diff --git a/pkg/hs-urbit/lib/Noun/Cue/Fast.hs b/pkg/hs-urbit/lib/Noun/Cue/Fast.hs
index 319506f1d0..de32d50fec 100644
--- a/pkg/hs-urbit/lib/Noun/Cue/Fast.hs
+++ b/pkg/hs-urbit/lib/Noun/Cue/Fast.hs
@@ -106,8 +106,9 @@ type Bits = Vector Bool
 doGet :: Get a -> ByteString -> Either DecodeExn a
 doGet m bs =
   unsafePerformIO $ try $ BS.unsafeUseAsCStringLen bs \(ptr, len) -> do
+    -- traceM ("cue size: " <> show (length bs `div` 10))
     let endPtr = ptr `plusPtr` len
-    tbl <- H.new -- Sized 1000000
+    tbl <- H.newSized (length bs `div` 10)
     GetResult _ r <- runGet m endPtr tbl (S (castPtr ptr) 0 0)
     pure r
 
diff --git a/pkg/hs-urbit/lib/Noun/Fat.hs b/pkg/hs-urbit/lib/Noun/Fat.hs
index dd7c259335..d9183b88bc 100644
--- a/pkg/hs-urbit/lib/Noun/Fat.hs
+++ b/pkg/hs-urbit/lib/Noun/Fat.hs
@@ -6,7 +6,8 @@
 {-# OPTIONS_GHC -fwarn-unused-binds -fwarn-unused-imports #-}
 
 module Noun.Fat ( FatNoun(..)
-                , fatHash, fatCell, fatAtom
+                , fatSize, fatHash
+                , fatCell, fatAtom
                 , toFatNoun, fromFatNoun
                 ) where
 
@@ -26,6 +27,7 @@ import Noun                      (Noun(Atom, Cell))
 
 data FatNoun
     = FatCell {-# UNPACK #-} !Int
+              !Word
               !FatNoun
               !FatNoun
     | FatWord {-# UNPACK #-} !Word
@@ -50,8 +52,8 @@ instance Eq FatNoun where
                   w1==w2
               (FatAtom x1 a1,    FatAtom x2 a2   ) ->
                   x1==x2 && a1==a2
-              (FatCell x1 h1 t1, FatCell x2 h2 t2) ->
-                  x1==x2 && h1==h2 && t1==t2
+              (FatCell x1 s1 h1 t1, FatCell x2 s2 h2 t2) ->
+                  s1==s2 && x1==x2 && h1==h2 && t1==t2
               (_,                _               ) ->
                   False
   {-# INLINE (==) #-}
@@ -59,12 +61,17 @@ instance Eq FatNoun where
 
 --------------------------------------------------------------------------------
 
+fatSize :: FatNoun -> Word
+fatSize = \case
+  FatCell _ s _ _ -> s
+  _               -> 1
+
 {-# INLINE fatHash #-}
 fatHash :: FatNoun -> Int
 fatHash = \case
-  FatCell h _ _ -> h
-  FatAtom h _   -> h
-  FatWord w     -> hash w
+  FatCell h _ _ _ -> h
+  FatAtom h _     -> h
+  FatWord w       -> hash w
 
 {-# INLINE fatAtom #-}
 fatAtom :: Atom -> FatNoun
@@ -74,8 +81,9 @@ fatAtom = \case
 
 {-# INLINE fatCell #-}
 fatCell :: FatNoun -> FatNoun -> FatNoun
-fatCell h t = FatCell has h t
+fatCell h t = FatCell has siz h t
   where
+    siz = fatSize h + fatSize t
     has = fatHash h `combine` fatHash t
 
 {-# INLINE toFatNoun #-}
@@ -89,9 +97,9 @@ toFatNoun = go
 fromFatNoun :: FatNoun -> Noun
 fromFatNoun = go
   where go = \case
-          FatAtom _ a   -> Atom (MkAtom $ NatJ# a)
-          FatCell _ h t -> Cell (go h) (go t)
-          FatWord w     -> Atom (fromIntegral w)
+          FatAtom _ a     -> Atom (MkAtom $ NatJ# a)
+          FatCell _ _ h t -> Cell (go h) (go t)
+          FatWord w       -> Atom (fromIntegral w)
 
