diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # Changelog for persistent
 
+## 2.13.0.2
+
+* [#1265](https://github.com/yesodweb/persistent/pull/1265)
+    * Support GHC 9
+
 ## 2.13.0.1
 
 * [#1268](https://github.com/yesodweb/persistent/pull/1268)
diff --git a/Database/Persist/Class/PersistConfig.hs b/Database/Persist/Class/PersistConfig.hs
--- a/Database/Persist/Class/PersistConfig.hs
+++ b/Database/Persist/Class/PersistConfig.hs
@@ -6,12 +6,13 @@
 import Data.Aeson (Value (Object))
 import Data.Aeson.Types (Parser)
 import qualified Data.HashMap.Strict as HashMap
+import Data.Kind (Type)
 
 -- | Represents a value containing all the configuration options for a specific
 -- backend. This abstraction makes it easier to write code that can easily swap
 -- backends.
 class PersistConfig c where
-    type PersistConfigBackend c :: (* -> *) -> * -> *
+    type PersistConfigBackend c :: (Type -> Type) -> Type -> Type
     type PersistConfigPool c
 
     -- | Load the config settings from a 'Value', most likely taken from a YAML
diff --git a/Database/Persist/Class/PersistEntity.hs b/Database/Persist/Class/PersistEntity.hs
--- a/Database/Persist/Class/PersistEntity.hs
+++ b/Database/Persist/Class/PersistEntity.hs
@@ -49,7 +49,6 @@
 import qualified Data.HashMap.Strict as HM
 import Data.List.NonEmpty (NonEmpty(..))
 import Data.Maybe (isJust)
-import Data.Monoid (mappend)
 import Data.Text (Text)
 import qualified Data.Text as T
 import qualified Data.Text.Encoding as TE
@@ -58,6 +57,7 @@
 import GHC.Generics
 import GHC.OverloadedLabels
 import GHC.TypeLits
+import Data.Kind (Type)
 
 import Database.Persist.Class.PersistField
 import Database.Persist.Names
@@ -102,7 +102,7 @@
     -- As of @persistent-2.11.0.0@, it's possible to use the @OverloadedLabels@
     -- language extension to refer to 'EntityField' values polymorphically. See
     -- the documentation on 'SymbolToField' for more information.
-    data EntityField record :: * -> *
+    data EntityField record :: Type -> Type
     -- | Return meta-data for a given 'EntityField'.
     persistFieldDef :: EntityField record typ -> FieldDef
     -- | A meta-operation to get the database fields of a record.
@@ -317,7 +317,7 @@
         _ -> error $ T.unpack $ errMsg "expected PersistMap"
 
     fromPersistValue (PersistMap alist) = case after of
-        [] -> Left $ errMsg $ "did not find " `Data.Monoid.mappend` idField `mappend` " field"
+        [] -> Left $ errMsg $ "did not find " `mappend` idField `mappend` " field"
         ("_id", kv):afterRest ->
             fromPersistValue (PersistMap (before ++ afterRest)) >>= \record ->
                 keyFromValues [kv] >>= \k ->
diff --git a/Database/Persist/Class/PersistField.hs b/Database/Persist/Class/PersistField.hs
--- a/Database/Persist/Class/PersistField.hs
+++ b/Database/Persist/Class/PersistField.hs
@@ -20,7 +20,6 @@
 import Data.Int (Int8, Int16, Int32, Int64)
 import qualified Data.IntMap as IM
 import qualified Data.Map as M
-import Data.Monoid ((<>))
 import qualified Data.Set as S
 import Data.Text (Text)
 import qualified Data.Text as T
diff --git a/Database/Persist/Quasi/Internal.hs b/Database/Persist/Quasi/Internal.hs
--- a/Database/Persist/Quasi/Internal.hs
+++ b/Database/Persist/Quasi/Internal.hs
@@ -924,7 +924,7 @@
           | n == "Foreign" =
               (Nothing, Nothing, Nothing, Just $ takeForeign ps entityName rest)
           | n == "Primary" =
-              (Nothing, Just $ takeComposite ps defNames rest, Nothing, Nothing)
+              (Nothing, Just $ takeComposite defNames rest, Nothing, Nothing)
           | n == "Id"      =
               (Just $ takeId ps entityName rest, Nothing, Nothing, Nothing)
           | otherwise      =
@@ -1012,11 +1012,10 @@
     deriving (Show, Lift)
 
