anchor.diff:  
   (defun make-request-buffer (host port path &key (method "GET"))
     (setf method (string method))
  -  (when *proxy-url*
  -    (setf path (full-proxy-path host port path)))
  -  (let ((sink (make-instance 'octet-sink)))
  -    (flet ((add-line (&rest strings)
  -             (apply #'add-strings sink strings)
  -             (add-newline sink)))
  -      (add-line method " " path " HTTP/1.1")
  -      (add-line "Host: " host (if (= port 80) ""
  -                                  (format nil ":~D" port)))
  -      (when (and *proxy-url* *proxy-user* *proxy-pass*)
  -        (add-line "Proxy-Authorization: Basic " (make-basic-authentication *proxy-user* *proxy-pass*)))
  -      (add-line "Connection: close")
  -      ;; FIXME: get this version string from somewhere else.
  -      (add-line "User-Agent: quicklisp-bootstrap/"
  -                qlqs-info:*version*)
  -      (add-newline sink)
  -      (sink-buffer sink))))
  +  (let ((proxy-user nil)
  +        (proxy-pass nil))
  +    (when *proxy-url*
  +      (setf path (full-proxy-path host port path))
  +      (when (need-proxyauthenticate-p *proxy-url*)
  +        (let ((proxy (parse-urlstring *proxy-url* :proxy-auth t)))
  +          (setf proxy-user (proxy-user proxy))
  +          (setf proxy-pass (proxy-pass proxy)))))
  +    (let ((sink (make-instance 'octet-sink)))
  +      (flet ((add-line (&rest strings)
  +               (apply #'add-strings sink strings)
  +               (add-newline sink)))
  +        (add-line method " " path " HTTP/1.1")
  +        (add-line "Host: " host (if (= port 80) ""
  +                                    (format nil ":~D" port)))
  +        (when (and proxy-user proxy-pass)
  +          (add-line "Proxy-Authorization: Basic " (make-basic-authentication proxy-user proxy-pass)))
  +        (add-line "Connection: close")
  +        ;; FIXME: get this version string from somewhere else.
  +        (add-line "User-Agent: quicklisp-bootstrap/"
  +                  qlqs-info:*version*)
  +        (add-newline sink)
  +        (sink-buffer sink)))))
   
   (defun sink-until-matching (matcher cbuf)
     (let ((sink (make-instance 'octet-sink)))
  
positive.code:                   dist-url
                    dist-version)
    (setf *home* (merge-pathnames *home* (truename *default-pathname-defaults*)))
    (when *proxy-url*
      (setf *proxy* (parse-urlstring *proxy-url* :proxy-auth (need-proxyauthenticate-p *proxy-url*)))
      (setf *proxy-server* (proxyurlstring *proxy*))
      (setf *proxy-user* (proxy-user *proxy*))
      (setf *proxy-pass* (proxy-pass *proxy*)))
    (let ((name (non-empty-file-namestring *home*)))
      (when name
        (warn "Making ~A part of the install pathname directory"
  
negative.code:   (subseq (storage sink) 0))
  
  (defvar *proxy-url* nil)
  
  (defun full-proxy-path (host port path)
    (format nil "~:[http~;https~]://~A~:[:~D~;~*~]~A"
  