diff --git a/src/Calculi/Lambda/Cube/TH.hs b/src/Calculi/Lambda/Cube/TH.hs
--- a/src/Calculi/Lambda/Cube/TH.hs
+++ b/src/Calculi/Lambda/Cube/TH.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 module Calculi.Lambda.Cube.TH (
      -- sfo
       sf
@@ -11,12 +12,17 @@
 import qualified Compiler.Typesystem.SystemF as SF
 import qualified Compiler.Typesystem.SimplyTyped as STLC
 import Text.Megaparsec
+import Text.Megaparsec.Error
 import Calculi.Lambda.Cube
 import Data.List
 import Control.Monad
 
 -- | Lambda Cube parsec type.
+#if __GLASGOW_HASKELL__ >= 800
+type LCParsec = Parsec Dec String
+#else
 type LCParsec = Parsec String
+#endif
 -- | SystemFOmega with mono and poly types represented as strings.
 -- type StringSFO = SFO.SystemFOmega String String (Maybe (STLC.SimplyTyped String))
 -- | SystemF with mono and poly types represented as strings.
diff --git a/src/Compiler/Typesystem/Hask.hs b/src/Compiler/Typesystem/Hask.hs
deleted file mode 100644
--- a/src/Compiler/Typesystem/Hask.hs
+++ /dev/null
@@ -1,52 +0,0 @@
-{-|
-    Re-export of the type expression AST exposed by TemplateHaskell with instances
-    of `SimpleType`, `HigherOrder`, and `Polymorphic`.
--}
-module Compiler.Typesystem.Hask (
-      Type(..)
-    , Name(..)
-) where
-
-import Language.Haskell.TH.Syntax as TH (Type(..), Name(..), TyVarBndr(..))
-import Calculi.Lambda.Cube.HigherOrder
-import Calculi.Lambda.Cube.Polymorphic
-import Calculi.Lambda.Cube.SimpleType
-import Control.Typecheckable
-import qualified Data.Set as Set
-import Data.Semigroup
-
-instance SimpleType Type where
-
-    type MonoType Type = Name
-
-    abstract a b = (ArrowT `AppT` a) `AppT` b
-
-    reify ((ArrowT `AppT` a) `AppT` b) = Just (a, b)
-    reify _ = Nothing
-
-    mono = ConT
-
-    bases = \case
-        ForallT binds _ texpr -> bases texpr
-        AppT arg ret          -> bases arg <> bases ret
-        SigT texpr _          -> bases texpr
-        a                     -> Set.singleton a
-
-    equivalent = areAlphaEquivalent
-
-instance Polymorphic Type where
-
-    type PolyType Type = Name
-
-    substitutions = curry $ \case
-        (ForallT _ _ texpr1, texpr2)             -> substitutions texpr1 texpr2
-        (texpr1            , ForallT _ _ texpr2) -> substitutions texpr1 texpr2
-        (SigT texpr1 _     , texpr2)             -> substitutions texpr1 texpr2
-        (texpr1            , SigT texpr2 _)      -> substitutions texpr1 texpr2
-        (VarT v1           , VarT v2)            -> Right [Mutual v1 v2]
-        (VarT v            , texpr)              -> Right [Substitution texpr v]
-        (texpr             , VarT v)             -> Right [Substitution texpr v]
-        (AppT arg1 ret1    , AppT arg2 ret2)     -> substitutions arg1 arg2 <><> substitutions ret1 ret2
-        (texpr1            , texpr2)
-            | texpr1 == texpr2 -> Right []
-            | otherwise        -> Left [(texpr1, texpr2)]
diff --git a/src/Control/Typecheckable.hs b/src/Control/Typecheckable.hs
--- a/src/Control/Typecheckable.hs
+++ b/src/Control/Typecheckable.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE FlexibleContexts #-}
 {-|
diff --git a/typerbole.cabal b/typerbole.cabal
--- a/typerbole.cabal
+++ b/typerbole.cabal
@@ -1,5 +1,5 @@
 name:                typerbole
-version:             0.0.0.4
+version:             0.0.0.5
 synopsis:            A typeystems library with exaggerated claims
 description:         Please see README.md
 license:             BSD3
@@ -36,13 +36,12 @@
                      , Calculi.Lambda.Cube.HigherOrder
                      , Calculi.Lambda.Cube.Dependent
                      , Calculi.Lambda.Cube.TH
-                     , Compiler.Typesystem.Hask
                      , Compiler.Typesystem.SystemF
                      , Compiler.Typesystem.SystemFOmega
                      , Compiler.Typesystem.SimplyTyped
                      , Control.Typecheckable
                      , Data.Graph.Inductive.Helper
-  build-depends:       base >= 4.7 && < 4.9
+  build-depends:       base >= 4.7 && < 5
                      , containers >= 0.5 && < 0.6
                      , data-ordlist
                      , either
@@ -54,9 +53,9 @@
                      , mtl
                      , generic-random == 0.1.1.0
                      , lens
-                     , template-haskell < 2.11
-                     , th-lift >= 0.7 && < 0.8
-                     , megaparsec < 5
+                     , template-haskell
+                     , th-lift
+                     , megaparsec
                      , safe
   ghc-options:         -Wall
                        -fno-warn-type-defaults