diff --git a/src/Data/RandomWalkSimilarity.hs b/src/Data/RandomWalkSimilarity.hs
index deded9cbe..c944b3304 100644
--- a/src/Data/RandomWalkSimilarity.hs
+++ b/src/Data/RandomWalkSimilarity.hs
@@ -74,18 +74,18 @@ rws compare getLabel as bs
     (featurizedAs, featurizedBs, _, _, countersAndDiffs, allDiffs) =
       foldl' (\(as, bs, counterA, counterB, diffs, allDiffs) diff -> case runFree diff of
         Pure (Right (Delete term)) ->
-          (as <> pure (featurize counterA term), bs, succ counterA, counterB, diffs, allDiffs <> pure Nil)
+          (as <> pure (featurize counterA term), bs, succ counterA, counterB, diffs, allDiffs <> pure None)
         Pure (Right (Insert term)) ->
           (as, bs <> pure (featurize counterB term), counterA, succ counterB, diffs, allDiffs <> pure (Term (featurize counterB term)))
         syntax -> let diff' = free syntax >>= either identity pure in
           (as, bs, succ counterA, succ counterB, diffs <> pure (These counterA counterB, diff'), allDiffs <> pure (Index counterA))
       ) ([], [], 0, 0, [], []) sesDiffs
 
-    findNearestNeighbourToDiff :: TermOrIndexOrNil (UnmappedTerm f fields)
+    findNearestNeighbourToDiff :: TermOrIndexOrNone (UnmappedTerm f fields)
                                -> State (Int, UnmappedTerms f fields, UnmappedTerms f fields)
                                         (Maybe (These Int Int, Diff f (Record fields)))
     findNearestNeighbourToDiff termThing = case termThing of
-      Nil -> pure Nothing
+      None -> pure Nothing
       Term term -> Just <$> findNearestNeighbourTo term
       Index i -> do
         (_, unA, unB) <- get
@@ -224,7 +224,7 @@ data UnmappedTerm f fields = UnmappedTerm {
 }
 
 -- | Either a `term`, an index of a matched term, or nil.
-data TermOrIndexOrNil term = Term term | Index Int | Nil
+data TermOrIndexOrNone term = Term term | Index Int | None
 
 -- | An IntMap of unmapped terms keyed by their position in a list of terms.
 type UnmappedTerms f fields = IntMap (UnmappedTerm f fields)
@@ -244,8 +244,8 @@ defaultFeatureVectorDecorator getLabel = featureVectorDecorator getLabel default
 -- | Annotates a term with a feature vector at each node, parameterized by stem length, base width, and feature vector dimensions.
 featureVectorDecorator :: (Hashable label, Traversable f) => Label f fields label -> Int -> Int -> Int -> Term f (Record fields) -> Term f (Record (Vector.Vector Double ': fields))
 featureVectorDecorator getLabel p q d
-  = cata (\ (RCons gram rest :< functor) ->
-      cofree ((foldr (Vector.zipWith (+) . getField . extract) (unitVector d (hash gram)) functor .: rest) :< functor))
+  = cata (\ ((gram :. rest) :< functor) ->
+      cofree ((foldr (Vector.zipWith (+) . getField . extract) (unitVector d (hash gram)) functor :. rest) :< functor))
   . pqGramDecorator getLabel p q
 
 -- | Annotates a term with the corresponding p,q-gram at each node.
@@ -259,7 +259,7 @@ pqGramDecorator
 pqGramDecorator getLabel p q = cata algebra
   where
     algebra term = let label = getLabel term in
-      cofree ((gram label .: headF term) :< assignParentAndSiblingLabels (tailF term) label)
+      cofree ((gram label :. headF term) :< assignParentAndSiblingLabels (tailF term) label)
     gram label = Gram (padToSize p []) (padToSize q (pure (Just label)))
     assignParentAndSiblingLabels functor label = (`evalState` (replicate (q `div` 2) Nothing <> siblingLabels functor)) (for functor (assignLabels label))
 
