diff --git a/AUTHORS b/AUTHORS
--- a/AUTHORS
+++ b/AUTHORS
@@ -1,6 +1,6 @@
 === Haskell unification-fd package AUTHORS/THANKS file ===
 
-The unification-fd package was written by wren ng thornton and is
+The unification-fd package was written by wren gayle romano and is
 released under the terms in the LICENSE file.
 
 
@@ -18,10 +18,12 @@
     suggsting the switch to having variables be of kind * rather
     than *->*
 
-Roman Cheplyaka -- for suggesting the switching of type parameter
+Roman Cheplyaka --- for suggesting the switching of type parameter
     order on UTerm so that it actually is the free monad. And
     for providing the freshenAll implementation.
 
+Graham Rogers --- for suggesting the addition of Functor, Foldable,
+    and Traversable instances for UnificationFailure.
 
 === Related Work ===
 
diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -10,7 +10,7 @@
 
 === unification-fd license ===
 
-Copyright (c) 2007, 2008, 2011, 2012, wren ng thornton.
+Copyright (c) 2007, 2008, 2011, 2012, 2013, 2014, wren gayle romano.
 ALL RIGHTS RESERVED.
 
 Redistribution and use in source and binary forms, with or without
diff --git a/README b/README
--- a/README
+++ b/README
@@ -17,10 +17,12 @@
     $> runhaskell Setup.hs build
     $> runhaskell Setup.hs test
     $> runhaskell Setup.hs haddock --hyperlink-source
-    $> runhaskell Setup.hs install
+    $> runhaskell Setup.hs copy
+    $> runhaskell Setup.hs register
 
-The test step is optional and currently does nothing. If you see
-some stray lines that look like this:
+The test step is optional and currently does nothing. The Haddock
+step is also optional. If you see some stray lines that look like
+this:
 
     mkUsageInfo: internal name? t{tv a7XM}
 
diff --git a/VERSION b/VERSION
--- a/VERSION
+++ b/VERSION
@@ -1,4 +1,6 @@
-0.8.0 (2012-00-00):
+0.8.1 (2014-05-27):
+    - Control.Unification.Types: added Functor, Foldable, and Traversable instances for UnificationFailure. (h/t Graham Rogers)
+0.8.0 (2012-07-11):
     - Control.Unification.Types: Changed the type of Unifiable.zipMatch
 0.7.0 (2012-03-19):
     - Renamed MutTerm to UTerm (and MutVar to UVar)
diff --git a/src/Control/Monad/State/UnificationExtras.hs b/src/Control/Monad/State/UnificationExtras.hs
--- a/src/Control/Monad/State/UnificationExtras.hs
+++ b/src/Control/Monad/State/UnificationExtras.hs
@@ -4,7 +4,7 @@
 --                                                  ~ 2011.07.05
 -- |
 -- Module      :  Control.Monad.State.UnificationExtras
--- Copyright   :  Copyright (c) 2008--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2008--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  perpetually unstable
diff --git a/src/Control/Unification.hs b/src/Control/Unification.hs
--- a/src/Control/Unification.hs
+++ b/src/Control/Unification.hs
@@ -4,7 +4,7 @@
 --                                                  ~ 2012.03.25
 -- |
 -- Module      :  Control.Unification
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  experimental
@@ -64,7 +64,7 @@
     , getFreeVarsAll
     , applyBindingsAll
     , freshenAll
-    -- subsumesAll -- to ensure that there's a single coherent substitution allowing the schema to subsume all the terms in some collection. 
+    -- subsumesAll -- to ensure that there's a single coherent substitution allowing the schema to subsume all the terms in some collection.
 
