diff --git a/extra/mason/platform/platform.factor b/extra/mason/platform/platform.factor
index 59c525f5ea..d6be8654c5 100644
--- a/extra/mason/platform/platform.factor
+++ b/extra/mason/platform/platform.factor
@@ -1,11 +1,14 @@
 ! Copyright (C) 2008 Eduardo Cavazos, Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: kernel system accessors namespaces splitting sequences
-mason.config bootstrap.image ;
+mason.config bootstrap.image assocs ;
 IN: mason.platform
 
+: (platform) ( os cpu -- string )
+    { { CHAR: . CHAR: - } } substitute "-" glue ;
+
 : platform ( -- string )
-    target-os get "-" target-cpu get "." split "-" join 3append ;
+    target-os get target-cpu get (platform) ;
 
 : gnu-make ( -- string )
     target-os get { "freebsd" "openbsd" "netbsd" } member? "gmake" "make" ? ;