@@ -267,10 +267,10 @@ pqGramDecorator getLabel p q = cata algebra
                  -> Term f (Record (Gram label ': fields))
                  -> State [Maybe label] (Term f (Record (Gram label ': fields)))
     assignLabels label a = case runCofree a of
-      RCons gram rest :< functor -> do
+      (gram :. rest) :< functor -> do
         labels <- get
         put (drop 1 labels)
-        pure $! cofree ((gram { stem = padToSize p (Just label : stem gram), base = padToSize q labels } .: rest) :< functor)
+        pure $! cofree ((gram { stem = padToSize p (Just label : stem gram), base = padToSize q labels } :. rest) :< functor)
     siblingLabels :: Traversable f => f (Term f (Record (Gram label ': fields))) -> [Maybe label]
     siblingLabels = foldMap (base . rhead . extract)
     padToSize n list = take n (list <> repeat empty)
diff --git a/src/Data/Record.hs b/src/Data/Record.hs
index 4c5f68bd1..bb645fb37 100644
--- a/src/Data/Record.hs
+++ b/src/Data/Record.hs
@@ -17,22 +17,18 @@ type DefaultFields fields = (HasField fields Category, HasField fields Range, Ha
 -- |
 -- | This is heavily inspired by Aaron Levin’s [Extensible Effects in the van Laarhoven Free Monad](http://aaronlevin.ca/post/136494428283/extensible-effects-in-the-van-laarhoven-free-monad).
 data Record :: [*] -> * where
-  RNil :: Record '[]
-  RCons :: h -> Record t -> Record (h ': t)
+  Nil :: Record '[]
+  (:.) :: h -> Record t -> Record (h ': t)
 
-infixr 0 .:
-
--- | Infix synonym for `RCons`: `a .: b .: RNil == RCons a (RCons b RNil)`.
-(.:) :: h -> Record t -> Record (h ': t)
-(.:) = RCons
+infixr 0 :.
 
 -- | Get the first element of a non-empty record.
 rhead :: Record (head ': tail) -> head
-rhead (RCons head _) = head
+rhead (head :. _) = head
 
 -- | Get the first element of a non-empty record.
 rtail :: Record (head ': tail) -> Record tail
-rtail (RCons _ tail) = tail
+rtail (_ :. tail) = tail
 
 
 -- Classes
@@ -48,19 +44,19 @@ class HasField (fields :: [*]) (field :: *) where
 -- OVERLAPPABLE is required for the HasField instances so that we can handle the two cases: either the head of the non-empty h-list is the requested field, or it isn’t. The third possible case (the h-list is empty) is rejected at compile-time.
 
 instance {-# OVERLAPPABLE #-} HasField fields field => HasField (notIt ': fields) field where
-  getField (RCons _ t) = getField t
-  setField (RCons h t) f = RCons h (setField t f)
+  getField (_ :. t) = getField t
+  setField (h :. t) f = h :. setField t f
 
 instance {-# OVERLAPPABLE #-} HasField (field ': fields) field where
-  getField (RCons h _) = h
-  setField (RCons _ t) f = RCons f t
+  getField (h :. _) = h
+  setField (_ :. t) f = f :. t
 
 
 instance (Show h, Show (Record t)) => Show (Record (h ': t)) where
-  showsPrec n (RCons h t) = showParen (n > 0) $ showsPrec 1 h . (" .: " <>) . shows t
+  showsPrec n (h :. t) = showParen (n > 0) $ showsPrec 1 h . (" :. " <>) . shows t
 
 instance Show (Record '[]) where
-  showsPrec n RNil = showParen (n > 0) ("RNil" <>)
+  showsPrec n Nil = showParen (n > 0) ("Nil" <>)
 
 instance (ToJSON h, ToJSONList (Record t)) => ToJSON (Record (h ': t)) where
   toJSON r = toJSONList (toJSONValues r)
@@ -72,21 +68,21 @@ class ToJSONList t where
   toJSONValues :: t -> [Value]
 
 instance (ToJSON h, ToJSONList (Record t)) => ToJSONList (Record (h ': t)) where
-  toJSONValues (RCons h t) = toJSON h : toJSONValues t
+  toJSONValues (h :. t) = toJSON h : toJSONValues t
 
 instance ToJSONList (Record '[]) where
   toJSONValues _ = []
 
 
 instance (Eq h, Eq (Record t)) => Eq (Record (h ': t)) where
-  RCons h1 t1 == RCons h2 t2 = h1 == h2 && t1 == t2
+  (h1 :. t1) == (h2 :. t2) = h1 == h2 && t1 == t2
 
 instance Eq (Record '[]) where
   _ == _ = True
 
 
 instance (Ord h, Ord (Record t)) => Ord (Record (h ': t)) where
-  RCons h1 t1 `compare` RCons h2 t2 = let h = h1 `compare` h2 in
+  (h1 :. t1) `compare` (h2 :. t2) = let h = h1 `compare` h2 in
     if h == EQ then t1 `compare` t2 else h
 
 instance Ord (Record '[]) where
@@ -94,7 +90,7 @@ instance Ord (Record '[]) where
 
 
 instance (Listable head, Listable (Record tail)) => Listable (Record (head ': tail)) where
-  tiers = cons2 RCons
+  tiers = cons2 (:.)
 