 
 -- Stolen from Hashable Library ------------------------------------------------
diff --git a/pkg/hs-urbit/lib/Noun/Jam/Fast.hs b/pkg/hs-urbit/lib/Noun/Jam/Fast.hs
index 1974491f94..f3dd6c71ef 100644
--- a/pkg/hs-urbit/lib/Noun/Jam/Fast.hs
+++ b/pkg/hs-urbit/lib/Noun/Jam/Fast.hs
@@ -269,9 +269,9 @@ writeNoun :: FatNoun -> Put ()
 writeNoun n =
   getRef >>= \case
     Just bk -> writeBackRef bk
-    Nothing -> case n of FatAtom _ n    -> writeAtom (MkAtom $ NatJ# n)
-                         FatWord (W# w) -> writeAtom (MkAtom $ NatS# w)
-                         FatCell _ h t  -> writeCell h t
+    Nothing -> case n of FatAtom _ n     -> writeAtom (MkAtom $ NatJ# n)
+                         FatWord (W# w)  -> writeAtom (MkAtom $ NatS# w)
+                         FatCell _ _ h t -> writeCell h t
 
 {-# INLINE writeMat #-}
 writeMat :: Atom -> Put ()
@@ -340,18 +340,24 @@ jamWordSz (W# w) = 1 + 2*(W# preW) + (W# atmW)
 compress :: FatNoun -> IO (Word, H.CuckooHashTable Word Word)
 compress top = do
     -- traceM "<compress>"
-    nodes :: H.BasicHashTable  FatNoun Word <- H.new -- Sized 1000000
-    backs :: H.CuckooHashTable Word    Word <- H.new -- Sized 1000000
+    let sz =  10 ^ (floor $ logBase 600 (fromIntegral $ fatSize top))
+
+    -- traceM ("inp(" <> show (fatSize top) <> ")")
+    -- traceM ("sz(" <> show sz <> ")")
+
+    nodes :: H.BasicHashTable  FatNoun Word <- H.newSized sz
+    backs :: H.CuckooHashTable Word    Word <- H.newSized sz
 
     let proc :: Word -> FatNoun -> IO Word
         proc pos = \case
             n@(FatAtom _ a) -> pure $ atomSz (MkAtom (NatJ# a))
             FatWord w       -> pure (jamWordSz w)
-            FatCell _ h t   -> do
+            FatCell _ _ h t -> do
                 !hSz <- go (pos+2) h
                 !tSz <- go (pos+2+hSz) t
                 pure (2+hSz+tSz)
 
+
         go :: Word -> FatNoun -> IO Word
         go p inp = do
             H.lookup nodes inp >>= \case
@@ -363,7 +369,7 @@ compress top = do
                         doRef = H.insert backs p bak $> rs
                         noRef = proc p inp
                     case inp of
-                        FatCell _ _ _                                -> doRef
+                        FatCell _ _ _ _                              -> doRef
                         FatWord w   | rs < atomSz (fromIntegral w)   -> doRef
                         FatAtom _ a | rs < atomSz (MkAtom (NatJ# a)) -> doRef
                         _                                            -> noRef
diff --git a/pkg/hs-urbit/lib/Noun/Lens.hs b/pkg/hs-urbit/lib/Noun/Lens.hs
index 8a4abe6bee..51edb786b9 100644
--- a/pkg/hs-urbit/lib/Noun/Lens.hs
+++ b/pkg/hs-urbit/lib/Noun/Lens.hs
@@ -38,21 +38,17 @@ dumpJam fp = writeFile fp . view (re _CueFatBytes)
 
 tryCuePill :: PillFile -> IO ()
 tryCuePill pill =
-    loadNoun (show pill) >>= \case Nothing              -> print "nil"
+    loadNoun (show pill) >>= \case Nothing            -> print "nil"
                                    Just (FatAtom _ _) -> print "atom"
-                                   Just (FatWord _)     -> print "word"
-                                   _                    -> print "cell"
+                                   Just (FatWord _)   -> print "word"
+                                   _                  -> print "cell"
 
 tryCueJamPill :: PillFile -> IO ()
 tryCueJamPill pill = do
-
   n <- loadNoun (show pill) >>= \case
-         Nothing -> do print "failure"
-                       pure (FatWord 0)
-         Just n@(FatAtom _ _) -> do print "atom"
-                                    pure n
-         Just n@(FatCell _ _ _) -> do print "cell"
-                                      pure n
+         Nothing                  -> print "failure" >> pure (FatWord 0)
+         Just n@(FatAtom _ _)     -> print "atom"    >> pure n
+         Just n@(FatCell _ _ _ _) -> print "cell"    >> pure n
 
   bs <- evaluate (force (jamFatBS n))