diff --git a/CHANGELOG.md b/CHANGELOG.md
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--- /dev/null
+++ b/CHANGELOG.md
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+              GNU GENERAL PUBLIC LICENSE
+                Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                     Preamble
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+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+              END OF TERMS AND CONDITIONS
+
+     How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/poly-rec.cabal b/poly-rec.cabal
new file mode 100644
--- /dev/null
+++ b/poly-rec.cabal
@@ -0,0 +1,30 @@
+-- Initial polykheXrec.cabal generated by cabal init.  For further
+-- documentation, see http://haskell.org/cabal/users-guide/
+
+name:                poly-rec
+version:             0.6.0.0
+synopsis:            Polykinded extensible records
+description:         Extensible records/row polymorphism for Haskell. Fields are polykinded,
+                     to statically check rich structures. This library was initially conceived
+                     as part of the AspectAG project.
+license:             GPL-3
+license-file:        LICENSE
+author:              Juan García-Garland
+maintainer:          jpgarcia@fing.edu.uy
+copyright:           2020, Juan García-Garland, Marcos Viera, Alberto Pardo
+category:            Data
+build-type:          Simple
+extra-source-files:  CHANGELOG.md
+cabal-version:       >=1.10
+
+library
+  exposed-modules: Data.GenRec,
+                   Data.GenRec.Label,
+                   Data.GenRec.RecInstances.Record
+                   
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       requirements >= 0.6.0.0 && < 0.7,
+                       base >=4.11 && <4.15
+  hs-source-dirs:      src
+  default-language:    Haskell2010
diff --git a/src/Data/GenRec.hs b/src/Data/GenRec.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/GenRec.hs
@@ -0,0 +1,416 @@
+{-|
+Module      : Data.GenRecord
+Description : polykinded extensible record library
+Copyright   : (c) Juan García Garland,
+                  Marcos Viera, 2019-2020
+License     : GPL
+Maintainer  : jpgarcia@fing.edu.uy
+Stability   : experimental
+Portability : POSIX
+
+Extensible records/row polymorphism are features not implemented in
+Haskell. Some other functional languages do it, like Purescript. GHC
+extensions allowing type level-programming allow us to encode them in
+Haskell.
+
+Let us define records as a (partial) mapping from names (fields, wich
+are static) to values.
+
+There are many implementations out there. This is yet another one,
+inspired in the HList library. It arose when programming the AspectAG
+library.  Before, we depended on HList. Then we choose to implement a
+record library from scratch for two reasons:
+
+ * HList is experimental, it does not maintain a stable interface.
+ * We prefer a solution that fits better in our use case.
+
+AspectAG is a library to encode type safe attribute grammars.
+Statically checked extensible records are used everywhere, knowing at
+compile time the structure of the grammar, and checking if it is
+well-formed.
+
+Some example structures in AspectAG library are:
+
+* Records: that's it, plane extensible records: Mappings from names to
+  values.
+
+* Attributions: mappings from attribute names to values. This is the
+  same idea that the one for records, but we wanted to have different
+  types for each structure, and for each label. This means that our
+  labels must be polyinded.
+
+* Children Records: That is a map from children to attibutions. It is
+  a record of records. 
+
+One common way to implement a record is by using a GADT. For instance indexed by
+the list of pairs (label, value). We want labels polykinded, and values are
+usually of kind Type, what makes sense since Type is the kind of
+inhabited types, and records store values.  However, in cases such as
+our children records, where we store attributions that are also
+represented by an indexed GADT, we would like to be able to reflect
+some of this structural information at the indexes of the record. This
+can be achieved if we are polymorphic in the kind of the types
+corresponding to the record fields.