 instance Listable (Record '[]) where
-  tiers = cons0 RNil
+  tiers = cons0 Nil
diff --git a/src/FDoc/RecursionSchemes.hs b/src/FDoc/RecursionSchemes.hs
index b9c149513..772c6677c 100644
--- a/src/FDoc/RecursionSchemes.hs
+++ b/src/FDoc/RecursionSchemes.hs
@@ -28,7 +28,7 @@ The example below adds a new field to the `Record` fields.
 indexedTermAna :: [leaf] -> Term (Syntax leaf) (Record '[NewField, Range, Category])
 indexedTermAna childrenLeaves = ana coalgebra (indexedTerm childrenLeaves)
   where
-    coalgebra term = (NewField .: (extract term)) :< unwrap term
+    coalgebra term = (NewField :. (extract term)) :< unwrap term
 
 {-
 Catamorphism example -- add a new field to each term's Record fields
@@ -47,7 +47,7 @@ indexedTermCata :: [leaf] -> Term (Syntax leaf) (Record '[NewField, Range, Categ
 indexedTermCata childrenLeaves = cata algebra (indexedTerm childrenLeaves)
   where
     algebra :: CofreeF f (Record t) (Cofree f (Record (NewField : t))) -> Cofree f (Record (NewField : t))
-    algebra term = cofree $ (NewField .: (headF term)) :< tailF term
+    algebra term = cofree $ (NewField :. (headF term)) :< tailF term
 
 {-
 Anamorphism -- construct a Term from a string
@@ -58,25 +58,25 @@ representation.
 Example usage:
 
 stringToTermAna "indexed" =>
-  CofreeT (Identity ( (Range {start = 1, end = 10} .: MethodCall .: RNil)
+  CofreeT (Identity ( (Range {start = 1, end = 10} :. MethodCall :. Nil)
                       :<
                       Indexed
-                        [ CofreeT (Identity ( (Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf1" ) )
-                        , CofreeT (Identity ( (Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf2" ) )
-                        , CofreeT (Identity ( (Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf3" ) )
+                        [ CofreeT (Identity ( (Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf1" ) )
+                        , CofreeT (Identity ( (Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf2" ) )
+                        , CofreeT (Identity ( (Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf3" ) )
                         ] ))
 
   First step is to match against the "indexed" string and begin building up a Cofree Indexed structure:
 
-  CofreeT (Identity ( (Range 1 10 .: Category.MethodCall .: RNil) :< Indexed ["leaf1", "leaf2", "leaf3"] ) )
+  CofreeT (Identity ( (Range 1 10 :. Category.MethodCall :. Nil) :< Indexed ["leaf1", "leaf2", "leaf3"] ) )
 
   While building up the `Indexed` structure, we continue to recurse over the
   `Indexed` terms ["leaf1", "leaf2", "leaf3"]. These are pattern matched using
   the catch all `_` and default to `Leaf` Syntax shapes:
 
-  CofreeT (Identity ( (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf "leaf1" ) )
-  CofreeT (Identity ( (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf "leaf2" ) )
-  CofreeT (Identity ( (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf "leaf3" ) )
+  CofreeT (Identity ( (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf "leaf1" ) )
+  CofreeT (Identity ( (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf "leaf2" ) )
+  CofreeT (Identity ( (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf "leaf3" ) )
 
   These structures are substituted in place of ["leaf1", "leaf2", "leaf3"] in
   the new cofree `Indexed` structure, resulting in a expansion of all possible
@@ -86,8 +86,8 @@ stringToTermAna :: String -> Term (Syntax String) (Record '[Range, Category])
 stringToTermAna = ana coalgebra
   where
     coalgebra representation = case representation of
-      "indexed" -> (Range 1 10 .: Category.MethodCall .: RNil) :< Indexed ["leaf1", "leaf2", "leaf3"]
-      _ -> (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf representation
+      "indexed" -> (Range 1 10 :. Category.MethodCall :. Nil) :< Indexed ["leaf1", "leaf2", "leaf3"]
+      _ -> (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf representation
 
