anchor.diff:  (export-always '*supported-managers*)
   (defvar *supported-managers* '()
     "The list of supported manager class symbols.")
  -
  -;; TODO: What would be an ideal default location?
  -(defvar profile-directory (uiop:xdg-data-home "profiles"))
  -(defvar manifest-directory (uiop:xdg-data-home "manifests"))
   
   (defun manager-found-p (class-sym)
     "Prepend the CLASS-SYM instance to `*detected-managers*' if NAME is an
  
positive.code: 
  (define-class manager ()
    ((path ""
           :type (or string pathname)))
    (:export-class-name-p t)
    (:export-accessor-names-p t)
    (:accessor-name-transformer (hu.dwim.defclass-star:make-name-transformer name)))
  
  (define-class os-package ()
    ((name "")
  
negative.code:   (manager-list-manifests (manager)))
  
  (defmethod manager-list-manifests ((manager manager))
    (uiop:directory-files (uiop:ensure-directory-pathname (manifest-directory manager))))
  
  (export-always 'list-generations)
  (defun list-generations (&optional profile)
  