diff --git a/flake.nix b/flake.nix
index a9db76b..81ab8c7 100644
--- a/flake.nix
+++ b/flake.nix
@@ -41,8 +41,13 @@
       }: {
         options.services.wanireminder = {
           enable = lib.mkEnableOption "wanikani reminder bot";
+          calendarTimes = lib.mkOption {
+            type = lib.types.oneOf [(lib.type.listOf lib.types.str) lib.types.str];
+            default = "hourly";
+            description = "Systemd timer specification";
+          };
           webhook = lib.mkOption {
-            type = lib.types.string;
+            type = lib.types.str;
             description = "The webhook to post the messages to";
           };
           users =
@@ -51,13 +56,13 @@
             }
             // {
               name = lib.mkOption {
-                type = lib.types.string;
+                type = lib.types.str;
               };
               wktoken = lib.mkOption {
-                type = lib.types.string;
+                type = lib.types.str;
               };
               discord = lib.mkOption {
-                type = lib.types.string;
+                type = lib.types.str;
               };
             };
         };
@@ -66,7 +71,7 @@
             wantedBy = [ "timers.target" ];
             after = ["network.target"];
             timerConfig = {
-              OnCalendar = "hourly";
+              OnCalendar = config.services.wanireminder.calendarTimes;
               Persistent = true;
               Unit = ["wanireminder.service"];
             };