diff --git a/squeal-postgresql.cabal b/squeal-postgresql.cabal
--- a/squeal-postgresql.cabal
+++ b/squeal-postgresql.cabal
@@ -1,6 +1,6 @@
 cabal-version: 2.2
 name: squeal-postgresql
-version: 0.9.1.1
+version: 0.9.1.2
 synopsis: Squeal PostgreSQL Library
 description: Squeal is a type-safe embedding of PostgreSQL in Haskell
 homepage: https://github.com/morphismtech/squeal
diff --git a/src/Squeal/PostgreSQL/Session/Oid.hs b/src/Squeal/PostgreSQL/Session/Oid.hs
--- a/src/Squeal/PostgreSQL/Session/Oid.hs
+++ b/src/Squeal/PostgreSQL/Session/Oid.hs
@@ -34,8 +34,9 @@
   , OidOfField (..)
   ) where
 
-import Control.Monad.Catch
-import Control.Monad.Reader
+import Control.Monad (when)
+import Control.Monad.Catch (throwM)
+import Control.Monad.Reader (ReaderT(ReaderT))
 import Data.String
 import GHC.TypeLits
 import PostgreSQL.Binary.Decoding (valueParser, int)