diff --git a/selda-postgresql.cabal b/selda-postgresql.cabal
--- a/selda-postgresql.cabal
+++ b/selda-postgresql.cabal
@@ -1,5 +1,5 @@
 name:                selda-postgresql
-version:             0.1.7.0
+version:             0.1.7.1
 synopsis:            PostgreSQL backend for the Selda database EDSL.
 description:         PostgreSQL backend for the Selda database EDSL.
                      Requires the PostgreSQL @libpq@ development libraries to be
@@ -31,7 +31,7 @@
       base       >=4.8      && <5
     , bytestring >=0.9      && <0.11
     , exceptions >=0.8      && <0.9
-    , selda      >=0.1.10.0 && <0.2
+    , selda      >=0.1.12   && <0.2
     , text       >=1.0      && <1.3
   if !flag(haste)
     build-depends:
diff --git a/src/Database/Selda/PostgreSQL.hs b/src/Database/Selda/PostgreSQL.hs
--- a/src/Database/Selda/PostgreSQL.hs
+++ b/src/Database/Selda/PostgreSQL.hs
@@ -110,7 +110,7 @@
     case st of
       ConnectionOk -> do
         let backend = pgBackend conn
-        liftIO $ runStmt backend "SET client_min_messages TO WARNING;" []
+        _ <- liftIO $ runStmt backend "SET client_min_messages TO WARNING;" []
         newConnection backend (decodeUtf8 connStr)
       nope -> do
         connFailed nope
@@ -130,6 +130,7 @@
   , backendId       = PostgreSQL
   , ppConfig        = defPPConfig
     { ppType = pgColType defPPConfig
+    , ppTypePK = pgColTypePK defPPConfig
     , ppAutoIncInsert = "DEFAULT"
     , ppColAttrs = ppColAttrs defPPConfig . filter (/= AutoIncrement)
     }
@@ -223,10 +224,15 @@
 
 -- | Custom column types for postgres.
 pgColType :: PPConfig -> SqlTypeRep -> T.Text
-pgColType _ TRowID    = "BIGSERIAL"
+pgColType _ TRowID    = "BIGINT"
 pgColType _ TInt      = "INT8"
 pgColType _ TFloat    = "FLOAT8"
 pgColType _ TDateTime = "TIMESTAMP"
 pgColType _ TBlob     = "BYTEA"
 pgColType cfg t       = ppType cfg t
+
+-- | Custom column types (primary key position) for postgres.
+pgColTypePK :: PPConfig -> SqlTypeRep -> T.Text
+pgColTypePK _ TRowID    = "BIGSERIAL"
+pgColTypePK cfg t       = pgColType cfg t
 #endif
diff --git a/src/Database/Selda/PostgreSQL/Encoding.hs b/src/Database/Selda/PostgreSQL/Encoding.hs
--- a/src/Database/Selda/PostgreSQL/Encoding.hs
+++ b/src/Database/Selda/PostgreSQL/Encoding.hs
@@ -14,7 +14,6 @@
 
 #else
 
-import Control.Exception (throw)
 import qualified Data.ByteString as BS
 import Data.ByteString.Builder
 import Data.ByteString.Char8 (unpack)
@@ -79,13 +78,13 @@
       | otherwise =
         error $ "bad blob string from postgres: " ++ show s
       where
-        hex n s =
-          case BS.index s n of
+        hex n x =
+          case BS.index x n of
             c | c >= 97   -> c - 87 -- c >= 'a'
               | c >= 65   -> c - 55 -- c >= 'A'
               | otherwise -> c - 48 -- c is numeric
-        go s
-          | BS.length s >= 2 = (16*hex 0 s + (hex 1 s)) : go (BS.drop 2 s)
+        go x
+          | BS.length x >= 2 = (16*hex 0 x + (hex 1 x)) : go (BS.drop 2 x)
           | otherwise        = []
     textish = [textType, timestampType, timeType, dateType]
     readBool "f"     = False