+-}
+
+{-# OPTIONS_GHC -fno-warn-missing-methods #-}
+
+{-# LANGUAGE DataKinds,
+             TypeOperators,
+             PolyKinds,
+             GADTs,
+             TypeInType,
+             RankNTypes,
+             StandaloneDeriving,
+             FlexibleInstances,
+             FlexibleContexts,
+             ConstraintKinds,
+             MultiParamTypeClasses,
+             FunctionalDependencies,
+             UndecidableInstances,
+             ScopedTypeVariables,
+             TypeFamilies,
+             InstanceSigs,
+             AllowAmbiguousTypes,
+             TypeApplications,
+             PatternSynonyms
+#-}
+
+module Data.GenRec
+  (
+    Rec(ConsRec, EmptyRec),
+    TagField(TagField),
+    WrapField,
+    UnWrap,
+    untagField,
+    (.=.),
+    (#),
+    (.*.),
+    Cmp,
+    ShowRec,
+    ShowField,
+    OpLookup(OpLookup),
+    lookup,
+    OpExtend(OpExtend),
+    -- extend, TODO
+    OpUpdate(OpUpdate),
+    update,
+    emptyGenRec,
+    module Data.GenRec.Label
+  ) where
+
+import Data.Kind
+import Data.Proxy
+import Data.GenRec.Label
+import Data.Type.Require
+import Prelude hiding (lookup)
+
+import GHC.TypeLits
+
+
+type family a == b where
+  a == b = Equal a b
+
+
+-- | Record data structure for generic records (Internal). The `c`
+-- index indicates the kind of record (for each record instance, the
+-- user should define an index). The `r` index represents the mapping
+-- from labels to values.  Labels are of kind `k'`. Values are still
+-- polykinded (`k''`) since rich information can be statically
+-- represented here (for instance, when a record of records, or a
+-- record of Vectors is represented).  `k'` must implement the `Cmp`
+-- family, although it is not visible here for simplicity. Records are
+-- built putting fields ordered according to the `Cmp` result of its
+-- labels. __This constructors are not intended to be used to build__
+-- __records__, (`ConsRec` is the problematic one). Use the smart
+-- constructors `emptyRecord` and `.*.` instead. We export the
+-- constructors to pattern match on them. Although there are solutions
+-- to hide Constructors while supporting pattern matching, we kept
+-- it simple
+
+data Rec (c :: k) (r :: [(k', k'')]) :: Type where
+  EmptyRec :: Rec c '[] -- ^ empty record
+  ConsRec :: TagField c l v -> Rec c r -> Rec c ('( l, v) ': r) -- ^
+-- `ConsRec` takes a tagged field (`TagField`) and a record, to build
+-- a new record. Recall that fields should be ordered.
+
+-- | The empty Record. Note that it is polymorphic on the kind of record `c`.
+emptyGenRec = EmptyRec
+
+-- | 'TagField'
+data TagField (c :: k) (l :: k') (v :: k'') where
+  TagField :: Label c -> Label l -> WrapField c v -> TagField c l v -- ^
+-- `TagField` tags a value `v` with record and label information. `v`
+-- is polykinded, for instance we could be tagging some kind of
+-- record, because then we would build a matrix. In that case 'k''
+-- could be something as `[(kindforlabels, Type)]`. But `TagField`
+-- contains inhabited values, it tags values of a type of kind `Type`.
+-- In this example perhaps some value of
+-- type `Rec Something [(kindforlabels, Type)]`.
+-- That is the role of the `WrapField` family. Given `c`, the kind of
+-- record, and `v`, ir computes the wrapper.
+
+
+-- | TagField operator, note that 'c' will be ambiguous if not annotated.
+infix 4 .=.
+(l :: Label l) .=. (v :: v) = TagField Label l v
+
+
+-- | Given a type of record and its index, it computes the type of
+-- record inhabitants
+type family  WrapField (c :: k')  (v :: k) :: Type
+
+
+-- | The inverse of `WrapField`
+type family UnWrap (t :: Type) :: [(k,k')]
+type instance UnWrap (Rec c (r :: [(k, k')])) = (r :: [(k, k')])
+
+-- | This is the destructor of `TagField`. Note the use of `WrapField` here.
