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diff --git a/users/grfn/xanthous/src/Data/Aeson/Generic/DerivingVia.hs b/users/grfn/xanthous/src/Data/Aeson/Generic/DerivingVia.hs
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index e89fcd621157..000000000000
--- a/users/grfn/xanthous/src/Data/Aeson/Generic/DerivingVia.hs
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@@ -1,168 +0,0 @@
-{-# LANGUAGE ConstraintKinds, DataKinds, DeriveGeneric, DerivingVia    #-}
-{-# LANGUAGE ExplicitNamespaces, FlexibleContexts, FlexibleInstances   #-}
-{-# LANGUAGE GADTs, GeneralizedNewtypeDeriving, MultiParamTypeClasses  #-}
-{-# LANGUAGE PolyKinds, ScopedTypeVariables, StandaloneDeriving        #-}
-{-# LANGUAGE TypeApplications, TypeFamilies, TypeInType, TypeOperators #-}
-{-# LANGUAGE UndecidableInstances                                      #-}
-{-# OPTIONS_GHC -Wall #-}
--- | https://gist.github.com/konn/27c00f784dd883ec2b90eab8bc84a81d
-module Data.Aeson.Generic.DerivingVia
-     ( StrFun(..), Setting(..), SumEncoding'(..), DefaultOptions, WithOptions(..)
-     , -- Utility type synonyms to save ticks (') before promoted data constructors
-       type Drop, type CamelTo2, type UserDefined
-     , type TaggedObj, type UntaggedVal, type ObjWithSingleField, type TwoElemArr
-     , type FieldLabelModifier
-     , type ConstructorTagModifier
-     , type AllNullaryToStringTag
-     , type OmitNothingFields
-     , type SumEnc
-     , type UnwrapUnaryRecords
-     , type TagSingleConstructors
-     )
-  where
-
-import           Prelude
-import           Data.Aeson      (FromJSON (..), GFromJSON, GToJSON,
-                                  ToJSON (..))
-import           Data.Aeson      (Options (..), Zero, camelTo2,
-                                  genericParseJSON)
-import           Data.Aeson      (defaultOptions, genericToJSON)
-import qualified Data.Aeson      as Aeson
-import           Data.Kind       (Constraint, Type)
-import           Data.Proxy      (Proxy (..))
-import           Data.Reflection (Reifies (..))
-import           GHC.Generics    (Generic, Rep)
-import           GHC.TypeLits    (KnownNat, KnownSymbol, natVal, symbolVal)
-import           GHC.TypeLits    (Nat, Symbol)
-
-newtype WithOptions options a = WithOptions { runWithOptions :: a }
-
-data StrFun = Drop     Nat
-            | CamelTo2 Symbol
-            | forall p. UserDefined p
-
-type Drop = 'Drop
-type CamelTo2 = 'CamelTo2
-type UserDefined = 'UserDefined
-
-type family Demoted a where
-  Demoted Symbol  = String
-  Demoted StrFun  = String -> String
-  Demoted [a]     = [Demoted a]
-  Demoted Setting = Options -> Options
-  Demoted SumEncoding' = Aeson.SumEncoding
-  Demoted a = a
-
-data SumEncoding' = TaggedObj {tagFieldName' :: Symbol, contentsFieldName :: Symbol }
-                  | UntaggedVal
-                  | ObjWithSingleField
-                  | TwoElemArr
-
-type TaggedObj          = 'TaggedObj
-type UntaggedVal        = 'UntaggedVal
-type ObjWithSingleField = 'ObjWithSingleField
-type TwoElemArr         = 'TwoElemArr
-
-data Setting = FieldLabelModifier     [StrFun]
-             | ConstructorTagModifier [StrFun]
-             | AllNullaryToStringTag  Bool
-             | OmitNothingFields      Bool
-             | SumEnc                 SumEncoding'
-             | UnwrapUnaryRecords     Bool
-             | TagSingleConstructors  Bool
-
-type FieldLabelModifier     = 'FieldLabelModifier
-type ConstructorTagModifier = 'ConstructorTagModifier
--- | If 'True' the constructors of a datatype, with all nullary constructors,
--- will be encoded to just a string with the constructor tag. If 'False' the
--- encoding will always follow the 'SumEncoding'.
