diff --git a/README.md b/README.md
index 479cc5d..2f0ec55 100644
--- a/README.md
+++ b/README.md
@@ -206,7 +206,7 @@ Your Elm program needs:
 
   ```elm
   type alias Model =
-      { tasks : ConcurrentTask.Pool Msg Error Success
+      { tasks : ConcurrentTask.Pool Msg
       }
   ```
 
@@ -214,7 +214,7 @@ Your Elm program needs:
 
   ```elm
   type Msg
-      = OnProgress ( ConcurrentTask.Pool Msg Error Success, Cmd Msg ) -- updates task progress
+      = OnProgress ( ConcurrentTask.Pool Msg, Cmd Msg ) -- updates task progress
       | OnComplete (ConcurrentTask.Response Error Success) -- called when a task completes
   ```
 
@@ -236,12 +236,12 @@ import Json.Decode as Decode
 
 
 type alias Model =
-    { tasks : ConcurrentTask.Pool Msg Error Titles
+    { tasks : ConcurrentTask.Pool Msg
     }
 
 
 type Msg
-    = OnProgress ( ConcurrentTask.Pool Msg Error Titles, Cmd Msg )
+    = OnProgress ( ConcurrentTask.Pool Msg, Cmd Msg )
     | OnComplete (ConcurrentTask.Response Error Titles)
 
 
diff --git a/examples/dom-operations/src/Main.elm b/examples/dom-operations/src/Main.elm
index cee98be..8dc2103 100644
--- a/examples/dom-operations/src/Main.elm
+++ b/examples/dom-operations/src/Main.elm
@@ -57,7 +57,7 @@ type alias Flags =
 
 
 type alias Pool =
-    ConcurrentTask.Pool Msg Error Output
+    ConcurrentTask.Pool Msg
 
 
 type alias Error =
diff --git a/examples/fruits-pipeline-worker/src/Main.elm b/examples/fruits-pipeline-worker/src/Main.elm
index 93583ca..9f6aca3 100644
--- a/examples/fruits-pipeline-worker/src/Main.elm
+++ b/examples/fruits-pipeline-worker/src/Main.elm
@@ -51,7 +51,7 @@ type Msg
 
 
 type alias Pool =
-    Task.Pool Msg Error Output
+    Task.Pool Msg
 
 
 type Error
diff --git a/examples/localstorage-fruit-trees/src/Main.elm b/examples/localstorage-fruit-trees/src/Main.elm
index b1b35c3..c9e9cd9 100644
--- a/examples/localstorage-fruit-trees/src/Main.elm
+++ b/examples/localstorage-fruit-trees/src/Main.elm
@@ -75,7 +75,7 @@ updatePears n fruits =
 
 
 type alias Pool =
-    ConcurrentTask.Pool Msg Error Output
+    ConcurrentTask.Pool Msg
 
 
 type alias Error =
diff --git a/examples/many-requests/src/Main.elm b/examples/many-requests/src/Main.elm
index 6c294d9..e5e922f 100644
--- a/examples/many-requests/src/Main.elm
+++ b/examples/many-requests/src/Main.elm
@@ -3,7 +3,7 @@ port module Main exposing (main)
 import ConcurrentTask as Task exposing (ConcurrentTask)
 import ConcurrentTask.Http as Http
 import ConcurrentTask.Process
-import Json.Decode as Decode exposing (Decoder)
+import Json.Decode as Decode
 
 
 {-| Many Requests
@@ -37,7 +37,7 @@ type Msg
 
 
 type alias Pool =
-    Task.Pool Msg Error Output
+    Task.Pool Msg
 
 
 type alias Error =
diff --git a/examples/spa-example/src/Pages/Home_.elm b/examples/spa-example/src/Pages/Home_.elm
index 6ebf4e9..a72b5cc 100644
--- a/examples/spa-example/src/Pages/Home_.elm
+++ b/examples/spa-example/src/Pages/Home_.elm
@@ -84,7 +84,7 @@ getTodo id =
 
 
 type alias Pool =
-    ConcurrentTask.Pool Msg Error Output
+    ConcurrentTask.Pool Msg
 
 
 type alias Error =
diff --git a/examples/spa-example/src/Pages/Posts.elm b/examples/spa-example/src/Pages/Posts.elm
index 11e8405..13b8eaf 100644
--- a/examples/spa-example/src/Pages/Posts.elm
+++ b/examples/spa-example/src/Pages/Posts.elm
@@ -89,7 +89,7 @@ getPost id =
 
 
 type alias Pool =
-    ConcurrentTask.Pool Msg Error Output
+    ConcurrentTask.Pool Msg
 