 takeComposite
-    :: PersistSettings
-    -> [FieldNameHS]
+    :: [FieldNameHS]
     -> [Text]
     -> UnboundCompositeDef
-takeComposite ps fields pkcols =
+takeComposite fields pkcols =
     UnboundCompositeDef
         { unboundCompositeCols =
             map (getDef fields) cols
diff --git a/Database/Persist/Sql/Class.hs b/Database/Persist/Sql/Class.hs
--- a/Database/Persist/Sql/Class.hs
+++ b/Database/Persist/Sql/Class.hs
@@ -22,7 +22,6 @@
 import qualified Data.IntMap as IM
 import qualified Data.Map as M
 import Data.Maybe (fromMaybe)
-import Data.Monoid ((<>))
 import Data.Proxy (Proxy(..))
 import qualified Data.Set as S
 import Data.Text (Text, intercalate, pack)
diff --git a/Database/Persist/Sql/Orphan/PersistQuery.hs b/Database/Persist/Sql/Orphan/PersistQuery.hs
--- a/Database/Persist/Sql/Orphan/PersistQuery.hs
+++ b/Database/Persist/Sql/Orphan/PersistQuery.hs
@@ -23,7 +23,7 @@
 import Data.Int (Int64)
 import Data.List (find, inits, transpose)
 import Data.Maybe (isJust)
-import Data.Monoid (Monoid(..), (<>))
+import Data.Monoid (Monoid(..))
 import Data.Text (Text)
 import qualified Data.Text as T
 import Data.Foldable (toList)
diff --git a/Database/Persist/Sql/Orphan/PersistStore.hs b/Database/Persist/Sql/Orphan/PersistStore.hs
--- a/Database/Persist/Sql/Orphan/PersistStore.hs
+++ b/Database/Persist/Sql/Orphan/PersistStore.hs
@@ -30,7 +30,6 @@
 import Data.List (find, nubBy)
 import qualified Data.Map as Map
 import Data.Maybe (isJust)
-import Data.Monoid (mappend, (<>))
 import Data.Text (Text, unpack)
 import qualified Data.Text as T
 import Data.Void (Void)
diff --git a/Database/Persist/Sql/Orphan/PersistUnique.hs b/Database/Persist/Sql/Orphan/PersistUnique.hs
--- a/Database/Persist/Sql/Orphan/PersistUnique.hs
+++ b/Database/Persist/Sql/Orphan/PersistUnique.hs
@@ -10,7 +10,6 @@
 import qualified Data.Conduit.List as CL
 import Data.Function (on)
 import Data.List (nubBy)
-import Data.Monoid (mappend)
 import qualified Data.Text as T
 import Data.Foldable (toList)
 
diff --git a/Database/Persist/Sql/Run.hs b/Database/Persist/Sql/Run.hs
--- a/Database/Persist/Sql/Run.hs
+++ b/Database/Persist/Sql/Run.hs
@@ -10,7 +10,6 @@
 import Control.Monad.Trans.Resource
 import Data.Acquire (Acquire, ReleaseType(..), mkAcquireType, with)
 import Data.IORef (readIORef)
-import Data.Pool (Pool)
 import Data.Pool as P
 import qualified Data.Map as Map
 import qualified Data.Text as T
diff --git a/Database/Persist/Sql/Types.hs b/Database/Persist/Sql/Types.hs
--- a/Database/Persist/Sql/Types.hs
+++ b/Database/Persist/Sql/Types.hs
@@ -8,8 +8,6 @@
     , ConnectionPoolConfig(..)
     ) where
 
