diff --git a/pagerduty.cabal b/pagerduty.cabal
--- a/pagerduty.cabal
+++ b/pagerduty.cabal
@@ -1,5 +1,5 @@
 name:                  pagerduty
-version:               0.0.7
+version:               0.0.8
 synopsis:              Client library for PagerDuty Integration and REST APIs.
 homepage:              http://github.com/brendanhay/pagerduty
 license:               OtherLicense
@@ -72,7 +72,7 @@
 
     build-depends:
         aeson                 >= 0.8
-      , base                  >= 4.7      && < 5
+      , base                  >= 4.7 && < 5
       , bifunctors            >= 4.1
       , bytestring            >= 0.9
       , bytestring-conversion >= 0.2.1
@@ -80,7 +80,7 @@
       , data-default-class    >= 0.0.1
       , exceptions            >= 0.6
       , generics-sop          >= 0.2.0.0
-      , http-client           >= 0.4.3
+      , http-client           >= 0.5 && < 1
       , http-types            >= 0.8
       , lens                  >= 4.4
       , lens-aeson            >= 1
diff --git a/src/Control/Monad/Trans/PagerDuty.hs b/src/Control/Monad/Trans/PagerDuty.hs
--- a/src/Control/Monad/Trans/PagerDuty.hs
+++ b/src/Control/Monad/Trans/PagerDuty.hs
@@ -44,7 +44,7 @@
 import           Control.Applicative
 import           Control.Monad.Base
 import           Control.Monad.Catch
-import           Control.Monad.Error              (MonadError (..))
+import           Control.Monad.Except             (MonadError (..))
 import           Control.Monad.Morph
 import           Control.Monad.Reader
 import           Control.Monad.Trans.Control
diff --git a/src/Network/PagerDuty/Integration.hs b/src/Network/PagerDuty/Integration.hs
--- a/src/Network/PagerDuty/Integration.hs
+++ b/src/Network/PagerDuty/Integration.hs
@@ -81,7 +81,6 @@
 import           Control.Lens
 import           Control.Monad.IO.Class
 import           Data.Aeson
-import           Data.Default.Class
 import qualified Data.HashMap.Strict              as Map
 import           Data.Text                        (Text)
 import           Network.HTTP.Client              (Manager)
@@ -292,7 +291,8 @@
            -> Event
            -> m (Either Error Response)
 submitWith m l e = request m l e $
-    def { Client.host   = "events.pagerduty.com"
+    Client.defaultRequest
+        { Client.host   = "events.pagerduty.com"
         , Client.path   = "/generic/2010-04-15/create_event.json"
         , Client.method = "POST"
         }
diff --git a/src/Network/PagerDuty/REST.hs b/src/Network/PagerDuty/REST.hs
--- a/src/Network/PagerDuty/REST.hs
+++ b/src/Network/PagerDuty/REST.hs
@@ -29,7 +29,6 @@
 import           Control.Monad.Trans
 import           Data.Aeson                       (FromJSON)
 import           Data.Conduit
-import           Data.Default.Class
 import           Data.Monoid
 import           Network.HTTP.Client              (Manager)
 import qualified Network.HTTP.Client              as Client
@@ -90,7 +89,7 @@
     }
   where
    raw = case e ^. envAuth of
-        AuthBasic u p -> Client.applyBasicAuth u p def
-        AuthToken t   -> def
+        AuthBasic u p -> Client.applyBasicAuth u p Client.defaultRequest
+        AuthToken t   -> Client.defaultRequest
             { Client.requestHeaders = [("Authorization", "Token token=" <> t)]
             }