diff --git a/pkgs/applications/office/fava/default.nix b/pkgs/applications/office/fava/default.nix
index a5de74a6f16..6b26870ee44 100644
--- a/pkgs/applications/office/fava/default.nix
+++ b/pkgs/applications/office/fava/default.nix
@@ -25,6 +25,7 @@ buildPythonApplication rec {
       markdown2
       ply
       simplejson
+      jaraco_functools
     ];
 
   # CLI test expects fava on $PATH.  Not sure why static_url fails.