     -- * Helper functions
     -- | Client code should not need to use these functions, but
@@ -129,7 +129,7 @@
         mb <- lookupVar v0
         case mb of
             Nothing -> return t0
-            Just t  -> 
+            Just t  ->
                 case t  of
                 UTerm _  -> return t0
                 UVar  v  -> do
@@ -212,7 +212,7 @@
     where
     -- TODO: is that the most efficient direction/associativity?
     loopAll = foldrM (\t r -> IM.union r <$> loop t) IM.empty
-    
+
     loop t0 = do
         t0 <- lift $ semiprune t0
         case t0 of
diff --git a/src/Control/Unification/IntVar.hs b/src/Control/Unification/IntVar.hs
--- a/src/Control/Unification/IntVar.hs
+++ b/src/Control/Unification/IntVar.hs
@@ -7,7 +7,7 @@
 --                                                  ~ 2012.03.18
 -- |
 -- Module      :  Control.Unification.IntVar
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  experimental
diff --git a/src/Control/Unification/Ranked.hs b/src/Control/Unification/Ranked.hs
--- a/src/Control/Unification/Ranked.hs
+++ b/src/Control/Unification/Ranked.hs
@@ -4,7 +4,7 @@
 --                                                  ~ 2012.03.25
 -- |
 -- Module      :  Control.Unification.Ranked
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  highly experimental
diff --git a/src/Control/Unification/Ranked/IntVar.hs b/src/Control/Unification/Ranked/IntVar.hs
--- a/src/Control/Unification/Ranked/IntVar.hs
+++ b/src/Control/Unification/Ranked/IntVar.hs
@@ -7,7 +7,7 @@
 --                                                  ~ 2012.03.18
 -- |
 -- Module      :  Control.Unification.Ranked.IntVar
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  highly experimental
diff --git a/src/Control/Unification/Ranked/STVar.hs b/src/Control/Unification/Ranked/STVar.hs
--- a/src/Control/Unification/Ranked/STVar.hs
+++ b/src/Control/Unification/Ranked/STVar.hs
@@ -8,7 +8,7 @@
 --                                                  ~ 2012.03.18
 -- |
 -- Module      :  Control.Unification.Ranked.STVar
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  highly experimental
diff --git a/src/Control/Unification/STVar.hs b/src/Control/Unification/STVar.hs
--- a/src/Control/Unification/STVar.hs
+++ b/src/Control/Unification/STVar.hs
@@ -8,7 +8,7 @@
 --                                                  ~ 2012.03.18
 -- |
 -- Module      :  Control.Unification.STVar
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  experimental
diff --git a/src/Control/Unification/Types.hs b/src/Control/Unification/Types.hs
--- a/src/Control/Unification/Types.hs
+++ b/src/Control/Unification/Types.hs
@@ -5,10 +5,10 @@
 
 {-# OPTIONS_GHC -Wall -fwarn-tabs #-}
 ----------------------------------------------------------------
---                                                  ~ 2012.03.25
+--                                                  ~ 2014.05.27
 -- |
 -- Module      :  Control.Unification.Types
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  experimental
@@ -38,6 +38,7 @@
 
 import Data.Word               (Word8)
 import Data.Functor.Fixedpoint (Fix(..))
+import Data.Monoid             (Monoid(..), (<>))
 import Data.Foldable           (Foldable(..))
 import Data.Traversable        (Traversable(..))
 import Control.Applicative     (Applicative(..), (<$>), Alternative(..))
@@ -136,6 +137,8 @@
 -- could be given more accurate types if we used ad-hoc combinations
 -- of these constructors (i.e., because they can only throw one of
 -- the errors), the extra complexity is not considered worth it.
+--
+-- /Updated: 0.8.1/ added 'Functor', 'Foldable', and 'Traversable' instances.
 data UnificationFailure t v
     
     = OccursIn v (UTerm t v)
@@ -196,6 +199,24 @@
 instance Error (UnificationFailure t v) where
     noMsg  = UnknownError ""
     strMsg = UnknownError
+
+
+instance (Functor t) => Functor (UnificationFailure t) where
+    fmap f (OccursIn v t)       = OccursIn (f v) (fmap f t)
+    fmap f (TermMismatch tl tr) = TermMismatch (fmap f <$> tl) (fmap f <$> tr)
+    fmap _ (UnknownError msg)   = UnknownError msg
+
+instance (Foldable t) => Foldable (UnificationFailure t) where
+    foldMap f (OccursIn v t)       = f v <> foldMap f t
+    foldMap f (TermMismatch tl tr) = foldMap (foldMap f) tl
+                                  <> foldMap (foldMap f) tr
+    foldMap _ (UnknownError _)     = mempty
+
+instance (Traversable t) => Traversable (UnificationFailure t) where
+    traverse f (OccursIn v t)       = OccursIn <$> f v <*> traverse f t
+    traverse f (TermMismatch tl tr) = TermMismatch <$> traverse (traverse f) tl 
+                                                   <*> traverse (traverse f) tr
+    traverse _ (UnknownError msg)   = pure (UnknownError msg)
 
