diff --git a/Language/Haskell/GhcMod/Browse.hs b/Language/Haskell/GhcMod/Browse.hs
index d651d0c..76801a4 100644
--- a/Language/Haskell/GhcMod/Browse.hs
+++ b/Language/Haskell/GhcMod/Browse.hs
@@ -53,7 +53,6 @@ browse opt cradle mdlName = do
     fallback e                = throwGhcException e
     loadAndFind = do
       setTargetFiles [mdlName]
-      checkSlowAndSet
       void $ load LoadAllTargets
       findModule mdlname Nothing
 
diff --git a/Language/Haskell/GhcMod/Check.hs b/Language/Haskell/GhcMod/Check.hs
index c9f585c..5854059 100644
--- a/Language/Haskell/GhcMod/Check.hs
+++ b/Language/Haskell/GhcMod/Check.hs
@@ -39,7 +39,6 @@ check opt cradle fileNames = checkIt `gcatch` handleErrMsg ls
     checkIt = do
         (readLog,_) <- initializeFlagsWithCradle opt cradle options True
         setTargetFiles fileNames
-        checkSlowAndSet
         void $ load LoadAllTargets
         liftIO readLog
     options
diff --git a/Language/Haskell/GhcMod/Debug.hs b/Language/Haskell/GhcMod/Debug.hs
index 7666695..f325b36 100644
--- a/Language/Haskell/GhcMod/Debug.hs
+++ b/Language/Haskell/GhcMod/Debug.hs
@@ -32,17 +32,14 @@ debug opt cradle fileName = do
             liftIO (fromCabalFile ||> return simpleCompilerOption)
           else
             return simpleCompilerOption
-    [fast] <- do
-        void $ initializeFlagsWithCradle opt cradle gopts True
-        setTargetFiles [fileName]
-        pure . canCheckFast <$> depanal [] False
+    void $ initializeFlagsWithCradle opt cradle gopts True
+    setTargetFiles [fileName]
     return [
         "Current directory:   " ++ currentDir
       , "Cabal file:          " ++ cabalFile
       , "GHC options:         " ++ unwords gopts
       , "Include directories: " ++ unwords incDir
       , "Dependent packages:  " ++ (intercalate ", " $ map fst pkgs)
-      , "Fast check:          " ++ if fast then "Yes" else "No"
       ]
   where
     currentDir = cradleCurrentDir cradle
diff --git a/Language/Haskell/GhcMod/GHCApi.hs b/Language/Haskell/GhcMod/GHCApi.hs
index 00a7d74..dad5823 100644
--- a/Language/Haskell/GhcMod/GHCApi.hs
+++ b/Language/Haskell/GhcMod/GHCApi.hs
@@ -7,9 +7,6 @@ module Language.Haskell.GhcMod.GHCApi (
   , initializeFlagsWithCradle
   , setTargetFiles
   , getDynamicFlags
-  , setSlowDynFlags
-  , checkSlowAndSet
-  , canCheckFast
   ) where
 
 import Control.Applicative
@@ -121,7 +118,10 @@ modifyFlags d0 idirs depPkgs splice build
   | otherwise = d4
   where
     d1 = d0 { importPaths = idirs }
-    d2 = setFastOrNot d1 Fast
+    d2 = d1 {
+        ghcLink   = LinkInMemory
+      , hscTarget = HscInterpreted
+      }
     d3 = Gap.addDevPkgs d2 depPkgs
     d4 | build == CabalPkg = Gap.setCabalPkg d3
        | otherwise         = d3
@@ -131,31 +131,6 @@ setSplice dflag = dopt_set dflag Opt_D_dump_splices
 
 ----------------------------------------------------------------
 
-setFastOrNot :: DynFlags -> CheckSpeed -> DynFlags
-setFastOrNot dflags Slow = dflags {
-    ghcLink   = LinkInMemory
-  , hscTarget = HscInterpreted
-  }
-setFastOrNot dflags Fast = dflags {
-    ghcLink   = NoLink
-  , hscTarget = HscNothing
-  }
-
-setSlowDynFlags :: GhcMonad m => m ()
-setSlowDynFlags = (flip setFastOrNot Slow <$> getSessionDynFlags)
-                  >>= void . setSessionDynFlags
-
--- | To check TH, a session module graph is necessary.
--- "load" sets a session module graph using "depanal".
--- But we have to set "-fno-code" to DynFlags before "load".
--- So, this is necessary redundancy.
-checkSlowAndSet :: GhcMonad m => m ()
-checkSlowAndSet = do
-    fast <- canCheckFast <$> depanal [] False
-    unless fast setSlowDynFlags
-
-----------------------------------------------------------------
-
 modifyFlagsWithOpts :: GhcMonad m => DynFlags -> [GHCOption] -> m DynFlags
 modifyFlagsWithOpts dflags cmdOpts =
     tfst <$> parseDynamicFlags dflags (map noLoc cmdOpts)
@@ -176,11 +151,3 @@ setTargetFiles files = do
 -- | Return the 'DynFlags' currently in use in the GHC session.
 getDynamicFlags :: IO DynFlags
 getDynamicFlags = runGhc (Just libdir) getSessionDynFlags
-
--- | Checking if Template Haskell or quasi quotes are used.
---   If not, the process can be faster.
-canCheckFast :: ModuleGraph -> Bool
-canCheckFast = not . any (hasTHorQQ . ms_hspp_opts)
-  where
-    hasTHorQQ :: DynFlags -> Bool
-    hasTHorQQ dflags = any (`xopt` dflags) [Opt_TemplateHaskell, Opt_QuasiQuotes]
diff --git a/Language/Haskell/GhcMod/Info.hs b/Language/Haskell/GhcMod/Info.hs
index a45e13d..9fc93a6 100644
--- a/Language/Haskell/GhcMod/Info.hs
+++ b/Language/Haskell/GhcMod/Info.hs
@@ -10,7 +10,7 @@ module Language.Haskell.GhcMod.Info (
   ) where
 
