diff --git a/make/lib.sh b/make/lib.sh
index 20329d3f..727df395 100644
--- a/make/lib.sh
+++ b/make/lib.sh
@@ -36,8 +36,8 @@ function gimli_only {
 }
 
 function only_in_directory {
-	DIR="$1"
-	CURRENT="$(readlink -f .)"
+	local DIR="$1"
+	local CURRENT="$(readlink -f .)"
 	if test "$CURRENT" != "$DIR"
 	then
 		echo "Tento příkaz se má spouštět ve složce $DIR, chceš pokračovat? Pokud ne, sestřel tento skript."
@@ -52,8 +52,8 @@ function safe_checkout_branch {
 		return 1
 	fi
 
-	BRANCH="$1"
-	SCRIPT="$2"
+	local BRANCH="$1"
+	local SCRIPT="$2"
 
 	echo "Debug: I am $0, $SCRIPT as param"