diff --git a/src/jtk/timer.d b/src/jtk/timer.d
index 41cd95e..df053dc 100644
--- a/src/jtk/timer.d
+++ b/src/jtk/timer.d
@@ -7,9 +7,9 @@ class Timer
 {
     private static Timer[Timer] timers;
 
-    ulong next;
+    private ulong next;
 
-    ulong interval;
+    private ulong interval;
 
     void * user;