```common lisp
;;; -*- Mode: Lisp; indent-tabs-mode: nil -*-

(in-package :swap-bytes)

#+x86
(defun swap-bytes-16 (integer)
  (declare (type (unsigned-byte 16) integer))
  (swap-bytes-16 integer))

(defun swap-bytes-32 (integer)
  (declare (type (unsigned-byte 32) integer))
  (swap-bytes-32 integer))

#+x86-64
(defun swap-bytes-64 (integer)
  (declare (type (unsigned-byte 64) integer))
  (swap-bytes-64 integer))
```

Add reader conditional for clarity
user
```common lisp
;;; -*- Mode: Lisp; indent-tabs-mode: nil -*-

(in-package :swap-bytes)

#+x86
(defun swap-bytes-16 (integer)
  (declare (type (unsigned-byte 16) integer))
  (swap-bytes-16 integer))

#+(or x86 x86-64)
(defun swap-bytes-32 (integer)
  (declare (type (unsigned-byte 32) integer))
  (swap-bytes-32 integer))

#+x86-64
(defun swap-bytes-64 (integer)
  (declare (type (unsigned-byte 64) integer))
  (swap-bytes-64 integer))
```
assistant