(defvar *dist-urls*
  '("http://dist.shirakumo.org/shirakumo.txt"
    "http://bodge.borodust.org/dist/org.borodust.bodge.txt"
    "http://beta.quicklisp.org/dist/quicklisp.txt"))

(defun dist-installed-from-urlp (url dist)
  "Return T if URL and the url of DIST are the same."
  (string= url (ql-dist::distinfo-subscription-url dist)))

(loop :for url in *dist-urls*
      :unless (find-if (lambda (dist) (dist-installed-from-urlp url dist))
                       (ql-dist:enabled-dists))
      :do (ql-dist:install-dist url :replace t :prompt nil))