anchor.diff:              |xmlns:dc| "http://purl.org/dc/elements/1.1/"
               |xml:lang| "en")
       (|title| ,(format nil "Significant changes in SBCL benchmark results on ~A" host))
  -    (|modified| ,(format-atom-decoded-time last-modified))
  +    (|modified| ,(format-atom-decoded-time last-modified 1))
       (|id| ,(format nil "tag:sbcl.boinkor.net,~A:/bench/~A" (nth-value 5 (get-decoded-time)) implementation))
       ((|link| |rel| "alternate"
                |type| "text/html"
  
positive.code: (defun days-ago (days)
    (- (get-universal-time) (* 86400 days)))
  
  (defun format-atom-decoded-time (&optional (days 0))
    (multiple-value-bind (second minute hour date month year day daylight-p zone) (decode-universal-time (days-ago days))
      (declare (ignore day hour minute second daylight-p zone))
      (format nil "~4,1,0,'0@A-~2,1,0,'0@A-~2,1,0,'0@AT~2,1,0,'0@A:~2,1,0,'0@A:~2,1,0,'0@AZ"
              year month date 0 0 0)))
  
  (defun format-readable-decoded-time (&optional (days 0))
    (multiple-value-bind (second minute hour date month year day daylight-p zone) (decode-universal-time (days-ago days))
  
negative.code:                        ((|link| |rel| "alternate" |type| "text/html"
                                  |href| ,(html-escape (format nil "http://sbcl.boinkor.net/bench/?HOST=~A&IMPLEMENTATIONS=~A&ONLY-RELEASE=~A"
                                                  host implementation (release-on-day implementation day)))))
                         (|modified| ,(format-atom-decoded-time day 1))
                         (|issued| ,(format-atom-decoded-time day))
                         (|id| ,(format nil "tag:sbcl.boinkor.net,~A:/bench/~A" (format-readable-decoded-time day) implementation))
                         (|created| ,(format-atom-decoded-time day))
  