 {-
 Catamorphism -- construct a list of Strings from a recursive Term structure.
@@ -131,8 +131,8 @@ stringTermHylo = hylo algebra coalgebra
       (_ :< Indexed values) -> ["indexed"] <> Prologue.concat values
       _ -> ["unknown"]
     coalgebra stringRepresentation = case stringRepresentation of
-      "indexed" -> (Range 1 10 .: Category.MethodCall .: RNil) :< Indexed ["leaf1", "leaf2", "leaf3"]
-      _ -> (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf stringRepresentation
+      "indexed" -> (Range 1 10 :. Category.MethodCall :. Nil) :< Indexed ["leaf1", "leaf2", "leaf3"]
+      _ -> (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf stringRepresentation
 
 {-
 Paramorphism -- primitive recursion that maintains a reference to the original value and its computed value.
@@ -158,22 +158,22 @@ Example Usage:
 let terms = indexedTerm ["leaf1", "leaf2", "leaf3"]
 termPara terms = Recurse over the structure to start at the leaves (bottom up traversal):
 
-tuple3 = ( CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf3")), "leaf3" ) : []
+tuple3 = ( CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf3")), "leaf3" ) : []
 
 Continue the traversal from leaves to root:
 
-tuple2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf2")), "leaf2") : tuple3
+tuple2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf2")), "leaf2") : tuple3
 
-tuple1:2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf1" )), "leaf1") : tuple2:3
+tuple1:2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf1" )), "leaf1") : tuple2:3
 
 Compute the root:
-tupleIndexed:1:2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Indexed [])), "indexed" ) : tuple1:2:3
+tupleIndexed:1:2:3 = ( CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Indexed [])), "indexed" ) : tuple1:2:3
 
 Final shape:
-[ (CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Indexed []))  , "indexed")
-, (CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf1")), "leaf1")
-, (CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf2")), "leaf2")
-, (CofreeT (Identity ((Range {start = 1, end = 10} .: MethodCall .: RNil) :< Leaf "leaf3")), "leaf3")
+[ (CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Indexed []))  , "indexed")
+, (CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf1")), "leaf1")
+, (CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf2")), "leaf2")
+, (CofreeT (Identity ((Range {start = 1, end = 10} :. MethodCall :. Nil) :< Leaf "leaf3")), "leaf3")
 ]
 
 -}
@@ -183,4 +183,4 @@ termPara = para algebra
     algebra term = case term of
       (annotation :< Leaf representation) -> [(cofree (annotation :< Leaf representation), representation)]
       (annotation :< Indexed values) -> [(cofree (annotation :< Indexed []), "indexed")] <> (values >>= Prelude.snd)
-      _ -> [(cofree ((Range 1 10 .: Category.MethodCall .: RNil) :< Leaf "unknown"), "unknown")]
+      _ -> [(cofree ((Range 1 10 :. Category.MethodCall :. Nil) :< Leaf "unknown"), "unknown")]
diff --git a/src/FDoc/Term.hs b/src/FDoc/Term.hs
index 288c2fcbd..5f894f486 100644
--- a/src/FDoc/Term.hs
+++ b/src/FDoc/Term.hs
@@ -26,14 +26,14 @@ Example (from GHCi):
 
 > let leaf = leafTermF "example"
 > headF leaf
-> Range {start = 1, end = 10} .: MethodCall .: RNil
+> Range {start = 1, end = 10} :. MethodCall :. Nil
 > tailF leaf
 > Leaf "example"
 
 -}
 
 leafTermF :: leaf -> TermF (Syntax leaf) (Record '[Range, Category]) b
-leafTermF leaf = (Range 1 10 .: Category.MethodCall .: RNil) :< Leaf leaf
+leafTermF leaf = (Range 1 10 :. Category.MethodCall :. Nil) :< Leaf leaf
 
 {-
 
@@ -52,7 +52,7 @@ Example (from GHCi):
 
 > let leaf = leafTerm "example"
 > extract leaf
-> Range {start = 1, end = 10} .: MethodCall .: RNil
+> Range {start = 1, end = 10} :. MethodCall :. Nil
 > unwrap leaf
 > Leaf "example"
 