+untagField :: TagField c l v -> WrapField c v
+untagField (TagField lc lv v) = v
+
+-- | comparisson of Labels, this family is polykinded, each record-like
+-- structure must implement this family for its labels
+type family Cmp (a :: k) (b :: k) :: Ordering
+
+-- | Instance for Symbols
+type instance Cmp (a :: Symbol) (b :: Symbol) = CmpSymbol a b
+
+
+-- | Function to show the name of records (Record, Mapping, etc):
+type family ShowRec c :: Symbol
+
+-- | Function to show the field of the record ("field named", "children", "tag:", etc)
+type family ShowField c :: Symbol
+
+
+-- * Operations
+
+-- ** Lookup
+
+-- | Datatype for lookup (wrapper)
+data OpLookup (c :: Type)
+              (l  :: k)
+              (r  :: [(k, k')]) :: Type where
+  OpLookup :: Label l -> Rec c r -> OpLookup c l r
+
+-- | Datatype for lookup (internal)
+data OpLookup' (b  :: Ordering)
+               (c  :: Type)
+               (l  :: k)
+               (r  :: [(k, k')]) :: Type where
+  OpLookup' :: Proxy b -> Label l -> Rec c r -> OpLookup' b c l r
+
+-- | wrapper instance
+instance
+  Require (OpLookup' (Cmp l l') c l ('( l', v) ': r)) ctx
+  =>
+  Require (OpLookup c l ('( l', v) ': r)) ctx where
+  type ReqR (OpLookup c l ('( l', v) ': r)) =
+    ReqR (OpLookup' (Cmp l l') c l ('( l', v) ': r))
+  req ctx (OpLookup l r) =
+    req ctx (OpLookup' (Proxy @(Cmp l l')) l r)
+
+-- | error instance (looking up an empty record)
+instance
+  Require (OpError (Text "field not Found on " :<>: Text (ShowRec c)
+                     :$$: Text "looking up the " :<>: Text (ShowField c)
+                           :<>: Text " " :<>: ShowTE l
+                          )) ctx
+  =>
+  Require (OpLookup c l ( '[] :: [(k,k')])) ctx where
+  type ReqR (OpLookup c l ('[] :: [(k,k')])  ) = ()
+  req = undefined
+
+-- | label found!
+instance
+  Require (OpLookup' 'EQ c l ( '(l, v) ': r)) ctx where
+  type ReqR (OpLookup' 'EQ c l ( '(l, v) ': r)) =
+    WrapField c v
+  req Proxy (OpLookup' Proxy Label (ConsRec f _)) =
+    untagField f
+
+-- | label not {yet} found
+instance (Require (OpLookup c l r) ctx)
+  =>
+  Require (OpLookup' 'GT c l ( '(l', v) ': r)) ctx where
+  type ReqR (OpLookup' 'GT c l ( '(l', v) ': r)) =
+    ReqR (OpLookup c l r)
+  req ctx (OpLookup' Proxy l (ConsRec _ r)) =
+    req ctx (OpLookup l r)
+
+-- | ERROR, we are beyond the supposed position for the label |l|,
+-- so we can assert there is no field labelled |l|
+-- (ot the record is ill-formed)
+instance Require (OpError (Text "field not Found on " :<>: Text (ShowRec c)
+                     :$$: Text "looking up the " :<>: Text (ShowField c)
+                           :<>: Text " " :<>: ShowTE l
+                          )) ctx
+  =>
+  Require (OpLookup' 'LT c l ( '(l', v) ': r)) ctx where
+  type ReqR (OpLookup' 'LT  c l ( '(l', v) ': r)) = ()
+  req ctx (OpLookup' Proxy l (ConsRec _ r)) = ()
+
+-- | Pretty lookup
+(#) :: RequireR (OpLookup c l r) '[] v =>
+  Rec c r -> Label l -> v
+r # l = req (Proxy @ '[]) (OpLookup l r)
