diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 The MIT License
 
-Copyright (c) 2013-2017 Front Row Education, Inc. www.frontrowed.com
+Copyright (c) 2013-2019 Freckle Education, Inc. www.freckle.com
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/closed.cabal b/closed.cabal
--- a/closed.cabal
+++ b/closed.cabal
@@ -1,23 +1,23 @@
--- This file has been generated from package.yaml by hpack version 0.20.0.
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.31.1.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: e5fbf1e0d45f270ab3829a93b28d76aac53b63b7dc3ff9d76dc0c69309541594
+-- hash: 624ec706a439d32d6323b27102c9ab706d7db6dcb01fd792b513011438f5d796
 
 name:           closed
-version:        0.2.0
+version:        0.2.0.1
 synopsis:       Integers bounded by a closed interval
-description:    Integers bounded by a closed interval
+description:    Integers bounded by a closed interval checked at compile time
 category:       Data
 homepage:       https://github.com/frontrowed/closed#readme
 bug-reports:    https://github.com/frontrowed/closed/issues
-author:         Chris Parks <chris@frontrowed.com>
-maintainer:     Front Row Education <engineering@frontrowed.com>
+author:         Chris Parks <chris@freckle.com>
+maintainer:     Freckle Education <engineering@freckle.com>
 license:        MIT
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.10
-
 extra-source-files:
     README.lhs
 
@@ -26,6 +26,11 @@
   location: https://github.com/frontrowed/closed
 
 library
+  exposed-modules:
+      Closed
+      Closed.Internal
+  other-modules:
+      Paths_closed
   hs-source-dirs:
       library
   build-depends:
@@ -37,30 +42,22 @@
     , hashable
     , persistent
     , text
-  exposed-modules:
-      Closed
-      Closed.Internal
-  other-modules:
-      Paths_closed
   default-language: Haskell2010
 
 test-suite readme
   type: exitcode-stdio-1.0
   main-is: README.lhs
+  other-modules:
+      Paths_closed
   ghc-options: -Wall -pgmL markdown-unlit
   build-depends:
-      QuickCheck
-    , aeson
-    , base
+      aeson
+    , base >=4.9 && <5
     , cassava
     , closed
-    , deepseq
-    , hashable
     , hspec
     , markdown-unlit
     , persistent
     , text
     , vector
-  other-modules:
-      Paths_closed
   default-language: Haskell2010
diff --git a/library/Closed/Internal.hs b/library/Closed/Internal.hs
--- a/library/Closed/Internal.hs
+++ b/library/Closed/Internal.hs
@@ -1,29 +1,39 @@
-{-# LANGUAGE DeriveGeneric #-}
-{-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE ExplicitForAll #-}
+{-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE KindSignatures #-}
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TypeApplications #-}
 {-# LANGUAGE TypeFamilies #-}
 {-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE UndecidableInstances #-}
-{-# LANGUAGE FlexibleContexts #-}
+
+-- Prevent kind errors arising from using * to mean multiplication on
+-- type-level natural numbers.
+#if __GLASGOW_HASKELL__ >= 806
+{-# LANGUAGE NoStarIsType #-}
+#endif
+
 {-# OPTIONS_GHC -fno-warn-unticked-promoted-constructors #-}
+
 module Closed.Internal where
 
 import Control.DeepSeq
 import Control.Monad
 import Data.Aeson
-import Database.Persist.Sql
+import qualified Data.Csv as CSV
 import Data.Hashable
+import Data.Kind (Type)
 import Data.Maybe
 import Data.Proxy
 import Data.Ratio
 import Data.Text (pack)
+import Database.Persist.Sql
 import GHC.Generics
 import GHC.Stack
 import GHC.TypeLits
-import qualified Data.Csv as CSV
 import Test.QuickCheck
 
 newtype Closed (n :: Nat) (m :: Nat)
@@ -40,7 +50,7 @@
 
 -- | Syntactic sugar to express open and half-open intervals using
 -- the 'Closed' type
-type family Bounds (lhs :: Endpoint) (rhs :: Endpoint) :: * where
+type family Bounds (lhs :: Endpoint) (rhs :: Endpoint) :: Type where
   Bounds (Inclusive n) (Inclusive m) = Closed  n       m
   Bounds (Inclusive n) (Exclusive m) = Closed  n      (m - 1)
   Bounds (Exclusive n) (Inclusive m) = Closed (n + 1)  m
@@ -158,7 +168,7 @@
     Closed <$> choose (natVal @n Proxy, natVal @m Proxy)
 
 instance (n <= m, KnownNat n, KnownNat m) => PersistField (Closed n m) where
-  toPersistValue = toPersistValue . (fromIntegral @Integer @Int) . getClosed
+  toPersistValue = toPersistValue . fromIntegral @Integer @Int . getClosed
   fromPersistValue value = do
     x <- fromIntegral @Int @Integer <$> fromPersistValue value
     case closed @n @m x of