@@ -61,7 +61,7 @@ leafTerm :: leaf -> Cofree (Syntax leaf) (Record '[Range, Category])
 leafTerm = cofree . leafTermF
 
 indexedTermF :: [leaf] -> TermF (Syntax leaf) (Record '[Range, Category]) (Term (Syntax leaf) (Record '[Range, Category]))
-indexedTermF leaves = (Range 1 10 .: Category.MethodCall .: RNil) :< (Indexed (leafTerm <$> leaves))
+indexedTermF leaves = (Range 1 10 :. Category.MethodCall :. Nil) :< (Indexed (leafTerm <$> leaves))
 
 indexedTerm :: [leaf] -> Term (Syntax leaf) (Record '[Range, Category])
 indexedTerm leaves = cofree $ indexedTermF leaves
diff --git a/src/Language.hs b/src/Language.hs
index 4a395f484..49527f14f 100644
--- a/src/Language.hs
+++ b/src/Language.hs
@@ -56,7 +56,7 @@ termConstructor source sourceSpan category range children _ =
     _ -> S.Indexed children
   where
     withDefaultInfo syntax =
-      pure $! cofree ((range .: category .: sourceSpan .: RNil) :< syntax)
+      pure $! cofree ((range :. category :. sourceSpan :. Nil) :< syntax)
 
 toVarDecl :: (HasField fields Category) => Term (S.Syntax Text) (Record fields) -> Term (S.Syntax Text) (Record fields)
 toVarDecl child = cofree $ setCategory (extract child) VarDecl :< S.VarDecl child Nothing
diff --git a/src/Language/C.hs b/src/Language/C.hs
index cca133032..313752222 100644
--- a/src/Language/C.hs
+++ b/src/Language/C.hs
@@ -22,7 +22,7 @@ termConstructor source sourceSpan category range children _
   [] -> S.Leaf . toText $ slice range source
   _ -> S.Indexed children
   where
-    withDefaultInfo syntax = pure $! cofree ((range .: category .: sourceSpan .: RNil) :< syntax)
+    withDefaultInfo syntax = pure $! cofree ((range :. category :. sourceSpan :. Nil) :< syntax)
 
 categoryForCProductionName :: Text -> Category
 categoryForCProductionName = Other
diff --git a/src/Language/Go.hs b/src/Language/Go.hs
index e6768a990..25896a25f 100644
--- a/src/Language/Go.hs
+++ b/src/Language/Go.hs
@@ -236,10 +236,10 @@ termConstructor source sourceSpan category range children _ = pure $! case categ
       let ranges' = getField . extract <$> terms
           sourceSpans' = getField . extract <$> terms
       in
-      cofree ((unionRangesFrom originalRange ranges' .: category' .: unionSourceSpansFrom sourceSpan sourceSpans' .: RNil) :< syntax)
+      cofree ((unionRangesFrom originalRange ranges' :. category' :. unionSourceSpansFrom sourceSpan sourceSpans' :. Nil) :< syntax)
 
     withCategory category syntax =
-      cofree ((range .: category .: sourceSpan .: RNil) :< syntax)
+      cofree ((range :. category :. sourceSpan :. Nil) :< syntax)
 
     withDefaultInfo = withCategory category
 
diff --git a/src/Language/JavaScript.hs b/src/Language/JavaScript.hs
index b2eb1b4a9..588435129 100644
--- a/src/Language/JavaScript.hs
+++ b/src/Language/JavaScript.hs
@@ -105,8 +105,8 @@ termConstructor source sourceSpan category range children allChildren
   where
     withDefaultInfo syntax =
       pure $! case syntax of
-        S.MethodCall{} -> cofree ((range .:  MethodCall .: sourceSpan .: RNil) :< syntax)
-        _ -> cofree ((range .: category .: sourceSpan .: RNil) :< syntax)
+        S.MethodCall{} -> cofree ((range :.  MethodCall :. sourceSpan :. Nil) :< syntax)
+        _ -> cofree ((range :. category :. sourceSpan :. Nil) :< syntax)
 