 
 type alias Error =
diff --git a/examples/spa-example/src/Spa/ConcurrentTask.elm b/examples/spa-example/src/Spa/ConcurrentTask.elm
index cc8ad3a..aacab16 100644
--- a/examples/spa-example/src/Spa/ConcurrentTask.elm
+++ b/examples/spa-example/src/Spa/ConcurrentTask.elm
@@ -6,8 +6,8 @@ import Json.Decode as Decode
 
 
 subscriptions :
-    (( ConcurrentTask.Pool msg x a, Cmd msg ) -> msg)
-    -> { model | tasks : ConcurrentTask.Pool msg x a }
+    (( ConcurrentTask.Pool msg, Cmd msg ) -> msg)
+    -> { model | tasks : ConcurrentTask.Pool msg }
     -> Sub msg
 subscriptions onProgress { tasks } =
     ConcurrentTask.onProgress
@@ -30,10 +30,10 @@ progress model ( tasks, cmd ) =
 
 attempt :
     { task : ConcurrentTask x a
-    , pool : ConcurrentTask.Pool msg x a
+    , pool : ConcurrentTask.Pool msg
     , onComplete : ConcurrentTask.Response x a -> msg
     }
-    -> ( ConcurrentTask.Pool msg x a, Cmd msg )
+    -> ( ConcurrentTask.Pool msg, Cmd msg )
 attempt { task, pool, onComplete } =
     ConcurrentTask.attempt
         { send = send
diff --git a/integration/src/Integration/Runner.elm b/integration/src/Integration/Runner.elm
index 65cbb5b..097829a 100644
--- a/integration/src/Integration/Runner.elm
+++ b/integration/src/Integration/Runner.elm
@@ -35,7 +35,7 @@ type Msg
 
 
 type alias Pool =
-    Task.Pool Msg Error Output
+    Task.Pool Msg
 
 
 type alias Error =
diff --git a/src/ConcurrentTask.elm b/src/ConcurrentTask.elm
index e67267e..759f2dd 100644
--- a/src/ConcurrentTask.elm
+++ b/src/ConcurrentTask.elm
@@ -132,11 +132,11 @@ Here's a minimal complete example:
     import Json.Decode as Decode
 
     type alias Model =
-        { tasks : ConcurrentTask.Pool Msg Http.Error Titles
+        { tasks : ConcurrentTask.Pool Msg
         }
 
     type Msg
-        = OnProgress ( ConcurrentTask.Pool Msg Http.Error Titles, Cmd Msg )
+        = OnProgress ( ConcurrentTask.Pool Msg, Cmd Msg )
         | OnComplete (ConcurrentTask.Response Http.Error Titles)
 
     init : ( Model, Cmd Msg )
@@ -882,18 +882,42 @@ Make sure to update your `Model` and pass in the `Cmd` returned from `attempt`.
 
 -}
 attempt :
-    { pool : Pool msg x a
+    { pool : Pool msg
     , send : Decode.Value -> Cmd msg
     , onComplete : Response x a -> msg
     }
     -> ConcurrentTask x a
-    -> ( Pool msg x a, Cmd msg )
-attempt options =
+    -> ( Pool msg, Cmd msg )
+attempt config task =
+    let
+        mappedTask : ConcurrentTask msg msg
+        mappedTask =
+            task
+                |> map (\res -> config.onComplete (Success res))
+                |> onError
+                    (\err ->
+                        config.onComplete (Error err)
+                            |> succeed
+                    )
+
+        onComplete : Internal.Response msg msg -> msg
+        onComplete res =
+            case res of
+                Internal.Success s ->
+                    s
+
+                Internal.Error e ->
+                    e
+
+                Internal.UnexpectedError e ->
+                    config.onComplete (UnexpectedError (toUnexpectedError e))
+    in
     Internal.attempt
-        { pool = options.pool
-        , send = options.send
-        , onComplete = toResponse >> options.onComplete
+        { pool = config.pool
+        , send = config.send
+        , onComplete = onComplete
         }
+        mappedTask
 
 
 {-| The value returned from a task when it completes (returned in the `OnComplete` msg).
@@ -939,19 +963,6 @@ type UnexpectedError
     | InternalError String
 
 
-toResponse : Internal.Response x a -> Response x a
-toResponse res =
-    case res of
-        Internal.Success a ->
-            Success a
-
-        Internal.Error x ->
-            Error x
-
-        Internal.UnexpectedError e ->
-            UnexpectedError (toUnexpectedError e)
-
-
 toUnexpectedError : Internal.UnexpectedError -> UnexpectedError
 toUnexpectedError err =
     case err of
@@ -1000,9 +1011,9 @@ Make sure to update your `Model` and pass in the `Cmd` in your `OnProgress` bran
 onProgress :
     { send : Decode.Value -> Cmd msg
     , receive : (Decode.Value -> msg) -> Sub msg
-    , onProgress : ( Pool msg x a, Cmd msg ) -> msg
+    , onProgress : ( Pool msg, Cmd msg ) -> msg
     }
-    -> Pool msg x a
+    -> Pool msg
     -> Sub msg
 onProgress =
     Internal.onProgress
@@ -1011,8 +1022,8 @@ onProgress =
 {-| A Pool keeps track of each task's progress,
 and allows multiple Task attempts to be in-flight at the same time.
 -}
-type alias Pool msg x a =
-    Internal.Pool msg x a
+type alias Pool msg =
+    Internal.Pool msg
 
