diff --git a/demo/Main.hs b/demo/Main.hs
--- a/demo/Main.hs
+++ b/demo/Main.hs
@@ -19,27 +19,31 @@
 -- so-often.
 main = do
   (s, trees, values) <- storage
-  mapM_ (doRun s trees) [0,100..1000::Int]
+  mapM_ (doRun s trees values) [0,100..1000::Int]
   store s (fromMap $ Map.fromList [(a,a+1)|a<-[100..1000]])
-  prTrees trees
+  prTrees trees values
   store s (fromMap $ Map.fromList [(a,a+1)|a<-[200..1000]])
-  prTrees trees
+  prTrees trees values
   store s (fromMap $ Map.fromList [(a,a+1)|a<-[0..400]++[600..1000]])
-  prTrees trees
+  prTrees trees values
 
   where
-  doRun s trees i = do
+  doRun s trees values i = do
     mapM_ (upd s) [i..i+100]
     putStr $ stupidCount (i+100) ++ " "
-    prTrees trees
+    prTrees trees values
 
   upd s i = do
     let m = Map.fromList [(a,a+1) | a <- [0..i]]
         t = fromMap m
     store s t
 
-  prTrees trees = 
-    readIORef trees >>= return . length . Map.keys >>= print
+  prTrees trees values = do
+    tnum <- readIORef trees >>= return . Map.size
+    tsum <- readIORef trees >>= return . sum . map (Map.size . snd) . Map.elems
+    vsum <- readIORef values >>= return . Map.size
+    putStrLn $ show (tsum+vsum) ++ " (" ++ show tnum ++ "," ++ show tsum
+               ++ "," ++ show vsum ++ ")"
 
 -- |The typical way of storing key/value maps in SQL is to use a relational
 -- table, like this:
diff --git a/stable-tree.cabal b/stable-tree.cabal
--- a/stable-tree.cabal
+++ b/stable-tree.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                stable-tree
-version:             0.0.1
+version:             0.0.2
 synopsis:            Trees whose branches are resistant to change
 -- description:         
 homepage:            https://github.com/tsuraan/stable-tree
@@ -39,7 +39,7 @@
                      , cereal
                      , containers
                      , hs-blake2
-                     , mtl
+                     , mtl >= 2.2.1
                      , text
   hs-source-dirs:      src
   default-language:    Haskell2010
@@ -51,7 +51,7 @@
   build-depends:       base >=4.6 && < 4.8
                      , bytestring-arbitrary
                      , containers
-                     , QuickCheck
+                     , QuickCheck >= 2.1
                      , stable-tree
                      , tasty
                      , tasty-quickcheck