-type AllNullaryToStringTag  = 'AllNullaryToStringTag
-type OmitNothingFields      = 'OmitNothingFields
-type SumEnc                 = 'SumEnc
--- | Hide the field name when a record constructor has only one field, like a
--- newtype.
-type UnwrapUnaryRecords     = 'UnwrapUnaryRecords
--- | Encode types with a single constructor as sums, so that
--- 'AllNullaryToStringTag' and 'SumEncoding' apply.
-type TagSingleConstructors  = 'TagSingleConstructors
-
-class Demotable (a :: k) where
-  demote :: proxy a -> Demoted k
-
-type All :: (Type -> Constraint) -> [Type] -> Constraint
-type family All p xs where
-  All p '[] = ()
-  All p (x ': xs) = (p x, All p xs)
-
-instance Reifies f (String -> String) => Demotable ('UserDefined f) where
-  demote _ = reflect @f Proxy
-
-instance KnownSymbol sym => Demotable sym where
-  demote = symbolVal
-
-instance (KnownSymbol s, KnownSymbol t) => Demotable ('TaggedObj s t) where
-  demote _ = Aeson.TaggedObject (symbolVal @s Proxy) (symbolVal @t Proxy)
-
-instance Demotable 'UntaggedVal where
-  demote _ = Aeson.UntaggedValue
-
-instance Demotable 'ObjWithSingleField where
-  demote _ = Aeson.ObjectWithSingleField
-
-instance Demotable 'TwoElemArr where
-  demote _ = Aeson.TwoElemArray
-
-instance Demotable xs => Demotable ('FieldLabelModifier xs) where
-  demote _ o = o { fieldLabelModifier = foldr (.) id (demote (Proxy @xs)) }
-
-instance Demotable xs => Demotable ('ConstructorTagModifier xs) where
-  demote _ o = o { constructorTagModifier = foldr (.) id (demote (Proxy @xs)) }
-
-instance Demotable b => Demotable ('AllNullaryToStringTag b) where
-  demote _ o = o { allNullaryToStringTag = demote (Proxy @b) }
-
-instance Demotable b => Demotable ('OmitNothingFields b) where
-  demote _ o = o { omitNothingFields = demote (Proxy @b) }
-
-instance Demotable b => Demotable ('UnwrapUnaryRecords b) where
-  demote _ o = o { unwrapUnaryRecords = demote (Proxy @b) }
-
-instance Demotable b => Demotable ('TagSingleConstructors b) where
-  demote _ o = o { tagSingleConstructors = demote (Proxy @b) }
-
-instance Demotable b => Demotable ('SumEnc b) where
-  demote _ o = o { sumEncoding = demote (Proxy @b) }
-
-instance Demotable 'True where
-  demote _ = True
-
-instance Demotable 'False where
-  demote _ = False
-
-instance KnownNat n => Demotable ('Drop n) where
-  demote _ = drop (fromIntegral $ natVal (Proxy :: Proxy n))
-
-instance KnownSymbol sym => Demotable ('CamelTo2 sym) where
-  demote _ = camelTo2 $ head $ symbolVal @sym Proxy
-
-instance {-# OVERLAPPING #-} Demotable ('[] :: [k]) where
-  demote _ = []
-
-instance (Demotable (x :: k), Demotable (xs :: [k])) => Demotable (x ': xs) where
-  demote _ = demote (Proxy @x) : demote (Proxy @xs)
-
-type DefaultOptions = ('[] :: [Setting])
-
-reflectOptions :: forall xs proxy. Demotable (xs :: [Setting]) => proxy xs -> Options
-reflectOptions pxy = foldr (.) id (demote pxy) defaultOptions
-
-instance (Demotable (options :: [Setting])) => Reifies options Options where
-  reflect = reflectOptions
-
-instance (Generic a, GToJSON Zero (Rep a), Reifies (options :: k) Options)
-       => ToJSON (WithOptions options a) where
-  toJSON = genericToJSON (reflect (Proxy @options)) . runWithOptions
-
-instance (Generic a, GFromJSON Zero (Rep a), Reifies (options :: k) Options)
-       => FromJSON (WithOptions options a) where
-  parseJSON = fmap WithOptions . genericParseJSON (reflect (Proxy @options))