 ----------------------------------------------------------------
 
diff --git a/src/Data/Functor/Fixedpoint.hs b/src/Data/Functor/Fixedpoint.hs
--- a/src/Data/Functor/Fixedpoint.hs
+++ b/src/Data/Functor/Fixedpoint.hs
@@ -2,15 +2,26 @@
 {-# LANGUAGE UndecidableInstances #-}
 -- For 'build' and 'hmap'
 {-# LANGUAGE Rank2Types #-}
--- To parse rules. The language extension is for hackery in rules.
-{-# OPTIONS_GHC -O2 -fglasgow-exts #-}
 
+-- Unfortunately GHC < 6.10 needs -fglasgow-exts in order to actually
+-- parse RULES (see -ddump-rules); the -frewrite-rules flag only
+-- enables the application of rules, instead of doing what we want.
+-- Apparently this is fixed in 6.10. In newer GHC (e.g., 7.6.1) the
+-- -frewrite-rules flag is deprecated in favor of -fenable-rewrite-rules.
+-- It's unclear whether we can use CPP to switch between -fglasgow-exts
+-- -frewrite-rules and -fenable-rewrite-rules based on the GHC
+-- version...
+--
+-- http://hackage.haskell.org/trac/ghc/ticket/2213
+-- http://www.mail-archive.com/glasgow-haskell-users@haskell.org/msg14313.html
+{-# OPTIONS_GHC -O2 -fenable-rewrite-rules #-}
+
 {-# OPTIONS_GHC -Wall -fwarn-tabs #-}
 ----------------------------------------------------------------
---                                                    2012.07.10
+--                                                    2013.05.11
 -- |
 -- Module      :  Data.Functor.Fixedpoint
--- Copyright   :  Copyright (c) 2007--2012 wren ng thornton
+-- Copyright   :  Copyright (c) 2007--2014 wren gayle romano
 -- License     :  BSD
 -- Maintainer  :  wren@community.haskell.org
 -- Stability   :  provisional
diff --git a/unification-fd.cabal b/unification-fd.cabal
--- a/unification-fd.cabal
+++ b/unification-fd.cabal
@@ -1,5 +1,5 @@
 ----------------------------------------------------------------
--- wren ng thornton <wren@community.haskell.org>    ~ 2012.03.25
+-- wren gayle romano <wren@community.haskell.org>    ~ 2014.05.27
 ----------------------------------------------------------------
 
 -- By and large Cabal >=1.2 is fine; but >= 1.6 gives tested-with:
@@ -8,12 +8,12 @@
 Build-Type:     Simple
 
 Name:           unification-fd
-Version:        0.8.0
+Version:        0.8.1
 Stability:      experimental
 Homepage:       http://code.haskell.org/~wren/
-Author:         wren ng thornton
+Author:         wren gayle romano
 Maintainer:     wren@community.haskell.org
-Copyright:      Copyright (c) 2007--2012 wren ng thornton
+Copyright:      Copyright (c) 2007--2014 wren gayle romano
 License:        BSD3
 License-File:   LICENSE
 
@@ -21,6 +21,9 @@
 Synopsis:       Simple generic unification algorithms.
 Description:    Simple generic unification algorithms.
 
+-- BUG: does not work with GHC 7.8.0. Need to fix that
+Tested-With:
+    GHC == 6.12.1, GHC == 7.6.1
 Extra-source-files:
     AUTHORS, README, VERSION
 Source-Repository head