diff --git a/extras/scripts/build-single-header.sh b/extras/scripts/build-single-header.sh
index 04d96b4a..d2346b06 100755
--- a/extras/scripts/build-single-header.sh
+++ b/extras/scripts/build-single-header.sh
@@ -55,6 +55,7 @@ process()
 
 simplify_namespaces() {
 	perl -p0i -e 's|\}  // namespace ARDUINOJSON_NAMESPACE\r?\nnamespace ARDUINOJSON_NAMESPACE \{\r?\n||igs' "$1"
+	rm -f "$1.bak"
 }
 
 cd $(dirname $0)/../..