-import Database.Persist.Types.Base (FieldCascade)
-
 import Control.Exception (Exception(..))
 import Control.Monad.Logger (NoLoggingT)
 import Control.Monad.Trans.Reader (ReaderT(..))
diff --git a/Database/Persist/Sql/Types/Internal.hs b/Database/Persist/Sql/Types/Internal.hs
--- a/Database/Persist/Sql/Types/Internal.hs
+++ b/Database/Persist/Sql/Types/Internal.hs
@@ -29,7 +29,6 @@
 
 import Control.Monad.Trans.Class (lift)
 import Control.Monad.Trans.Reader (ReaderT, runReaderT, ask)
-import Data.Monoid ((<>))
 
 import Database.Persist.Class
     ( HasPersistBackend (..)
diff --git a/Database/Persist/Sql/Util.hs b/Database/Persist/Sql/Util.hs
--- a/Database/Persist/Sql/Util.hs
+++ b/Database/Persist/Sql/Util.hs
@@ -22,7 +22,6 @@
 
 import Data.List.NonEmpty (NonEmpty(..))
 import qualified Data.Maybe as Maybe
-import Data.Monoid ((<>))
 import Data.Text (Text, pack)
 import qualified Data.Text as T
 
diff --git a/Database/Persist/SqlBackend/Internal/IsolationLevel.hs b/Database/Persist/SqlBackend/Internal/IsolationLevel.hs
--- a/Database/Persist/SqlBackend/Internal/IsolationLevel.hs
+++ b/Database/Persist/SqlBackend/Internal/IsolationLevel.hs
@@ -1,7 +1,6 @@
 module Database.Persist.SqlBackend.Internal.IsolationLevel where
 
 import Data.String (IsString(..))
-import Data.Monoid ((<>)) -- TODO: remove when GHC-8.2 support is dropped
 
 -- | Please refer to the documentation for the database in question for a full
 -- overview of the semantics of the varying isloation levels
diff --git a/Database/Persist/TH.hs b/Database/Persist/TH.hs
--- a/Database/Persist/TH.hs
+++ b/Database/Persist/TH.hs
@@ -97,7 +97,6 @@
 import qualified Data.List.NonEmpty as NEL
 import qualified Data.Map as M
 import Data.Maybe (fromMaybe, isJust, listToMaybe, mapMaybe)
-import Data.Monoid (mappend, mconcat, (<>))
 import Data.Proxy (Proxy(Proxy))
 import Data.Text (Text, concat, cons, pack, stripSuffix, uncons, unpack)
 import qualified Data.Text as T
@@ -124,7 +123,7 @@
 import Database.Persist.Sql
        (Migration, PersistFieldSql, SqlBackend, migrate, sqlType)
 
-import Database.Persist.EntityDef.Internal (EntityDef(..), EntityIdDef(..))
+import Database.Persist.EntityDef.Internal (EntityDef(..))
 import Database.Persist.ImplicitIdDef (autoIncrementingInteger)
 import Database.Persist.ImplicitIdDef.Internal
 
@@ -714,7 +713,7 @@
     Left Nothing
 mEmbedded ents (FTTypeCon Nothing (EntityNameHS -> name)) =
     maybe (Left Nothing) (\_ -> Right name) $ M.lookup name ents
-mEmbedded ents (FTTypePromoted (EntityNameHS -> name)) =
+mEmbedded _ (FTTypePromoted _) =
     Left Nothing
 mEmbedded ents (FTList x) =
     mEmbedded ents x
@@ -1026,9 +1025,15 @@
         )
 
     (nameFinal, paramsFinal)
-        | mpsGeneric mps = (mkEntityDefGenericName entDef, [PlainTV backendName])
-        | otherwise = (mkEntityDefName entDef, [])
+        | mpsGeneric mps =
+            ( mkEntityDefGenericName entDef
+            , [ mkPlainTV backendName
+              ]
+            )
 
+        | otherwise =
+            (mkEntityDefName entDef, [])
+
     cols :: [VarBangType]
     cols = do
         fieldDef <- getUnboundFieldDefs entDef
@@ -1913,8 +1918,8 @@
         sT = mkST backend1
         tT = mkST backend2
         t1 `arrow` t2 = ArrowT `AppT` t1 `AppT` t2
-        vars = PlainTV fT
-             : (if mpsGeneric mps then [PlainTV backend1{-, PlainTV backend2-}] else [])
+        vars = mkForallTV fT
+             : (if mpsGeneric mps then [mkForallTV backend1{-, PlainTV backend2-}] else [])
     return
         [ SigD lensName $ ForallT vars [mkClassP ''Functor [VarT fT]] $
             (aT `arrow` (VarT fT `AppT` bT)) `arrow`
@@ -1933,6 +1938,33 @@
             ]
         ]
 