 categoryForJavaScriptProductionName :: Text -> Category
 categoryForJavaScriptProductionName name = case name of
diff --git a/src/Language/Markdown.hs b/src/Language/Markdown.hs
index 62ed99fcb..3d314459c 100644
--- a/src/Language/Markdown.hs
+++ b/src/Language/Markdown.hs
@@ -19,7 +19,7 @@ cmarkParser SourceBlob{..} = pure . toTerm (totalRange source) (rangeToSourceSpa
             range = maybe within (sourceSpanToRange source . toSpan) position
             span = maybe withinSpan toSpan position
           in
-            cofree $ (range .: toCategory t .: span .: RNil) :< case t of
+            cofree $ (range :. toCategory t :. span :. Nil) :< case t of
           -- Leaves
           CODE text -> Leaf text
           TEXT text -> Leaf text
diff --git a/src/Language/Ruby.hs b/src/Language/Ruby.hs
index c1e71e1c3..c6cff83b3 100644
--- a/src/Language/Ruby.hs
+++ b/src/Language/Ruby.hs
@@ -124,7 +124,7 @@ termConstructor source sourceSpan category range children allChildren
   where
     withRecord record syntax = cofree (record :< syntax)
     withCategory category syntax =
-      cofree ((range .: category .: sourceSpan .: RNil) :< syntax)
+      cofree ((range :. category :. sourceSpan :. Nil) :< syntax)
     withDefaultInfo syntax = case syntax of
       S.MethodCall{} -> withCategory MethodCall syntax
       _ -> withCategory category syntax
diff --git a/src/Parse.hs b/src/Parse.hs
index 184081186..f1730dfef 100644
--- a/src/Parse.hs
+++ b/src/Parse.hs
@@ -81,7 +81,7 @@ parserForType mediaType = case languageForType mediaType of
 
 -- | Decorate a 'Term' using a function to compute the annotation values at every node.
 decorateTerm :: (Functor f) => TermDecorator f fields field -> Term f (Record fields) -> Term f (Record (field ': fields))
-decorateTerm decorator = cata $ \ term -> cofree ((decorator (extract <$> term) .: headF term) :< tailF term)
+decorateTerm decorator = cata $ \ term -> cofree ((decorator (extract <$> term) :. headF term) :< tailF term)
 
 -- | A function computing a value to decorate terms with. This can be used to cache synthesized attributes on terms.
 type TermDecorator f fields field = TermF f (Record fields) (Record (field ': fields)) -> field
@@ -101,8 +101,8 @@ lineByLineParser SourceBlob{..} = pure . cofree . root $ case foldl' annotateLea
   (leaves, _) -> cofree <$> leaves
   where
     lines = actualLines source
-    root children = (Range 0 (length source) .: Program .: rangeToSourceSpan source (Range 0 (length source)) .: RNil) :< Indexed children
-    leaf charIndex line = (Range charIndex (charIndex + T.length line) .: Program .: rangeToSourceSpan source (Range charIndex (charIndex + T.length line)) .: RNil) :< Leaf line
+    root children = (Range 0 (length source) :. Program :. rangeToSourceSpan source (Range 0 (length source)) :. Nil) :< Indexed children
+    leaf charIndex line = (Range charIndex (charIndex + T.length line) :. Program :. rangeToSourceSpan source (Range charIndex (charIndex + T.length line)) :. Nil) :< Leaf line
     annotateLeaves (accum, charIndex) line =
       (accum <> [ leaf charIndex (toText line) ] , charIndex + length line)
     toText = T.pack . Source.toString
diff --git a/src/Range.hs b/src/Range.hs
index d77fcddd4..73cb4b2b2 100644
--- a/src/Range.hs
+++ b/src/Range.hs
@@ -38,7 +38,7 @@ rangesAndWordsFrom startIndex string = fromMaybe [] $ take isWord <|> take isPun
       ([], _) -> Nothing
       (parsed, rest) -> Just . maybe identity (:) (transform parsed) $ rangesAndWordsFrom (endFor parsed) rest
     -- | Is this a word character?
-    -- | Word characters are defined as in [Ruby’s `\p{Word}` syntax](http://ruby-doc.org/core-2.1.1/Regexp.html#class-Regexp-label-Character+Properties), i.e.:
+    -- | Word characters are defined as in [Ruby’s `\p{Word}` syntax](http://ruby-doc.org/core-2.1.1/Regexp.html#class-Regexp-label-Character+Properties), i.e:.
     -- | > A member of one of the following Unicode general category _Letter_, _Mark_, _Number_, _Connector_Punctuation_
     isWord c = Char.isLetter c || Char.isNumber c || Char.isMark c || Char.generalCategory c == Char.ConnectorPunctuation
     isPunctuation c = not (Char.isSpace c || isWord c)
diff --git a/test/AlignmentSpec.hs b/test/AlignmentSpec.hs
index ef57f93a2..7303a232a 100644
--- a/test/AlignmentSpec.hs
+++ b/test/AlignmentSpec.hs
@@ -260,7 +260,7 @@ align :: Both (Source.Source Char) -> ConstructibleFree (Patch (Term (Syntax Str
 align sources = PrettyDiff sources . fmap (fmap (getRange &&& identity)) . alignDiff sources . deconstruct
 
