diff --git a/subprojects/wrapper-manager-fds/modules/wrapper-manager/base.nix b/subprojects/wrapper-manager-fds/modules/wrapper-manager/base.nix
index 7b63a87a..9079b543 100644
--- a/subprojects/wrapper-manager-fds/modules/wrapper-manager/base.nix
+++ b/subprojects/wrapper-manager-fds/modules/wrapper-manager/base.nix
@@ -8,7 +8,7 @@
 let
   envConfig = config;
 
-  toStringType = with lib.types; coercedTo str (x: "${x}") str;
+  toStringType = with lib.types; coercedTo (oneOf [str path int float bool]) (x: "${x}") str;
   envSubmodule =
     {
       config,