diff --git a/hasql-postgres.cabal b/hasql-postgres.cabal
--- a/hasql-postgres.cabal
+++ b/hasql-postgres.cabal
@@ -1,14 +1,15 @@
 name:
   hasql-postgres
 version:
-  0.5.1
+  0.6.0
 synopsis:
   A "PostgreSQL" backend for the "hasql" library
 description:
   This library provides a \"PostgreSQL\" driver for 
   <http://hackage.haskell.org/package/hasql the "hasql" library>.
   .
-  It's tested against Postgres versions 8.3 and 9.3
+  It supports all Postgres versions starting from 8.3 
+  and is tested against 8.3, 9.3 and 9.4
   with the @integer_datetimes@ setting off and on.
   .
   According to the included benchmarks,
@@ -75,17 +76,17 @@
     attoparsec >= 0.10 && < 0.13,
     -- database:
     hasql-backend == 0.1.*,
-    postgresql-binary == 0.3.*,
+    postgresql-binary == 0.5.*,
     postgresql-libpq == 0.9.*,
     -- data:
     uuid == 1.3.*,
     vector == 0.10.*,
     time >= 1.4 && < 1.6,
     hashtables == 1.1.*,
-    scientific == 0.3.*,
+    scientific >= 0.2 && < 0.4,
     text >= 1 && < 1.3,
-    bytestring >= 0.10.4.0 && < 0.11,
-    hashable == 1.2.*,
+    bytestring >= 0.10 && < 0.11,
+    hashable >= 1.1 && < 1.3,
     -- control:
     either == 4.*,
     list-t >= 0.2.3 && < 0.3,
@@ -125,17 +126,17 @@
     attoparsec >= 0.10 && < 0.13,
     -- database:
     hasql >= 0.1.4 && < 0.2,
-    postgresql-binary == 0.3.*,
+    postgresql-binary == 0.5.*,
     postgresql-libpq == 0.9.*,
     -- data:
     uuid == 1.3.*,
     vector == 0.10.*,
     time >= 1.4 && < 1.6,
     hashtables == 1.1.*,
-    scientific == 0.3.*,
+    scientific >= 0.2 && < 0.4,
     text >= 1 && < 1.3,
-    bytestring >= 0.10.4.0 && < 0.11,
-    hashable == 1.2.*,
+    bytestring >= 0.10 && < 0.11,
+    hashable >= 1.1 && < 1.3,
     -- control:
     either == 4.*,
     list-t >= 0.2.3 && < 0.3,
@@ -178,10 +179,10 @@
     vector == 0.10.*,
     old-locale == 1.0.*,
     time >= 1.4 && < 1.6,
-    scientific == 0.3.*,
+    scientific >= 0.2 && < 0.4,
     text >= 1 && < 1.3,
-    bytestring >= 0.10.4.0 && < 0.11,
-    hashable == 1.2.*,
+    bytestring >= 0.10 && < 0.11,
+    hashable >= 1.1 && < 1.3,
     -- general:
     list-t == 0.2.*,
     mtl-prelude < 3,
@@ -221,7 +222,7 @@
     vector == 0.10.*,
     time >= 1.4 && < 1.6,
     text >= 1 && < 1.3,
-    scientific == 0.3.*,
+    scientific >= 0.2 && < 0.4,
     -- general:
     monad-control == 0.3.*,
     deepseq == 1.3.*,
diff --git a/library/Hasql/Postgres/Connector.hs b/library/Hasql/Postgres/Connector.hs
--- a/library/Hasql/Postgres/Connector.hs
+++ b/library/Hasql/Postgres/Connector.hs
@@ -3,7 +3,8 @@
 import Hasql.Postgres.Prelude hiding (Error)
 import qualified Database.PostgreSQL.LibPQ as PQ
 import qualified Data.ByteString as B
-import qualified Data.ByteString.Builder as BB
+import qualified Data.ByteString.Lazy.Builder as BB
+import qualified Data.ByteString.Lazy.Builder.ASCII as BB
 import qualified Data.ByteString.Lazy as BL
 import qualified Data.Text.Encoding as TE
 