 
 {-| Create an empty ConcurrentTask Pool.
@@ -1024,6 +1035,6 @@ Right now it doesn't expose any functionality, but it could be used in the futur
   - Expose metrics on previous or running tasks.
 
 -}
-pool : Pool msg x a
+pool : Pool msg
 pool =
     Internal.pool
diff --git a/src/ConcurrentTask/Internal/ConcurrentTask.elm b/src/ConcurrentTask/Internal/ConcurrentTask.elm
index 5a9054f..530bc0a 100644
--- a/src/ConcurrentTask/Internal/ConcurrentTask.elm
+++ b/src/ConcurrentTask/Internal/ConcurrentTask.elm
@@ -562,14 +562,14 @@ mapResponseError f res =
 -- Execute a Task
 
 
-type Pool msg x a
-    = Pool (Pool_ msg x a)
+type Pool msg
+    = Pool (Pool_ msg)
 
 
-type alias Pool_ msg x a =
+type alias Pool_ msg =
     { poolId : PoolId
-    , queued : List ( Array Todo, Progress msg x a )
-    , attempts : Dict AttemptId (Progress msg x a)
+    , queued : List ( Array Todo, Progress msg )
+    , attempts : Dict AttemptId (Progress msg)
     , attemptIds : Ids
     }
 
@@ -595,10 +595,10 @@ type PoolId
     | Identified String
 
 
-type alias Progress msg x a =
+type alias Progress msg =
     { inFlight : Set TaskId
-    , task : ( Ids, ConcurrentTask x a )
-    , onComplete : Response x a -> msg
+    , task : ( Ids, ConcurrentTask msg msg )
+    , onComplete : Response msg msg -> msg
     }
 
 
@@ -617,21 +617,21 @@ type alias AttemptId =
     Ids.Id
 
 
-type alias Attempt msg x a =
-    { pool : Pool msg x a
+type alias Attempt msg =
+    { pool : Pool msg
     , send : Decode.Value -> Cmd msg
-    , onComplete : Response x a -> msg
+    , onComplete : Response msg msg -> msg
     }
 
 
-type alias OnProgress msg x a =
+type alias OnProgress msg =
     { send : Decode.Value -> Cmd msg
     , receive : (Decode.Value -> msg) -> Sub msg
-    , onProgress : ( Pool msg x a, Cmd msg ) -> msg
+    , onProgress : ( Pool msg, Cmd msg ) -> msg
     }
 
 
-attempt : Attempt msg x a -> ConcurrentTask x a -> ( Pool msg x a, Cmd msg )
+attempt : Attempt msg -> ConcurrentTask msg msg -> ( Pool msg, Cmd msg )
 attempt attempt_ task =
     case stepTask Dict.empty ( Ids.init, task ) of
         ( _, Done res ) ->
@@ -641,7 +641,7 @@ attempt attempt_ task =
 
         ( _, Pending defs _ ) ->
             let
-                progress : Progress msg x a
+                progress : Progress msg
                 progress =
                     { task = ( Ids.init, task )
                     , inFlight = recordSent defs Set.empty
@@ -669,12 +669,12 @@ attempt attempt_ task =
 
 
 startTask :
-    { progress : Progress msg x a
-    , pool : Pool msg x a
+    { progress : Progress msg
+    , pool : Pool msg
     , send : Encode.Value -> Cmd msg
     , defs : Array Todo
     }
-    -> ( Pool msg x a, Cmd msg )
+    -> ( Pool msg, Cmd msg )
 startTask options =
     ( startAttempt options.progress options.pool
     , options.send (encodeDefinitions (currentAttemptId options.pool) options.defs)
@@ -694,7 +694,7 @@ decodeIdentifyResponse =
         )
 
 
-onProgress : OnProgress msg x a -> Pool msg x a -> Sub msg
+onProgress : OnProgress msg -> Pool msg -> Sub msg
 onProgress options pool_ =
     options.receive
         (\rawResults ->
@@ -726,7 +726,7 @@ onProgress options pool_ =
         )
 
