diff --git a/hissmetrics.cabal b/hissmetrics.cabal
--- a/hissmetrics.cabal
+++ b/hissmetrics.cabal
@@ -1,5 +1,5 @@
 Name:                hissmetrics
-Version:             0.3
+Version:             0.4
 Synopsis:            Unofficial API bindings to KISSmetrics.
 Homepage:            https://github.com/meteficha/hissmetrics
 License:             BSD3
@@ -28,9 +28,9 @@
                  , time         >= 1.1     && < 2
                  , bytestring
                  , text         >= 0.7     && < 0.12
-                 , conduit      == 0.4.*
+                 , conduit      == 0.5.*
                  , http-types
-                 , http-conduit == 1.4.*
+                 , http-conduit == 1.5.*
   Extensions:
     DeriveDataTypeable,
     RecordWildCards,
diff --git a/src/Web/KISSmetrics.hs b/src/Web/KISSmetrics.hs
--- a/src/Web/KISSmetrics.hs
+++ b/src/Web/KISSmetrics.hs
@@ -32,14 +32,14 @@
 
 
 -- | Your KISSmetrics API key.
-type APIKey = H.Ascii
+type APIKey = B8.ByteString
 
 
 -- | KISSmetrics names and identities are limited to at most 255
 -- characters and all commas (@,@) and colons (@:@) are changed
 -- to spaces (@ @).  Nothing is checked by this Haskell library,
 -- so be careful =).
-type SimpleText = H.Ascii
+type SimpleText = B8.ByteString
 
 
 -- | A KISSmetrics property.  The property names needs to follow
@@ -183,12 +183,12 @@
     -- KISSmetrics always returns 200 Ok with an invisible 1x1
     -- GIF.  We need to consume the body in order to let the
     -- connection be reused via keep-alive.
-    responseBody C.$$ CL.sinkNull
+    responseBody C.$$+- CL.sinkNull
 
 
 -- | Internal function.  Given a 'CallType', return the URL to be
 -- used and generate a list of arguments.
-callInfo :: CallType -> (H.Ascii, H.SimpleQuery)
+callInfo :: CallType -> (B8.ByteString, H.SimpleQuery)
 callInfo Record {..} =
   ( "/e"
   , (:) ("_n", fromEventName eventName) $