diff --git a/src/Development/IDE/State/Service.hs b/src/Development/IDE/State/Service.hs
index 618a48b3..9cbc6ec0 100644
--- a/src/Development/IDE/State/Service.hs
+++ b/src/Development/IDE/State/Service.hs
@@ -24,7 +24,6 @@ import           Control.Monad.Except
 import Development.IDE.Types.Options (IdeOptions(..))
 import           Development.IDE.State.FileStore
 import qualified Development.IDE.Logger as Logger
-import Data.Maybe
 import           Data.Set                                 (Set)
 import qualified Data.Set                                 as Set
 import           Development.IDE.Functions.GHCError
@@ -70,14 +69,14 @@ unsafeClearDiagnostics = unsafeClearAllDiagnostics
 
 -- | Initialise the Compiler Service.
 initialise :: Rules ()
-           -> Maybe (Event -> IO ())
+           -> (Event -> IO ())
            -> Logger.Handle
            -> IdeOptions
            -> VFSHandle
            -> IO IdeState
 initialise mainRule toDiags logger options vfs =
     shakeOpen
-        (fromMaybe (const $ pure ()) toDiags)
+        toDiags
         logger
         (setProfiling options $
         shakeOptions { shakeThreads = optThreads options
diff --git a/src/Development/IDE/Types/LSP.hs b/src/Development/IDE/Types/LSP.hs
index 9885a7ea..26e45cbd 100644
--- a/src/Development/IDE/Types/LSP.hs
+++ b/src/Development/IDE/Types/LSP.hs
@@ -52,7 +52,4 @@ data Event
     | EventFileValidation Int Int
       -- ^ @EventFileValidation finishedValidations totalValidations @
       -- How many validations have we finished of how many total.
-    | EventFatalError !T.Text
-      -- ^ @EventFatalError reason@: A fatal error occurred in the compiler and
-      -- the compiler cannot continue.
       deriving Show
diff --git a/test/Demo.hs b/test/Demo.hs
index fba5aebd..d11c9c7d 100644
--- a/test/Demo.hs
+++ b/test/Demo.hs
@@ -42,7 +42,7 @@ main = do
     vfs <- makeVFSHandle
     ide <- initialise
         mainRule
-        (Just $ showEvent lock)
+        (showEvent lock)
         (makeOneHandle $ withLock lock . T.putStrLn)
         IdeOptions
             {optPreprocessor = (,) []