diff --git a/modules/radix/services/linux.scm b/modules/radix/services/linux.scm
index c9496a4..1693734 100644
--- a/modules/radix/services/linux.scm
+++ b/modules/radix/services/linux.scm
@@ -57,7 +57,7 @@
   (plain-file "thinkfan.conf"
     "options thinkpad_acpi experimental=1 fan_control=1"))
 
-(define thinkfan-modprobe-etc-service
+(define (thinkfan-modprobe-etc-service config)
   `(("modprobe.d/thinkfan.conf" ,thinkfan-modprobe-config)))
 
 (define thinkfan-service-type