diff --git a/lib/WebGUI/Types.pm b/lib/WebGUI/Types.pm
new file mode 100644
index 000000000..6153656a5
--- /dev/null
+++ b/lib/WebGUI/Types.pm
@@ -0,0 +1,20 @@
+package WebGUI::Types;
+
+use Moose;
+use Moose::Util::TypeConstraints;
+
+subtype 'WebGUI::Type::JSONArray'
+    => as 'ArrayRef'
+;
+
+coerce 'WebGUI::Type::JSONArray'
+    => from Str
+    => via  { my $struct = eval { JSON::from_json($_); }; $struct ||= []; return $struct; },
+;
+
+coerce 'WebGUI::Type::JSONArray'
+    => from Undef
+    => via  { return []; },
+;
+
+1;