diff --git a/parameter/boolean b/parameter/boolean
new file mode 100644
index 0000000..5c7edf0
--- /dev/null
+++ b/parameter/boolean
@@ -0,0 +1 @@
+config-from-stdin
diff --git a/parameter/optional b/parameter/optional
index 2dba30a..04204c7 100644
--- a/parameter/optional
+++ b/parameter/optional
@@ -1,2 +1 @@
 config
-config-from-stdin