diff --git a/dhall-json/src/Dhall/JSONToDhall.hs b/dhall-json/src/Dhall/JSONToDhall.hs
index 960911a60..8573d6a3d 100644
--- a/dhall-json/src/Dhall/JSONToDhall.hs
+++ b/dhall-json/src/Dhall/JSONToDhall.hs
@@ -344,6 +344,7 @@ module Dhall.JSONToDhall (
       parseConversion
     , Conversion(..)
     , defaultConversion
+    , UnionConv(..)
     , resolveSchemaExpr
     , typeCheckSchemaExpr
     , dhallFromJSON