 import Control.Applicative ((<$>))
-import Control.Monad (void, when)
+import Control.Monad (void)
 import CoreUtils (exprType)
 import Data.Function (on)
 import Data.Generics hiding (typeOf)
@@ -135,20 +135,17 @@ pretty dflag = showUnqualifiedOneLine dflag . Gap.typeForUser
 ----------------------------------------------------------------
 
 inModuleContext :: Cmd -> Options -> Cradle -> FilePath -> ModuleString -> Ghc String -> String -> Ghc String
-inModuleContext cmd opt cradle file modstr action errmsg =
+inModuleContext _ opt cradle file modstr action errmsg =
     valid ||> invalid ||> return errmsg
   where
     valid = do
         void $ initializeFlagsWithCradle opt cradle ["-w:"] False
-        when (cmd == Info) setSlowDynFlags
         setTargetFiles [file]
-        checkSlowAndSet
         void $ load LoadAllTargets
         doif setContextFromTarget action
     invalid = do
         void $ initializeFlagsWithCradle opt cradle ["-w:"] False
         setTargetBuffer
-        checkSlowAndSet
         void $ load LoadAllTargets
         doif setContextFromTarget action
     setTargetBuffer = do
diff --git a/Language/Haskell/GhcMod/Internal.hs b/Language/Haskell/GhcMod/Internal.hs
index 68ed070..fbeda09 100644
--- a/Language/Haskell/GhcMod/Internal.hs
+++ b/Language/Haskell/GhcMod/Internal.hs
@@ -14,8 +14,6 @@ module Language.Haskell.GhcMod.Internal (
   , cabalDependPackages
   , cabalSourceDirs
   , cabalAllTargets
-  -- * GHC API
-  , canCheckFast
   -- * Getting 'DynFlags'
   , getDynamicFlags
   -- * Initializing 'DynFlags'
@@ -23,7 +21,6 @@ module Language.Haskell.GhcMod.Internal (
   , initializeFlagsWithCradle
   -- * 'GhcMonad'
   , setTargetFiles
-  , checkSlowAndSet
   -- * 'Ghc' Choice
   , (||>)
   , goNext
diff --git a/Language/Haskell/GhcMod/Types.hs b/Language/Haskell/GhcMod/Types.hs
index d8a55b0..e6dcebc 100644
--- a/Language/Haskell/GhcMod/Types.hs
+++ b/Language/Haskell/GhcMod/Types.hs
@@ -113,8 +113,6 @@ type Expression = String
 -- | Module name.
 type ModuleString = String
 
-data CheckSpeed = Slow | Fast
-
 -- | Option information for GHC
 data CompilerOptions = CompilerOptions {
     ghcOptions  :: [GHCOption]  -- ^ Command line options
diff --git a/ghc-mod.cabal b/ghc-mod.cabal
index 03d1ce2..d436f32 100644
--- a/ghc-mod.cabal
+++ b/ghc-mod.cabal
@@ -111,7 +111,6 @@ Test-Suite spec
                         BrowseSpec
                         CabalApiSpec
                         CheckSpec
-                        DebugSpec
                         FlagSpec
                         InfoSpec
                         LangSpec
diff --git a/test/DebugSpec.hs b/test/DebugSpec.hs
deleted file mode 100644
index a97325d..0000000
--- a/test/DebugSpec.hs
+++ /dev/null
@@ -1,23 +0,0 @@
-module DebugSpec where
-
-import Language.Haskell.GhcMod
-import Test.Hspec
-
-import Dir
-
-checkFast :: String -> String -> IO ()
-checkFast file ans = withDirectory_ "test/data" $ do
-    let cradle = Cradle "." Nothing Nothing [] []
-    res <- debugInfo defaultOptions cradle file
-    lines res `shouldContain` [ans]
-
-spec :: Spec
-spec = do
-    describe "debug" $ do
-        it "can check TH" $ do
-            checkFast "Main.hs" "Fast check:          No"
-            checkFast "Foo.hs"  "Fast check:          Yes"
-            checkFast "Bar.hs"  "Fast check:          No"
-
-        it "can check QuasiQuotes" $ do
-            checkFast "Baz.hs"  "Fast check:          No"