diff --git a/nixos/modules/virtualisation/libvirtd.nix b/nixos/modules/virtualisation/libvirtd.nix
index 583b09192e3..6d36fd4caa0 100644
--- a/nixos/modules/virtualisation/libvirtd.nix
+++ b/nixos/modules/virtualisation/libvirtd.nix
@@ -24,6 +24,7 @@ in
 
     virtualisation.libvirtd.enable =
       mkOption {
+        type = types.bool;
         default = false;
         description =
           ''
@@ -36,6 +37,7 @@ in
 
     virtualisation.libvirtd.enableKVM =
       mkOption {
+        type = types.bool;
         default = true;
         description =
           ''
@@ -45,6 +47,7 @@ in
 
     virtualisation.libvirtd.extraConfig =
       mkOption {
+        type = types.lines;
         default = "";
         description =
           ''