 info :: Int -> Int -> Record '[Range]
-info start end = Range start end .: RNil
+info start end = Range start end :. Nil
 
 prettyDiff :: Both (Source.Source Char) -> [Join These (ConstructibleFree (SplitPatch (Term (Syntax String) (Record '[Range]))) (Record '[Range]))] -> PrettyDiff (SplitDiff (Syntax String) (Record '[Range]))
 prettyDiff sources = PrettyDiff sources . fmap (fmap ((getRange &&& identity) . deconstruct))
diff --git a/test/Data/RandomWalkSimilarity/Spec.hs b/test/Data/RandomWalkSimilarity/Spec.hs
index e25680b43..79c01aefe 100644
--- a/test/Data/RandomWalkSimilarity/Spec.hs
+++ b/test/Data/RandomWalkSimilarity/Spec.hs
@@ -36,12 +36,12 @@ spec = parallel $ do
     prop "produces correct diffs" $
       \ (as, bs) -> let tas = decorate <$> (unListableF <$> as :: [SyntaxTerm String '[Category]])
                         tbs = decorate <$> (unListableF <$> bs :: [SyntaxTerm String '[Category]])
-                        root = cofree . ((Program .: RNil) :<) . Indexed
-                        diff = wrap (pure (Program .: RNil) :< Indexed (stripDiff <$> rws compare getLabel tas tbs)) in
+                        root = cofree . ((Program :. Nil) :<) . Indexed
+                        diff = wrap (pure (Program :. Nil) :< Indexed (stripDiff <$> rws compare getLabel tas tbs)) in
         (beforeTerm diff, afterTerm diff) `shouldBe` (Just (root (stripTerm <$> tas)), Just (root (stripTerm <$> tbs)))
 
     it "produces unbiased insertions within branches" $
-      let (a, b) = (decorate (cofree ((StringLiteral .: RNil) :< Indexed [ cofree ((StringLiteral .: RNil) :< Leaf ("a" :: Text)) ])), decorate (cofree ((StringLiteral .: RNil) :< Indexed [ cofree ((StringLiteral .: RNil) :< Leaf "b") ]))) in
+      let (a, b) = (decorate (cofree ((StringLiteral :. Nil) :< Indexed [ cofree ((StringLiteral :. Nil) :< Leaf ("a" :: Text)) ])), decorate (cofree ((StringLiteral :. Nil) :< Indexed [ cofree ((StringLiteral :. Nil) :< Leaf "b") ]))) in
       fmap stripDiff (rws compare getLabel [ b ] [ a, b ]) `shouldBe` fmap stripDiff [ inserting a, copying b ]
 
   where compare :: (HasField fields Category, Functor f, Eq (Cofree f Category)) => Term f (Record fields) -> Term f (Record fields) -> Maybe (Diff f (Record fields))
diff --git a/test/DiffSummarySpec.hs b/test/DiffSummarySpec.hs
index 5f7e54d57..d1daa1ef4 100644
--- a/test/DiffSummarySpec.hs
+++ b/test/DiffSummarySpec.hs
@@ -27,10 +27,10 @@ sourceSpanBetween :: (Int, Int) -> (Int, Int) -> SourceSpan
 sourceSpanBetween (s1, e1) (s2, e2) = SourceSpan (SourcePos s1 e1) (SourcePos s2 e2)
 
 arrayInfo :: Record '[Category, Range, SourceSpan]
-arrayInfo = ArrayLiteral .: Range 0 3 .: sourceSpanBetween (1, 1) (1, 5) .: RNil
+arrayInfo = ArrayLiteral :. Range 0 3 :. sourceSpanBetween (1, 1) (1, 5) :. Nil
 