 
-startQueuedTasks : { send : Encode.Value -> Cmd msg, pool : Pool msg x a } -> ( Pool msg x a, Cmd msg )
+startQueuedTasks : { send : Encode.Value -> Cmd msg, pool : Pool msg } -> ( Pool msg, Cmd msg )
 startQueuedTasks options =
     queuedTasks options.pool
         |> List.foldl
@@ -743,12 +743,12 @@ startQueuedTasks options =
         |> Tuple.mapFirst clearQueue
 
 
-updateAttempt : OnProgress msg x a -> Pool msg x a -> ( AttemptId, Results ) -> Progress msg x a -> ( Pool msg x a, Cmd msg )
+updateAttempt : OnProgress msg -> Pool msg -> ( AttemptId, Results ) -> Progress msg -> ( Pool msg, Cmd msg )
 updateAttempt options pool_ ( attemptId, results ) progress =
     case stepTask results progress.task of
         ( ids_, Pending _ next_ ) ->
             let
-                nextProgress : ( Ids, ConcurrentTask x a )
+                nextProgress : ( Ids, ConcurrentTask msg msg )
                 nextProgress =
                     ( ids_, next_ )
             in
@@ -800,7 +800,7 @@ sendResult onComplete res =
     CoreTask.succeed res |> CoreTask.perform onComplete
 
 
-notStarted : Progress msg x a -> Todo -> Bool
+notStarted : Progress msg -> Todo -> Bool
 notStarted model def =
     not (Set.member def.taskId model.inFlight)
 
@@ -994,7 +994,7 @@ encodeDefinition attemptId def =
 -- Pool
 
 
-pool : Pool msg x a
+pool : Pool msg
 pool =
     Pool
         { poolId = Unidentified
@@ -1004,7 +1004,7 @@ pool =
         }
 
 
-startAttempt : Progress msg x a -> Pool msg x a -> Pool msg x a
+startAttempt : Progress msg -> Pool msg -> Pool msg
 startAttempt progress p =
     mapPool
         (\pool_ ->
@@ -1016,7 +1016,7 @@ startAttempt progress p =
         p
 
 
-currentAttemptId : Pool msg x a -> AttemptId
+currentAttemptId : Pool msg -> AttemptId
 currentAttemptId (Pool pool_) =
     case pool_.poolId of
         Identified id ->
@@ -1029,47 +1029,47 @@ currentAttemptId (Pool pool_) =
             Ids.get pool_.attemptIds
 
 
-poolId : Pool msg x a -> PoolId
+poolId : Pool msg -> PoolId
 poolId (Pool pool_) =
     pool_.poolId
 
 
-withPoolId : PoolId -> Pool msg x a -> Pool msg x a
+withPoolId : PoolId -> Pool msg -> Pool msg
 withPoolId id =
     mapPool (\pool_ -> { pool_ | poolId = id })
 
 
-queueTask : ( Array Todo, Progress msg x a ) -> Pool msg x a -> Pool msg x a
+queueTask : ( Array Todo, Progress msg ) -> Pool msg -> Pool msg
 queueTask progress =
     mapPool (\pool_ -> { pool_ | queued = progress :: pool_.queued })
 
 
-updateProgressFor : AttemptId -> Progress msg x a -> Pool msg x a -> Pool msg x a
+updateProgressFor : AttemptId -> Progress msg -> Pool msg -> Pool msg
 updateProgressFor attemptId progress_ =
     mapPool (\pool_ -> { pool_ | attempts = Dict.update attemptId (Maybe.map (always progress_)) pool_.attempts })
 
 
-removeFromPool : AttemptId -> Pool msg x a -> Pool msg x a
+removeFromPool : AttemptId -> Pool msg -> Pool msg
 removeFromPool attemptId =
     mapPool (\pool_ -> { pool_ | attempts = Dict.remove attemptId pool_.attempts })
 
 
-queuedTasks : Pool msg x a -> List ( Array Todo, Progress msg x a )
+queuedTasks : Pool msg -> List ( Array Todo, Progress msg )
 queuedTasks (Pool p) =
     p.queued
 
 
-clearQueue : Pool msg x a -> Pool msg x a
+clearQueue : Pool msg -> Pool msg
 clearQueue =
     mapPool (\pool_ -> { pool_ | queued = [] })
 
 
-findAttempt : AttemptId -> Pool msg x a -> Maybe (Progress msg x a)
+findAttempt : AttemptId -> Pool msg -> Maybe (Progress msg)
 findAttempt attemptId (Pool p) =
     Dict.get attemptId p.attempts
 
 
-mapPool : (Pool_ msg x a -> Pool_ msg x a) -> Pool msg x a -> Pool msg x a
+mapPool : (Pool_ msg -> Pool_ msg) -> Pool msg -> Pool msg
 mapPool f (Pool p) =
     Pool (f p)