diff --git a/extra/mason/common/common.factor b/extra/mason/common/common.factor
index bc1b182734..a33e3c5831 100755
--- a/extra/mason/common/common.factor
+++ b/extra/mason/common/common.factor
@@ -79,8 +79,8 @@ SYMBOL: stamp
     with-directory ;
 
 : git-id ( -- id )
-    { "git" "show" } utf8 [ readln ] with-process-reader
-    " " split second ;
+    { "git" "show" } utf8 [ lines ] with-process-reader
+    first " " split second ;
 
 : ?prepare-build-machine ( -- )
     builds/factor exists? [ prepare-build-machine ] unless ;