@@ -57,13 +58,13 @@
 settingsBS :: Settings -> ByteString
 settingsBS s =
   BL.toStrict $ BB.toLazyByteString $ 
-  mconcat $ intersperse " " args
+  mconcat $ intersperse (BB.char7 ' ') args
   where
     args =
       [
-        "host="     <> BB.byteString (host s),
-        "port="     <> BB.word16Dec (port s),
-        "user="     <> TE.encodeUtf8Builder (user s),
-        "password=" <> TE.encodeUtf8Builder (password s),
-        "dbname="   <> TE.encodeUtf8Builder (database s)
+        BB.string7 "host="     <> BB.byteString (host s),
+        BB.string7 "port="     <> BB.word16Dec (port s),
+        BB.string7 "user="     <> BB.byteString (TE.encodeUtf8 (user s)),
+        BB.string7 "password=" <> BB.byteString (TE.encodeUtf8 (password s)),
+        BB.string7 "dbname="   <> BB.byteString (TE.encodeUtf8 (database s))
       ]
diff --git a/library/Hasql/Postgres/Mapping.hs b/library/Hasql/Postgres/Mapping.hs
--- a/library/Hasql/Postgres/Mapping.hs
+++ b/library/Hasql/Postgres/Mapping.hs
@@ -219,8 +219,8 @@
       (,,,)
         [t|DiffTime|]
         [|PTI.interval|]
-        [|const $ Encoder.interval|]
-        [|const $ Decoder.interval|]
+        [|Encoder.interval|]
+        [|Decoder.interval|]
       ,
       (,,,)
         [t|Char|]
diff --git a/library/Hasql/Postgres/Statement.hs b/library/Hasql/Postgres/Statement.hs
--- a/library/Hasql/Postgres/Statement.hs
+++ b/library/Hasql/Postgres/Statement.hs
@@ -3,7 +3,7 @@
 import Hasql.Postgres.Prelude
 import qualified Database.PostgreSQL.LibPQ as L
 import qualified Data.ByteString as B
-import qualified Data.ByteString.Builder as BB
+import qualified Data.ByteString.Lazy.Builder as BB
 import qualified Data.ByteString.Lazy as BL
 
 
@@ -75,8 +75,8 @@
               Serializable   -> BB.string7 "ISOLATION LEVEL SERIALIZABLE"
             ,
             case w of
-              True  -> "READ WRITE"
-              False -> "READ ONLY"
+              True  -> BB.string7 "READ WRITE"
+              False -> BB.string7 "READ ONLY"
           ]
 
 commitTransaction :: Statement
diff --git a/library/Hasql/Postgres/StatementPreparer.hs b/library/Hasql/Postgres/StatementPreparer.hs
--- a/library/Hasql/Postgres/StatementPreparer.hs
+++ b/library/Hasql/Postgres/StatementPreparer.hs
@@ -8,7 +8,8 @@
 import qualified Hasql.Postgres.ResultParser as Result
 import qualified Hasql.Postgres.ResultHandler as ResultHandler
 import qualified Data.ByteString as B
-import qualified Data.ByteString.Builder as BB
+import qualified Data.ByteString.Lazy.Builder as BB
+import qualified Data.ByteString.Lazy.Builder.ASCII as BB
 import qualified Data.ByteString.Lazy as BL
 
 
diff --git a/library/Hasql/Postgres/TemplateConverter.hs b/library/Hasql/Postgres/TemplateConverter.hs
--- a/library/Hasql/Postgres/TemplateConverter.hs
+++ b/library/Hasql/Postgres/TemplateConverter.hs
@@ -2,7 +2,8 @@
 
 import Hasql.Postgres.Prelude
 import qualified Data.ByteString.Lazy as BL
-import qualified Data.ByteString.Builder as BB
+import qualified Data.ByteString.Lazy.Builder as BB
+import qualified Data.ByteString.Lazy.Builder.ASCII as BB
 import qualified Hasql.Postgres.TemplateConverter.Parser as Parser
 
 
diff --git a/library/Hasql/Postgres/TemplateConverter/Parser.hs b/library/Hasql/Postgres/TemplateConverter/Parser.hs
--- a/library/Hasql/Postgres/TemplateConverter/Parser.hs
+++ b/library/Hasql/Postgres/TemplateConverter/Parser.hs
@@ -3,7 +3,7 @@
 import Hasql.Postgres.Prelude
 import Data.Attoparsec.ByteString.Char8
 import qualified Data.ByteString.Lazy as BL
-import qualified Data.ByteString.Builder as BB
+import qualified Data.ByteString.Lazy.Builder as BB
 
 
 data Part =
