diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2016-2017, Dylan Simon
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Dylan Simon nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/Text/XML/HXT/Arrow/Pickle/Xml/Invertible.hs b/Text/XML/HXT/Arrow/Pickle/Xml/Invertible.hs
new file mode 100644
--- /dev/null
+++ b/Text/XML/HXT/Arrow/Pickle/Xml/Invertible.hs
@@ -0,0 +1,92 @@
+-- |Allow combining 'PU's using "Control.Invertible.Monoidal".
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+module Text.XML.HXT.Arrow.Pickle.Xml.Invertible
+  ( module Text.XML.HXT.Arrow.Pickle.Xml
+  , module Control.Invertible.Monoidal
+  , xpWhitespace
+  , xpTrim
+  , xpAnyCont
+  , xpAnyAttrs
+  , xpAny
+  , xpAnyElem
+  ) where
+
+import           Control.Invertible.Monoidal
+import           Control.Monad.State.Class (modify, state)
+import           Data.Char.Properties.XMLCharProps (isXmlSpaceChar)
+import qualified Data.Invertible as Inv
+import           Data.List (partition)
+import           Data.Void (absurd)
+import           Text.XML.HXT.Arrow.Pickle.Schema (Schema(Any), scEmpty, scSeq, scAlt, scNull)
+import           Text.XML.HXT.Arrow.Pickle.Xml
+import qualified Text.XML.HXT.Core as HXT
+import qualified Text.XML.HXT.DOM.XmlNode as XN
+
+instance Inv.Functor PU where
+  fmap (f Inv.:<->: g) p = PU -- xpWrap
+    { appPickle = appPickle p . g
+    , appUnPickle = fmap f $ appUnPickle p
+    , theSchema = theSchema p
+    }
+
+instance Monoidal PU where
+  unit = xpUnit
+  p >*< q = PU -- xpPair
+    { appPickle = \(a, b) -> appPickle p a . appPickle q b
+    , appUnPickle = do
+        a <- appUnPickle p 
+        b <- appUnPickle q
+        return (a, b)
+    , theSchema = theSchema p `scSeq` theSchema q
+    }
+
+instance MonoidalAlt PU where
+  zero = PU
+    { appPickle = \a _ -> absurd a
+    , appUnPickle = throwMsg "PU.zero"
+    , theSchema = scNull
+    }
+  p >|< q = PU
+    { appPickle = either (appPickle p) (appPickle q)
+    , appUnPickle = mchoice (Left <$> appUnPickle p) return (Right <$> appUnPickle q)
+    , theSchema = theSchema p `scAlt` theSchema q
+    }
+
+-- |Ignore any whitespace and produce nothing
+xpWhitespace :: PU ()
+xpWhitespace = PU
+  { appPickle = const id
+  , appUnPickle = modify $ \s -> s{ contents = dropWhile (any (all isXmlSpaceChar) . XN.getText) $ contents s }
+  , theSchema = scEmpty
+  }
+
+-- |Ignore leading whitespace
+xpTrim :: PU a -> PU a
+xpTrim = (xpWhitespace *<)
+
+-- |Like 'xpTrees' but more efficient
+xpAnyCont :: PU HXT.XmlTrees
+xpAnyCont = PU
+  { appPickle = \c s -> s{ contents = c ++ contents s }
+  , appUnPickle = state $ \s -> (contents s, s{ contents = [] })
+  , theSchema = Any -- XXX
+  }
+
+-- |All attributes
+xpAnyAttrs :: PU HXT.XmlTrees
+xpAnyAttrs = PU
+  { appPickle = \a s -> s{ attributes = a ++ attributes s }
+  , appUnPickle = state $ \s -> (attributes s, s{ attributes = [] })
+  , theSchema = Any -- XXX
+  }
+
+-- |Any content and attributes: combine 'xpAnyCont' and 'xpAnyAttrs'
+xpAny :: PU HXT.XmlTrees
+xpAny = (uncurry (++) Inv.:<->: partition XN.isAttr) >$< (xpAnyAttrs >*< xpAnyCont)
+
+-- |Any single element
+xpAnyElem :: PU HXT.XmlTree
+xpAnyElem = xpWrapEither 
+  ( \e -> if XN.isElem e then Right e else Left "xpAnyElem: any element expected"
+  , id
+  ) xpTree
diff --git a/invertible-hxt.cabal b/invertible-hxt.cabal
new file mode 100644
--- /dev/null
+++ b/invertible-hxt.cabal
@@ -0,0 +1,29 @@
+name:                invertible-hxt
+version:             0.1
+synopsis:            invertible transformer instances for HXT Picklers
+description:         Provides alternative syntax for HXT's Picklers (XML parser/generators) based on generic invertible Monoidal
+license:             BSD3
+license-file:        LICENSE
+author:              Dylan Simon
+maintainer:          dylan@dylex.net
+copyright:           2017
+category:            Composition, XML
+build-type:          Simple
+cabal-version:       >=1.10
+tested-with:         GHC == 7.10.3, GHC == 8.0.1
+
+source-repository head
+  type: git
+  location: https://github.com/dylex/invertible
+
+library
+  exposed-modules:
+    Text.XML.HXT.Arrow.Pickle.Xml.Invertible
+  build-depends:
+    base >= 4.8 && <5,
+    mtl,
+    hxt,
+    hxt-charproperties,
+    invertible
+  default-language:    Haskell2010
+  ghc-options: -Wall