diff --git a/Mail/Hailgun/Domains.hs b/Mail/Hailgun/Domains.hs
--- a/Mail/Hailgun/Domains.hs
+++ b/Mail/Hailgun/Domains.hs
@@ -33,6 +33,7 @@
    { hdrTotalCount :: Integer
    , hdrItems      :: [HailgunDomain]
    }
+   deriving (Show)
 
 instance FromJSON HailgunDomainResponse where
    parseJSON (Object v) = HailgunDomainResponse
diff --git a/Mail/Hailgun/Errors.hs b/Mail/Hailgun/Errors.hs
--- a/Mail/Hailgun/Errors.hs
+++ b/Mail/Hailgun/Errors.hs
@@ -18,6 +18,7 @@
 data HailgunErrorResponse = HailgunErrorResponse
    { herMessage :: String -- ^ A generic message describing the error.
    }
+   deriving (Show)
 
 toHailgunError :: String -> HailgunErrorResponse
 toHailgunError = HailgunErrorResponse
diff --git a/Mail/Hailgun/Internal/Data.hs b/Mail/Hailgun/Internal/Data.hs
--- a/Mail/Hailgun/Internal/Data.hs
+++ b/Mail/Hailgun/Internal/Data.hs
@@ -46,6 +46,7 @@
    , hailgunApiKey :: String -- ^ The API key for the mailgun account so that you can successfully make requests. Please note that it should include the 'key' prefix.
    , hailgunProxy  :: Maybe NHC.Proxy
    }
+   deriving (Show)
 
 -- | Any email content that you wish to send should be encoded into these types before it is sent.
 -- Currently, according to the API, you should always send a Text Only part in the email and you can
@@ -68,7 +69,9 @@
       { textContent :: B.ByteString -- ^ The text content that you wish to send (please note that many clients will take the HTML version first if it is present but that the text version is a great fallback).
       , htmlContent :: B.ByteString -- ^ The HTML content that you wish to send.
       }
+   deriving (Show)
 
+
 -- | A Hailgun Email message that may be sent. It contains important information such as the address
 -- that the email is from, the addresses that it should be going to, the subject of the message and
 -- the content of the message. Any email that you wish to send via this api must be converted into
@@ -82,6 +85,7 @@
    , messageBCC         :: [TEV.EmailAddress]
    , messageAttachments :: [SpecificAttachment]
    }
+   deriving (Show)
    -- TODO o:tag support
    -- TODO o:campaign support
    -- messageDKIMSupport :: Bool TODO o:dkim support
@@ -101,17 +105,20 @@
     { attachmentFilePath :: FilePath
     , attachmentBody     :: AttachmentBody
     }
+    deriving (Show)
 
 -- | An Attachment body is the raw data that you want to send with your attachment.
 data AttachmentBody
    = AttachmentBS B.ByteString   -- ^ A strict ByteString representation of your data.
    | AttachmentLBS BL.ByteString -- ^ A lazy ByteString representation of your data.
+   deriving (Show)
 
 data SpecificAttachment = SpecificAttachment
     { saType     :: AttachmentType
     , saFilePath :: FilePath
     , saBody     :: AttachmentBody
     }
+    deriving (Show)
 
 data AttachmentType = Attached | Inline deriving (Eq, Show)
 
@@ -131,6 +138,7 @@
    , recipientsCC  :: [UnverifiedEmailAddress] -- ^ The people to \"Carbon Copy\" into the email. Honestly, why is that term not deprecated yet?
    , recipientsBCC :: [UnverifiedEmailAddress] -- ^ The people to \"Blind Carbon Copy\" into the email. There really needs to be a better name for this too.
    }
+   deriving (Show)
 
 -- The user should just give us a list of attachments and we should automatically make them inline or not
 -- We should consider sending the HTML message as a quoted-string: http://hackage.haskell.org/package/dataenc-0.14.0.5/docs/Codec-Binary-QuotedPrintable.html
@@ -148,4 +156,8 @@
          _      -> fail "could not parse Mailgun Style date"
 
 instance ParseTime HailgunTime where
+#if MIN_VERSION_time(1,6,0)
+   buildTime l input = HailgunTime . zonedTimeToUTC <$> buildTime l input
+#else
    buildTime l = HailgunTime . zonedTimeToUTC . buildTime l
+#endif
diff --git a/Mail/Hailgun/Pagination.hs b/Mail/Hailgun/Pagination.hs
--- a/Mail/Hailgun/Pagination.hs
+++ b/Mail/Hailgun/Pagination.hs
@@ -11,6 +11,7 @@
    { pageStart  :: Integer
    , pageLength :: Integer
    }
+   deriving (Show)
 
 pageToParams :: Page -> [(BC.ByteString, BC.ByteString)]
 pageToParams page =
diff --git a/Mail/Hailgun/SendEmail.hs b/Mail/Hailgun/SendEmail.hs
--- a/Mail/Hailgun/SendEmail.hs
+++ b/Mail/Hailgun/SendEmail.hs
@@ -65,6 +65,7 @@
    { hsrMessage :: String -- ^ The freeform message from the mailgun API.
    , hsrId      :: String -- ^ The ID of the message that has been accepted by the Mailgun api.
    }
+   deriving (Show)
 
 instance FromJSON HailgunSendResponse where
    parseJSON (Object v) = HailgunSendResponse
diff --git a/hailgun.cabal b/hailgun.cabal
--- a/hailgun.cabal
+++ b/hailgun.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.4.0.5
+version:             0.4.1.0
 
 -- A short (one-line) description of the package.
 synopsis:            Mailgun REST api interface for Haskell.
@@ -73,17 +73,17 @@
                         , bytestring         >= 0.10.4 && <= 0.11
                         , aeson              >= 0.8 && < 0.12
                         , text               == 1.2.*
-                        , transformers       >= 0.3 && <0.5
+                        , transformers       >= 0.3 && < 0.6
                         , http-client        == 0.4.*
                         , http-client-tls    == 0.2.*
                         , email-validate     >= 2.0 && <2.3
                         , http-types         >= 0.8 && < 0.10
                         , exceptions         == 0.8.*
-                        , tagsoup            == 0.13.*
+                        , tagsoup            >= 0.13 && < 0.15
                         , filepath           >= 1 && < 2
 
    if flag(newtime)
-      Build-Depends:    time == 1.5.*
+      Build-Depends:    time >= 1.5 && < 1.7
    else
       Build-Depends:    time >= 1.2 && < 1.5, old-locale == 1.*