+
+
+-- ** update
+
+-- | update operator (wrapper)
+data OpUpdate (c  :: Type)
+              (l  :: k)
+              (v  :: k')
+              (r  :: [(k, k')]) :: Type where
+  OpUpdate :: Label l -> WrapField c v -> Rec c r
+           -> OpUpdate c l v r
+
+-- | update operator (internal)
+data OpUpdate' (b  :: Ordering)
+               (c  :: Type)
+               (l  :: k)
+               (v  :: k')
+               (r  :: [(k, k')]) :: Type where
+  OpUpdate' :: Proxy b -> Label l -> WrapField c v ->  Rec c r
+           -> OpUpdate' b c l v r
+
+-- | wrapper instance
+instance (Require (OpUpdate' (Cmp l l') c l v ( '(l', v') ': r) ) ctx )
+  =>
+  Require (OpUpdate c l v ( '(l', v') ': r) ) ctx where
+  type ReqR (OpUpdate c l v ( '(l', v') ': r) ) =
+    ReqR (OpUpdate' (Cmp l l') c l v ( '(l', v') ': r) )
+  req ctx (OpUpdate l f r) =
+    (req @(OpUpdate' (Cmp l l') _ _ v _ ))
+      ctx (OpUpdate' (Proxy @(Cmp l l')) l f r)
+
+-- | error instance
+instance (Require (OpError (Text "field not Found on " :<>: Text (ShowRec c)
+                    :$$: Text "updating the " :<>: Text (ShowField c)
+                     :<>: ShowTE l)) ctx)
+  =>
+  Require (OpUpdate c l v '[]) ctx where
+  type ReqR (OpUpdate c l v ('[] )  ) = Rec c '[]
+  req = undefined
+
+-- | label found
+instance 
+  Require (OpUpdate' 'EQ c l v ( '(l, v') ': r)) ctx where
+  type ReqR (OpUpdate' 'EQ c l v ( '(l, v') ': r)) =
+    Rec c ( '(l, v) ': r)
+  req ctx (OpUpdate' proxy label field (ConsRec tgf r)) =
+    ConsRec (TagField Label label field) r
+
+instance
+  ( Require (OpUpdate c l v r) ctx
+  , ( '(l', v') : r0)  ~ a -- only to unify kinds
+  , ReqR (OpUpdate c l v r) ~ Rec c r0
+  )
+   =>
+  Require (OpUpdate' 'GT c l v ( '(l',v') ': r)) ctx where
+  type ReqR (OpUpdate' 'GT c l v ( '(l',v') ': r)) =
+    Rec c ( '(l',v') ': (UnWrap (ReqR (OpUpdate c l v r))))
+  req ctx (OpUpdate' _ l f (ConsRec field (r :: Rec c r))) =
+    ConsRec field $ (req @(OpUpdate _ _ v r)) ctx (OpUpdate l f r)
+
+-- | ERROR, we are beyond the supposed position for the label |l|,
+-- so we can assert there is no field labelled with |l| to update
+-- (or the record is ill-formed)
+instance (Require (OpError (Text "field not Found on " :<>: Text (ShowRec c)
+                    :$$: Text "updating the " :<>: Text (ShowField c)
+                     :<>: ShowTE l)) ctx)
+  =>
+  Require (OpUpdate' 'LT c l v ( '(l',v') ': r)) ctx where
+  type ReqR (OpUpdate' 'LT c l v ( '(l',v') ': r)) =
+    ()
+  req = undefined
+
+-- | The update function. Given a `Label` and value, and a `Record`
+-- containing this label, it updates the value. It could change its
+-- type. It raises a custom type error if there is no field
+-- labelled with l.
+update (l :: Label l) (v :: v) (r :: Rec c r) =
+  req Proxy (OpUpdate @l @c @v @r l v r)
+
+-- | The lookup function. Given a `Label` and a `Record`, it returns
+-- the field at that position. It raises a custom type
+-- error if there is no field labelled with l.
