diff --git a/nixos/modules/config/shells-environment.nix b/nixos/modules/config/shells-environment.nix
index a0a20228a7422..676828b659bc0 100644
--- a/nixos/modules/config/shells-environment.nix
+++ b/nixos/modules/config/shells-environment.nix
@@ -42,7 +42,7 @@ in
         strings.  The latter is concatenated, interspersed with colon
         characters.
       '';
-      type = with types; attrsOf (either str (listOf str));
+      type = with types; lazyAttrsOf (either str (listOf str));
       apply = mapAttrs (n: v: if isList v then concatStringsSep ":" v else v);
     };