diff --git a/fpco-api.cabal b/fpco-api.cabal
--- a/fpco-api.cabal
+++ b/fpco-api.cabal
@@ -1,5 +1,5 @@
 name:                 fpco-api
-version:              1.1.1.2
+version:              1.1.1.3
 synopsis:             Simple interface to the FP Complete IDE API.
 description:          A server and library for communicating with the FP Complete IDE API.
 homepage:             https://www.fpcomplete.com/page/api
diff --git a/src/library/FP/API/Types.hs b/src/library/FP/API/Types.hs
--- a/src/library/FP/API/Types.hs
+++ b/src/library/FP/API/Types.hs
@@ -547,7 +547,7 @@
     deriving (Eq, Show, Data, Read, Typeable, PersistField, Random, Num)
 
 instance PersistFieldSql TutorialConcurrentToken where
-    sqlType _ = sqlType (Nothing :: Maybe Int)
+    sqlType _ = sqlType (Proxy :: Proxy Int)
 
 instance Default TutorialConcurrentToken where
     def = TutorialConcurrentToken' 1