diff --git a/nixos/modules/services/misc/cpuminer-cryptonight.nix b/nixos/modules/services/misc/cpuminer-cryptonight.nix
index adaee2bbb215..a06077497e22 100644
--- a/nixos/modules/services/misc/cpuminer-cryptonight.nix
+++ b/nixos/modules/services/misc/cpuminer-cryptonight.nix
@@ -43,7 +43,7 @@ in
         description = "Password for mining server";
       };
       threads = lib.mkOption {
-        type = lib.types.int;
+        type = lib.types.ints.unsigned;
         default = 0;
         description = "Number of miner threads, defaults to available processors";
       };