Add cabal.project to build with the correct flags

src/Language/GraphQL/Foundation.hs

@@ -0,0 +1,5 @@
+module Language.GraphQL.Foundation
+    ( module Language.GraphQL.Serialize
+    ) where
+
+import Language.GraphQL.Serialize

src/Language/GraphQL/Serialize.hs

@@ -0,0 +1,7 @@
+module Language.GraphQL.Serialize
+    ( JSON(..)
+    ) where
+
+import qualified Data.Aeson as Aeson
+
+newtype JSON = JSON Aeson.Value