diff --git a/Makefile b/Makefile
index 688a88d7..7775a841 100644
--- a/Makefile
+++ b/Makefile
@@ -94,7 +94,7 @@ build:
 	$S grep -r -L 'Note: this file is built non-deterministically' _site/ \
 	  | egrep -v 'sha256sums.txt' \
 	  | sort \
-	  | xargs sha256sum > _site/sha256sums.txt
+	  | xargs -d '\n' sha256sum > _site/sha256sums.txt
 
 ## Jekyll annoyingly returns success even when it emits errors and
 ## exceptions, so we'll grep its output for error strings