHASH_>`
 
   .. code-block:: REPL
 
-     #> file=time##sys..stdout(time..sleep .05)
+     #> file=time#sys..stdout(time..sleep .05)
      >>> # hissp.macros.._macro_.let
      ... (lambda _QzPMWTVFTZz_time=__import__('time').time_ns:
      ...   # hissp.macros.._macro_.letQz_from
diff --git a/src/hissp/reader.py b/src/hissp/reader.py
index 7952c475e..2279555a1 100644
--- a/src/hissp/reader.py
+++ b/src/hissp/reader.py
@@ -75,7 +75,7 @@
       |['`,]
       |[.][#]
       # Any atom that ends in ``#``, but not ``.#`` or ``\#``.
-      |(?:[^\\ \n"();#]|\\.)*(?:[^.\\ \n"();#]|\\.)[#]+
+      |(?:[^\\ \n"();#]|\\.)*(?:[^.\\ \n"();#]|\\.)[#]
      )
     |(?P<string>
       [#]?  # raw?
@@ -436,12 +436,11 @@ def _get_counter(self) -> int:
 
     def _custom_macro(self, form, tag: str):
         assert tag.endswith("#")
-        arity = tag.replace(R"\#", "").count("#")
+        arity = tag.replace(R"\=", "").count("=")
+        *keywords, label = re.findall(r"((?:[^=\\]|\\.)*[=#])", tag)
+        arity += bool(label)
         assert arity > 0
-        *keywords, label = re.findall(r"((?:[^=\\]|\\.)*(?:=|#+))", tag)
-        if len(keywords) > arity:
-            raise SyntaxError(f"Not enough # for each = in {tag!r}")
-        label = label[:-arity]
+        label = label[:-1]
         label = force_munge(self.escape(label))
         label = re.sub(r"(^\.)", lambda m: force_qz_encode(m[1]), label)
         fn: Fn[[str], Fn] = self._fully_qualified if ".." in label else self._local