anchor.diff:                      :multi-selection-p t)))
       (%describe-os-package packages)))
   
  +(defun viewable-file-type-p (path)
  +  (let ((path-suffix (string-downcase (namestring path))))
  +    (some (lambda (suffix)
  +            (str:ends-with? path-suffix suffix) )
  +          '(".html" ".htm") )))
  +
  +;; TODO: open in editor, with select program, leverage file-manager
  +(define-command list-os-package-files ()
  +  "List files of select packages."
  +  (let* ((packages-or-outputs (if (typep (ospama:manager) 'ospama:guix-manager)
  +                                  (prompt-minibuffer
  +                                   :suggestion-function (os-package-output-suggestion-filter)
  +                                   :input-prompt "List files of OS package outputs(s)"
  +                                   :multi-selection-p t)
  +                                  (prompt-minibuffer
  +                                   :suggestion-function (os-package-suggestion-filter)
  +                                   :input-prompt "List files of OS package(s)"
  +                                   :multi-selection-p t)))
  +         (buffer (or (find-buffer 'os-package-manager-mode)
  +                     (nyxt/os-package-manager-mode:os-package-manager-mode
  +                      :activate t
  +                      :buffer (make-internal-buffer :title "*OS packages*"))))
  +         (content
  +           (markup:markup
  +            (:style (style buffer))
  +            (:h1 "Package files")
  +            (:ul
  +             (loop for package-or-output in packages-or-outputs
  +                   collect (markup:markup*
  +                            `(:li ,(object-string package-or-output)
  +                                  (:ul
  +                                   ,@(mapcar (lambda (file)
  +                                               `(:li ,(if (viewable-file-type-p file)
  +                                                          `(:a :href ,file ,file)
  +                                                          file)))
  +                                             (ospama:list-files (list package-or-output))))))))))
  +         (insert-content (ps:ps (setf (ps:@ document body |innerHTML|)
  +                                      (ps:lisp content)))))
  +    (ffi-buffer-evaluate-javascript-async buffer insert-content)
  +    (set-current-buffer buffer)
  +    buffer))
  +
   (defun format-command-stream (process-info callback)
     (loop for object = (read-line (uiop:process-info-output process-info) nil :eof)
           until (eq object :eof)
  
positive.code: 
  ;; TODO: Parse Texinfo for Guix descriptions.
  ;; TODO: Add commands:
  ;; - find-files (open in editor, with select program) -- leverage file-manager
  ;; - show-deps, show-reverse-deps (when minibuffer has actions)
  
negative.code:           (make-string (max 1 (- 40 (length (ospama:name pkg)))) :initial-element #\ )
            (ospama:synopsis pkg)))
  
  (defmethod object-string ((output ospama:os-package-output))
    (format nil "~a:~a"
            (ospama:name (ospama:parent-package output))
            (ospama:name output)))
  (defmethod object-display ((output ospama:os-package-output))
    (let ((pkg (ospama:parent-package output)))
      (format nil "~a:~a~a~a"
              (ospama:name pkg)
              (ospama:name output)
              (make-string (max 1 (- 40 (length (ospama:name pkg)))) :initial-element #\ )
              (ospama:synopsis pkg))))
  
  (defun os-package-suggestion-filter ()
    (echo "Loading package database...")
    (let* ((all-packages (ospama:list-packages)))
      (echo "")
      (lambda (minibuffer)
        (fuzzy-match (input-buffer minibuffer) all-packages))))
  
  (defun os-package-output-suggestion-filter ()
    (echo "Loading package database...")
    (let* ((all-outputs (ospama:list-package-outputs)))
      (echo "")
      (lambda (minibuffer)
        (fuzzy-match (input-buffer minibuffer) all-outputs))))
  
  (defun os-installed-package-suggestion-filter (profile)
    (let* ((installed-packages (ospama:list-packages profile)))
  