diff --git a/lib/librt/Makefile b/lib/librt/Makefile
index 8b880c41ec4..2c8eb1400fb 100644
--- a/lib/librt/Makefile
+++ b/lib/librt/Makefile
@@ -3,7 +3,7 @@
 
 PACKAGE=clibs
 LIB=rt
-SHLIBDIR=/lib
+SHLIBDIR?=/lib
 SHLIB_MAJOR= 1
 CFLAGS+=-I${SRCTOP}/lib/libc/include -I${.CURDIR}
 .ifndef NO_THREAD_STACK_UNWIND