diff --git a/Database/Persist/Postgresql.hs b/Database/Persist/Postgresql.hs
--- a/Database/Persist/Postgresql.hs
+++ b/Database/Persist/Postgresql.hs
@@ -186,8 +186,8 @@
     pullS (ret, rowRef, rowCount, getters) = do
         row <- atomicModifyIORef rowRef (\r -> (r+1, r))
         if row == rowCount
-           then return C.Closed
-           else fmap C.Open $ forM (zip getters [0..]) $ \(getter, col) -> do
+           then return C.IOClosed
+           else fmap C.IOOpen $ forM (zip getters [0..]) $ \(getter, col) -> do
                                 mbs <- LibPQ.getvalue' ret row col
                                 case mbs of
                                   Nothing -> return PersistNull
@@ -208,10 +208,8 @@
     render (P (PersistTimeOfDay t))   = PG.render t
     render (P (PersistUTCTime t))     = PG.render t
     render (P PersistNull)            = PG.render PG.Null
-    render (P (PersistList _))        =
-        error "Refusing to serialize a PersistList to a PostgreSQL value"
-    render (P (PersistMap _))         =
-        error "Refusing to serialize a PersistMap to a PostgreSQL value"
+    render (P (PersistList l))        = PG.render $ listToJSON l
+    render (P (PersistMap m))         = PG.render $ mapToJSON m
     render (P (PersistObjectId _))    =
         error "Refusing to serialize a PersistObjectId to a PostgreSQL value"
 
@@ -373,7 +371,7 @@
                 Right t -> do
                     let cname = DBName x
                     ref <- getRef cname
-                    return $ Right $ Column cname (y == "YES") t d'' ref
+                    return $ Right $ Column cname (y == "YES") t d'' Nothing ref
   where
     getRef cname = do
         let sql = pack $ concat
@@ -410,10 +408,10 @@
     return $ Left $ pack $ "Invalid result from information_schema: " ++ show x
 
 findAlters :: Column -> [Column] -> ([AlterColumn'], [Column])
-findAlters col@(Column name isNull type_ def ref) cols =
+findAlters col@(Column name isNull type_ def _maxLen ref) cols =
     case filter (\c -> cName c == name) cols of
         [] -> ([(name, Add col)], cols)
-        Column _ isNull' type_' def' ref':_ ->
+        Column _ isNull' type_' def' _maxLen' ref':_ ->
             let refDrop Nothing = []
                 refDrop (Just (_, cname)) = [(name, DropReference cname)]
                 refAdd Nothing = []
@@ -441,7 +439,7 @@
                  filter (\c -> cName c /= name) cols)
 
 showColumn :: Column -> String
-showColumn (Column n nu t def ref) = concat
+showColumn (Column n nu t def _maxLen ref) = concat
     [ T.unpack $ escape n
     , " "
     , showSqlType t
diff --git a/persistent-postgresql.cabal b/persistent-postgresql.cabal
--- a/persistent-postgresql.cabal
+++ b/persistent-postgresql.cabal
@@ -1,8 +1,8 @@
 name:            persistent-postgresql
-version:         0.7.0
+version:         0.8.0
 license:         BSD3
 license-file:    LICENSE
-author:          Michael Snoyman <michael@snoyman.com>
+author:          Felipe Lessa, Michael Snoyman <michael@snoyman.com>
 maintainer:      Michael Snoyman <michael@snoyman.com>
 synopsis:        Backend for the persistent library using postgresql.
 description:     Based on the postgresql-simple package
@@ -17,14 +17,14 @@
                    , transformers          >= 0.2.1    && < 0.3
                    , postgresql-simple     >= 0.0.3    && < 0.1
                    , postgresql-libpq      >= 0.6.1    && < 0.7
-                   , persistent            >= 0.7      && < 0.8
+                   , persistent            >= 0.8      && < 0.9
                    , containers            >= 0.2
                    , bytestring            >= 0.9      && < 0.10
                    , text                  >= 0.7      && < 0.12
                    , monad-control         >= 0.2      && < 0.4
                    , time                  >= 1.1
                    , aeson                 >= 0.5
-                   , conduit
+                   , conduit               >= 0.2
     exposed-modules: Database.Persist.Postgresql
     ghc-options:     -Wall