Count number of quicklisp system dependencies. Results (2025-03): https://gist.github.com/sebastiancarlos/e2e94031f676ddf4bd619cb7f932b6b0

count-quicklisp-dependencies.lisp

; All my gist code is licensed under the MIT license.

(defun count-quicklisp-dependencies ()
  "Count the number of times each system is used as a dependency in Quicklisp."
  (let ((system-list-names (sort (mapcar #'ql-dist::name (ql:system-list)) 
                                 #'string<))
        (file "/tmp/deps.csv"))
    (with-open-file (out file 
                         :direction :output
                         :if-exists :supersede
                         :if-does-not-exist :create)
      (dolist (sys system-list-names)
        (let ((deps (ql:who-depends-on sys)))
          (format out "~A,~A,~{'~A'~^ ~}~%" sys (length deps) deps))))
    (uiop:run-program (format nil "sort -n -r -t, -k2,2 -o ~A ~A" file file))
    (uiop:run-program (format nil "sed -i '1i system,uses,used-by' ~A" file))
    (format nil "Wrote ~A" file)))