diff --git a/nix/module.nix b/nix/module.nix
index 064283b..dd28b57 100644
--- a/nix/module.nix
+++ b/nix/module.nix
@@ -45,6 +45,11 @@ in {
                   type = types.oneOf [types.port types.str];
                   description = "target port or address inside the namespace";
                 };
+                reverse = mkOption {
+                  type = types.bool;
+                  default = false;
+                  description = "forward from inside the namespace to outside instead";
+                };
               };
             }));
             description = "ports to forward into the namespace";