anchor.diff:                   (map nil #'u8 octets)
                    (u8 0)))
                (arr (element-type value)
  -               (align 4)
                  (let ((length-position (file-position stream)))
                    (u32 0)
  -                 (typecase element-type
  -                   ((or (member :int64 :uint64 :double)
  -                        (cons (member :struct :dict-entry)))
  -                    (align 8)))
  +                 (align (alignment element-type))
                    (let ((start-position (file-position stream)))
                      (pack-seq (circular-list element-type) value)
                      (let ((end-position (file-position stream)))
  
positive.code:                (pack-1 :signature type)
                 (pack-1 (first type) value))
               (pack-1 (type value)
                 (etypecase type
                   ((eql :byte) (u8 value))
                   ((eql :boolean) (u32 (if value 1 0)))
  
negative.code:                      (u32 (- end-position start-position))
                       (file-position stream end-position)))))
               (struct (field-types value)
                 (map nil (lambda (type element)
                            (pack-1 type element))
                      field-types value))
  