diff --git a/.local/share/common-lisp/source/ambrevar/file.lisp b/.local/share/common-lisp/source/ambrevar/file.lisp
index bba00bcd..07971626 100644
--- a/.local/share/common-lisp/source/ambrevar/file.lisp
+++ b/.local/share/common-lisp/source/ambrevar/file.lisp
@@ -9,6 +9,9 @@
   (trivial-package-local-nicknames:add-package-local-nickname :alex :alexandria)
   (trivial-package-local-nicknames:add-package-local-nickname :sera :serapeum))
 
+;; TODO: Allow some slots to modify file on disk.  Transaction?
+;; Could we edit files virtually nonetheless?  Does that even make sense?
+
 (sera:eval-always
   (defun name-identity (name definition)
     (declare (ignore definition))
@@ -230,3 +233,29 @@ See `%description'."
 (defun finder+mime (root &rest predicates)
   (let ((*finder-constructor* #'file+mime))
     (apply #'finder root predicates)))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defclass* mediafile (file+mime)        ; REVIEW: Include MIME?
+    ((media-format nil
+                   :type (or null ambrevar/ffprobe:media-format))
+     (media-streams '()
+                    :type (or null
+                              (cons ambrevar/ffprobe:media-stream))))
+    (:accessor-name-transformer #'name-identity))
+
+(defmethod initialize-instance :after ((file mediafile) &key)
+  (let ((probe (ambrevar/ffprobe:ffprobe (path file))))
+    (setf (media-format file) (first probe)
+          (media-streams file) (rest probe))))
+
+(defun mediafile (path)
+  (make-instance 'mediafile :path path))
+
+(defun mediawalk (root &rest predicates)
+  (let ((*finder-constructor* #'mediafile))
+    (apply #'walk root predicates)))
+
+(defun mediafinder (root &rest predicates)
+  (let ((*finder-constructor* #'mediafile))
+    (apply #'finder root predicates)))