diff --git a/jbuild b/jbuild
new file mode 100644
index 00000000..0947b360
--- /dev/null
+++ b/jbuild
@@ -0,0 +1 @@
+(jbuilder_version 1)
diff --git a/vendor/cmdliner/src/jbuild b/vendor/cmdliner/src/jbuild
index 3472cf77..ab3d9c80 100644
--- a/vendor/cmdliner/src/jbuild
+++ b/vendor/cmdliner/src/jbuild
@@ -1,5 +1,5 @@
 (library
  ((name        jbuilder_cmdliner)
   (public_name jbuilder.cmdliner)
-  (extra_disabled_warnings (3 6 27 32 33 35 50))
+  (flags (-w -3-6-27-32-33-35-50))
   (preprocess  no_preprocessing)))