diff --git a/syndicate/drivers/filesystem.rkt b/syndicate/drivers/filesystem.rkt
index c102796..56f1595 100644
--- a/syndicate/drivers/filesystem.rkt
+++ b/syndicate/drivers/filesystem.rkt
@@ -72,7 +72,9 @@
                                     (lambda (_dummy)
                                       ;; (log-info "track-file-changes ~v: directory changed" name)
                                       (ground-send! (inbound (file-container-changed parent-path)))
-                                      (loop))))))))
+                                      (loop))))))
+            (signal-background-activity! -1)))
+  (signal-background-activity! +1)
   (on-stop (channel-put control-ch 'quit)))
 
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