diff --git a/package/base-files/files/lib/functions.sh b/package/base-files/files/lib/functions.sh
index 851d2f1791..d23a56e0cf 100644
--- a/package/base-files/files/lib/functions.sh
+++ b/package/base-files/files/lib/functions.sh
@@ -45,7 +45,7 @@ prepend() {
 	local value="$2"
 	local sep="${3:- }"
 
-	eval "export ${NO_EXPORT:+-n} -- \"$var=\${$value:+\${$value}\$sep}\$var\""
+	eval "export ${NO_EXPORT:+-n} -- \"$var=\$value\${$var:+\${sep}\${$var}}\""
 }
 
 list_contains() {