+lookup (l :: Label l) (r :: Rec c r) =
+  req Proxy (OpLookup @c @l @r l r)
+
+-- ** Extension
+
+-- | extension operator (wrapper)
+data OpExtend (c :: Type)
+              (l  :: k)
+              (v  :: k')
+              (r  :: [(k, k')]) :: Type where
+  OpExtend :: Label l -> WrapField c v -> Rec c r
+           -> OpExtend c l v r
+
+-- | Extension operator (inner)
+data OpExtend' (b   :: Ordering)
+               (c   :: Type)
+               (l   :: k)
+               (v   :: k')
+               (r   :: [(k, k')]) :: Type where
+  OpExtend' :: Proxy b -> Label l -> WrapField c v -> Rec c r
+           -> OpExtend' b c l v r
+
+-- | extending an empty record
+instance
+  Require (OpExtend c l v '[]) ctx where
+  type ReqR (OpExtend c l v '[]) =
+    Rec c '[ '(l , v)]
+  req ctx (OpExtend l v EmptyRec) =
+    ConsRec (TagField (Label @c) l v) EmptyRec
+
+-- | wrapper instance
+
+instance
+  Require (OpExtend' (Cmp l l') c l v ('(l', v') : r)) ctx
+  =>
+  Require (OpExtend c l v ( '(l', v') ': r)) ctx where
+  type ReqR (OpExtend c l v ( '(l', v') ': r)) =
+    ReqR (OpExtend' (Cmp l l') c l v ( '(l', v') ': r))
+  req ctx (OpExtend l v (r :: Rec c ( '(l', v') ': r)) ) =
+    req ctx (OpExtend' @(Cmp l l') @l @c @v Proxy l v r)
+
+-- | keep looking
+instance
+  (Require (OpExtend c l v r) ctx
+  , ( '(l', v') ': r0 ) ~ a
+  , ReqR (OpExtend c l v r) ~ Rec c r0
+  )
+  =>
+  Require (OpExtend' 'GT c l v ( '(l', v') ': r)) ctx where
+  type ReqR (OpExtend' 'GT c l v ( '(l', v') ': r)) =
+    Rec c ( '(l', v') ': UnWrap (ReqR (OpExtend c l v r)))
+  req ctx (OpExtend' Proxy l v (ConsRec lv r)) =
+    ConsRec lv $ req ctx (OpExtend @_ @_ @v l v r)
+
+instance
+  Require (OpExtend' 'LT c l v ( '(l', v') ': r)) ctx where
+  type ReqR (OpExtend' 'LT c l v ( '(l', v') ': r)) =
+    Rec c ( '(l, v) ': ( '(l', v') ': r))
+  req ctx (OpExtend' Proxy l v r) =
+    ConsRec (TagField Label l v) r
+
+instance
+  (Require (OpError (Text "cannot extend " :<>: Text (ShowRec c)
+                     -- :<>: Text " because the label (" :<>: ShowT l
+                     -- :<>: Text ") already exists"
+                    :$$: Text "colision in " :<>: Text (ShowField c)
+                     :<>: Text " ":<>: ShowTE l)) ctx)
+  =>
+  Require (OpExtend' 'EQ c l v ( '(l, v') ': r)) ctx where
+  type ReqR (OpExtend' 'EQ c l v ( '(l, v') ': r)) = ()
+  req ctx = undefined
+
+
+-- | '.*.' the pretty cons, hiding require
+infixr 2 .*.