 literalInfo :: Record '[Category, Range, SourceSpan]
-literalInfo = StringLiteral .: Range 1 2 .: sourceSpanBetween (1, 2) (1, 4) .: RNil
+literalInfo = StringLiteral :. Range 1 2 :. sourceSpanBetween (1, 2) (1, 4) :. Nil
 
 testDiff :: Diff (Syntax Text) (Record '[Category, Range, SourceSpan])
 testDiff = free $ Free (pure arrayInfo :< Indexed [ free $ Pure (Insert (cofree $ literalInfo :< Leaf "\"a\"")) ])
diff --git a/test/InterpreterSpec.hs b/test/InterpreterSpec.hs
index 8435314b3..67d8b7f1e 100644
--- a/test/InterpreterSpec.hs
+++ b/test/InterpreterSpec.hs
@@ -2,7 +2,7 @@
 module InterpreterSpec where
 
 import Category
-import Data.Functor.Foldable
+import Data.Functor.Foldable hiding (Nil)
 import Data.Functor.Listable
 import Data.RandomWalkSimilarity
 import Data.Record
@@ -25,8 +25,8 @@ spec = parallel $ do
     let decorate = defaultFeatureVectorDecorator (category . headF)
     let compare = (==) `on` category . extract
     it "returns a replacement when comparing two unicode equivalent terms" $
-      let termA = cofree $ (StringLiteral .: RNil) :< Leaf ("t\776" :: String)
-          termB = cofree $ (StringLiteral .: RNil) :< Leaf "\7831" in
+      let termA = cofree $ (StringLiteral :. Nil) :< Leaf ("t\776" :: String)
+          termB = cofree $ (StringLiteral :. Nil) :< Leaf "\7831" in
           stripDiff (diffTerms wrap compare diffCost getLabel (decorate termA) (decorate termB)) `shouldBe` replacing termA termB
 
     prop "produces correct diffs" $
@@ -39,6 +39,6 @@ spec = parallel $ do
                  diffCost diff `shouldBe` 0
 
     it "produces unbiased insertions within branches" $
-      let term s = decorate (cofree ((StringLiteral .: RNil) :< Indexed [ cofree ((StringLiteral .: RNil) :< Leaf s) ]))
-          root = cofree . ((pure 0 .: Program .: RNil) :<) . Indexed in
-      stripDiff (diffTerms wrap compare diffCost getLabel (root [ term "b" ]) (root [ term "a", term "b" ])) `shouldBe` wrap (pure (Program .: RNil) :< Indexed [ inserting (stripTerm (term "a")), cata wrap (fmap pure (stripTerm (term "b"))) ])
+      let term s = decorate (cofree ((StringLiteral :. Nil) :< Indexed [ cofree ((StringLiteral :. Nil) :< Leaf s) ]))
+          root = cofree . ((pure 0 :. Program :. Nil) :<) . Indexed in
+      stripDiff (diffTerms wrap compare diffCost getLabel (root [ term "b" ]) (root [ term "a", term "b" ])) `shouldBe` wrap (pure (Program :. Nil) :< Indexed [ inserting (stripTerm (term "a")), cata wrap (fmap pure (stripTerm (term "b"))) ])
diff --git a/test/PatchOutputSpec.hs b/test/PatchOutputSpec.hs
index fbe164da2..c0d674979 100644
--- a/test/PatchOutputSpec.hs
+++ b/test/PatchOutputSpec.hs
@@ -14,4 +14,4 @@ spec :: Spec
 spec = parallel $ do
   describe "hunks" $ do
     it "empty diffs have empty hunks" $
-        hunks (wrap $ pure (Range 0 0 .: RNil) :< Leaf ("" :: Text)) (both (SourceBlob (fromList "") "abcde" "path2.txt" (Just defaultPlainBlob)) (SourceBlob (fromList "") "xyz" "path2.txt" (Just defaultPlainBlob))) `shouldBe` [Hunk {offset = pure 0, changes = [], trailingContext = []}]
+        hunks (wrap $ pure (Range 0 0 :. Nil) :< Leaf ("" :: Text)) (both (SourceBlob (fromList "") "abcde" "path2.txt" (Just defaultPlainBlob)) (SourceBlob (fromList "") "xyz" "path2.txt" (Just defaultPlainBlob))) `shouldBe` [Hunk {offset = pure 0, changes = [], trailingContext = []}]