diff --git a/README.md b/README.md
index cd75e07..4ee7cee 100644
--- a/README.md
+++ b/README.md
@@ -40,3 +40,6 @@ Note that `fibonacciSlow` has been modified to call the faster `fibonacci` funct
 
 The `memoize` function can be applied whenever there is a `Tabulate` instance for the function argument type. This library provides instances of the `Tabulate` type class for common types, such as `Maybe`, `Either` and `Tuple`.
 
+## Related resources
+
+- Slides: [Elegant memoization](https://github.com/conal/talk-2014-elegant-memoization/blob/master/README.md) by Conal Elliott - @conal
diff --git a/bower.json b/bower.json
index 4c81a80..1628f49 100644
--- a/bower.json
+++ b/bower.json
@@ -15,19 +15,16 @@
   },
   "license": "MIT",
   "dependencies": {
-    "purescript-lazy": "^3.0.0",
-    "purescript-either": "^3.0.0",
-    "purescript-maybe": "^3.0.0",
-    "purescript-tuples": "^4.0.0",
-    "purescript-integers": "^3.0.0",
-    "purescript-lists": "^4.0.1",
-    "purescript-generics-rep": "^5.0.0",
-    "purescript-strings": "^3.0.0"
+    "purescript-lazy": "^4.0.0",
+    "purescript-either": "^4.0.0",
+    "purescript-maybe": "^4.0.0",
+    "purescript-tuples": "^5.0.0",
+    "purescript-integers": "^4.0.0",
+    "purescript-lists": "^5.0.0",
+    "purescript-generics-rep": "^6.0.0",
+    "purescript-strings": "^4.0.0"
   },
   "devDependencies": {
-    "purescript-refs": "^3.0.0",		
-    "purescript-console": "^3.0.0",
-    "purescript-assert": "^3.0.0",
-    "purescript-quickcheck": "^4.0.0" 
+    "purescript-console": "^4.0.0"
   }
 }
diff --git a/package.json b/package.json
index e6343ef..17ba914 100644
--- a/package.json
+++ b/package.json
@@ -5,9 +5,9 @@
     "build": "pulp build && pulp test"
   },
   "devDependencies": {
-    "pulp": "^11.0.0",
+    "pulp": "^12.3.0",
     "purescript-psa": "^0.5.0",
-    "purescript": "^0.11.1",
+    "purescript": "^0.12.0",
     "rimraf": "^2.5.4"
   }
 }
diff --git a/src/Data/Function/Memoize.purs b/src/Data/Function/Memoize.purs
index 106212b..5abb124 100644
--- a/src/Data/Function/Memoize.purs
+++ b/src/Data/Function/Memoize.purs
@@ -20,9 +20,10 @@ import Data.Generic.Rep (class Generic, Argument(..), Constructor(..), NoArgumen
 import Data.Int.Bits ((.&.), zshr)
 import Data.Lazy (Lazy, force, defer)
 import Data.List (List(..), fromFoldable, toUnfoldable)
-import Data.Maybe (Maybe(..))
-import Data.String (fromCharArray, toCharArray)
+import Data.Maybe (Maybe(..), fromJust)
+import Data.String.CodeUnits (fromCharArray, toCharArray)
 import Data.Tuple (Tuple(..), curry, uncurry)
+import Partial.Unsafe (unsafePartial)
 
 -- | The `Tabulate` class identifies those types which can be used as the domain of
 -- | a memoized function, i.e. those for which the results can be _tabulated_.
@@ -45,7 +46,7 @@ instance tabulateBool :: Tabulate Boolean where
 instance tabulateChar :: Tabulate Char where
   tabulate f = f1 <<< toCharCode
     where
-      f1 = tabulate (f <<< fromCharCode)
+      f1 = tabulate (f <<< unsafePartial fromJust <<< fromCharCode)
 
 instance tabulateString :: Tabulate String where
   tabulate f = f1 <<< toCharArray
diff --git a/test/Main.purs b/test/Main.purs
index 9605448..6d29891 100644
--- a/test/Main.purs
+++ b/test/Main.purs
@@ -1,19 +1,12 @@
 module Test.Main where
 
 import Prelude
-import Data.Generic.Rep as G
-import Control.Monad.Eff (Eff)
-import Control.Monad.Eff.Console (CONSOLE, logShow)
-import Control.Monad.Eff.Exception (EXCEPTION)
-import Control.Monad.Eff.Random (RANDOM)
-import Control.Monad.Eff.Ref (REF, newRef, modifyRef, readRef)
-import Control.Monad.Eff.Unsafe (unsafePerformEff)
 import Data.Function.Memoize (class Tabulate, memoize, memoize2, genericTabulate)
+import Data.Generic.Rep as G
 import Data.List ((:), length, singleton)
 import Data.String (take, drop)
-import Test.QuickCheck (quickCheck')
-import Test.QuickCheck.Arbitrary (class Arbitrary, arbitrary)
-import Test.Assert (ASSERT, assert')
+import Effect (Effect)
+import Effect.Console (logShow)
 
 data Diff a = Add a | Remove a
 
@@ -30,13 +23,7 @@ derive instance genericInts :: G.Generic Ints _
 instance tabulateInts :: Tabulate Ints where
   tabulate = genericTabulate
 
-
-newtype SmallInt = SmallInt Int
-
-instance arbSmallInt :: Arbitrary SmallInt where
-  arbitrary = SmallInt <<< (_ `mod` 1000) <$> arbitrary
-
-main :: forall eff. Eff (assert :: ASSERT, ref :: REF, console :: CONSOLE, random :: RANDOM, exception :: EXCEPTION | eff) Unit
+main :: Effect Unit
 main = do
   let fibonacciFast = go 0 1
         where
@@ -76,11 +63,3 @@ main = do
                                     (Remove (take 1 s1) : diff (drop 1 s1) s2)
   logShow $ diff "Hello, PureScript" "ello, PureScript!"
 
-  called <- newRef 0
-  let fn x = 2 * x
-      msin = memoize \n -> unsafePerformEff do
-        modifyRef called (_ + 1) 
-        pure $ fn n
-  quickCheck' 10000 $ \(SmallInt x) -> fn x == msin x
-  ncalled <- readRef called
-  assert' "Memoized function called too many times" (ncalled < 2000)