diff --git a/os-timer.rkt b/os-timer.rkt
index 3cbd1a1..c2df476 100644
--- a/os-timer.rkt
+++ b/os-timer.rkt
@@ -1,7 +1,6 @@
 #lang racket/base
 
 (require racket/match)
-(require "codec.rkt")
 (require "os-big-bang.rkt")
 (require "os-udp.rkt")