+(TagField c l v :: TagField c l v) .*. (r :: Rec c r) =
+  req emptyCtx (OpExtend @l @c @v @r l v r)
diff --git a/src/Data/GenRec/Label.hs b/src/Data/GenRec/Label.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/GenRec/Label.hs
@@ -0,0 +1,29 @@
+{-|
+Module      : Language.Grammars.AspectAG.Label
+Description : Labels (polykinded, phantom)
+Copyright   : (c) Juan García Garland, Marcos Viera 2020
+License     : GPL-3
+Maintainer  : jpgarcia@fing.edu.uy
+Stability   : experimental
+Portability : POSIX
+-}
+
+{-# LANGUAGE PolyKinds #-}
+{-# LANGUAGE DataKinds #-}
+
+module Data.GenRec.Label where
+import Data.Proxy
+
+data Label l = Label
+
+sndLabel :: Label '(a,b) -> Label b
+sndLabel _ = undefined
+
+fstLabel :: Label '(a,b) -> Label a
+fstLabel _ = undefined
+
+labelFromType :: a -> Label a
+labelFromType _ = Label
+
+proxyToLabel :: Proxy a -> Label a
+proxyToLabel _ = Label
diff --git a/src/Data/GenRec/RecInstances/Record.hs b/src/Data/GenRec/RecInstances/Record.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/GenRec/RecInstances/Record.hs
@@ -0,0 +1,116 @@
+{-# LANGUAGE DataKinds,
+             TypeOperators,
+             PolyKinds,
+             GADTs,
+             TypeInType,
+             RankNTypes,
+             StandaloneDeriving,
+             FlexibleInstances,
+             FlexibleContexts,
+             ConstraintKinds,
+             MultiParamTypeClasses,
+             FunctionalDependencies,
+             UndecidableInstances,
+             ScopedTypeVariables,
+             TypeFamilies,
+             InstanceSigs,
+             AllowAmbiguousTypes,
+             TypeApplications,
+             PatternSynonyms
+#-}
+
+module Data.GenRec.RecInstances.Record
+  (Record, Reco,
+   untag, getLabel,
+   (.==.), (.**.), (##),
+   emptyRecord
+  )
+  where
+
+import GHC.TypeLits
+import Data.Kind
+import Data.Proxy
+import Data.GenRec
+import Data.GenRec.Label
+
+
+-- | * Records
+
+-- | datatype definition
+type Record        = (Rec Reco :: [(Symbol, Type)] -> Type)
+
+-- | index type
+data Reco
+
+-- | field type
+type instance  WrapField Reco     (v :: Type) = v
+
+-- | Type level show utilities
+type instance ShowRec Reco         = "Record"
+type instance ShowField Reco       = "field named "
+
+
+type Tagged (l :: Symbol) (v :: Type) = TagField Reco l v
+pattern Tagged :: v -> Tagged l v
+pattern Tagged v = TagField Label Label v
+
+
+-- ** Constructors
+
+-- | Pretty Constructor
+infix 4 .==.
+(.==.) :: Label l -> v -> Tagged l v
+l .==. v = Tagged v
+
+-- | For the empty Record
+emptyRecord :: Record ('[] :: [(Symbol, Type)])
+emptyRecord = EmptyRec
+
+untag :: Tagged l v -> v
+untag (TagField _ _ v) = v
+
+-- * Destructors
+-- | Get a label
+getLabel :: Tagged l v -> Label l
+getLabel _ = Label
+
+-- | Lookup
+infixl 5 ##
+r ## (l :: Label l) = (#) @Reco @l r l
+
+-- | extension
+infixr 2 .**.
+(lv :: Tagged l v) .**. r = (.*.)  lv r
+-- The Tagged annotation is enough to unify everything
+
+instance ( Show v
+         , KnownSymbol l )
+  =>
+  Show (Tagged l v) where
+  show (Tagged v :: TagField Reco l v) =
+    symbolVal (proxyFrom (Label @ l)) ++ " : "++ show v
+     where proxyFrom :: Label l -> Proxy l
+           proxyFrom _ = Proxy
+
+instance Show (Record '[]) where
+  show _ = "{}"
+
+instance ( Show v
+         , KnownSymbol l)
+  =>
+  Show (Record '[ '(l, v)]) where
+  show (ConsRec lv EmptyRec) =
+    '{' : show lv ++ "}"
+
+instance ( Show v
+         , KnownSymbol l
+         , Show (Record ( '(l', v') ': r )))
+  =>
+  Show (Record ( '(l, v) ': '(l', v') ': r )) where
+  show (ConsRec lv r) =
+    let ('{':shr) = show r
+    in '{' : show lv ++ ", " ++ shr
+
+v1 = (Label @"boolean" .==. True) .**. emptyRecord
+v2 = (Label @"integer" .==. 3) .**. v1
+v3 = (Label @"text" .==. "wa") .**. v2