+#if MIN_VERSION_template_haskell(2,17,0)
+mkPlainTV
+    :: Name
+    -> TyVarBndr ()
+mkPlainTV n = PlainTV n ()
+
+mkDoE :: [Stmt] -> Exp
+mkDoE stmts = DoE Nothing stmts
+
+mkForallTV :: Name -> TyVarBndr Specificity
+mkForallTV n = PlainTV n SpecifiedSpec
+#else
+
+mkDoE :: [Stmt] -> Exp
+mkDoE = DoE
+
+mkPlainTV
+    :: Name
+    -> TyVarBndr
+mkPlainTV = PlainTV
+
+mkForallTV
+    :: Name
+    -> TyVarBndr
+mkForallTV = mkPlainTV
+#endif
+
 mkForeignKeysComposite
     :: MkPersistSettings
     -> UnboundEntityDef
@@ -2168,7 +2200,7 @@
             ]
             (ConT ''DeleteCascade `AppT` entityT `AppT` backendT)
             [ FunD 'deleteCascade
-                [normalClause [VarP key] (DoE stmts)]
+                [normalClause [VarP key] (mkDoE stmts)]
             ]
 
 -- | Creates a declaration for the @['EntityDef']@ from the @persistent@
diff --git a/bench/Main.hs b/bench/Main.hs
--- a/bench/Main.hs
+++ b/bench/Main.hs
@@ -1,12 +1,14 @@
+{-# LANGUAGE BangPatterns #-}
 {-# LANGUAGE CPP #-}
 {-# LANGUAGE TemplateHaskell #-}
+
 {-# OPTIONS_GHC -Wno-orphans #-}
+
 module Main (main) where
 
 import Control.DeepSeq
-import Control.DeepSeq.Generics
 import Criterion.Main
-import Data.Text                  (Text)
+import Data.Text (Text)
 import Language.Haskell.TH
 import Language.Haskell.TH.Syntax
 
@@ -17,7 +19,7 @@
 main :: IO ()
 main = defaultMain
     [ bgroup "mkPersist"
-        [ bench "From File" $ nfIO $ mkPersist' $(persistFileWith lowerCaseSettings "bench/models-slowly")
+        [ -- bench "From File" $ nfIO $ mkPersist' $(persistFileWith lowerCaseSettings "bench/models-slowly")
         -- , bgroup "Non-Null Fields"
         --    [ bgroup "Increasing model count"
         --        [ bench "1x10" $ nfIO $ mkPersist' $( parseReferencesQ (mkModels 10 10))
@@ -55,137 +57,146 @@
 
 -- Orphan instances for NFData Template Haskell types
 instance NFData Overlap where
-    rnf = genericRnf
 
+
 instance NFData AnnTarget where
-    rnf = genericRnf
+
 instance NFData RuleBndr where
-    rnf = genericRnf
 
+
 instance NFData Role where
-    rnf = genericRnf
 
+
 instance NFData Phases where
-    rnf = genericRnf
 
+
 instance NFData InjectivityAnn where
-    rnf = genericRnf
 
+
 instance NFData FamilyResultSig where
-    rnf = genericRnf
 
+
 instance NFData RuleMatch where
-    rnf = genericRnf
 
+
 instance NFData TypeFamilyHead where
-    rnf = genericRnf
 
+
 instance NFData TySynEqn where
-    rnf = genericRnf
 
+
 instance NFData Inline where
-    rnf = genericRnf
 
+
 instance NFData Pragma where
-    rnf = genericRnf
 
+
 instance NFData FixityDirection where
-    rnf = genericRnf
 
+
 instance NFData Safety where
-    rnf = genericRnf
 
+
 instance NFData Fixity where
-    rnf = genericRnf
 
+
 instance NFData Callconv where
-    rnf = genericRnf
 
+
 instance NFData Foreign where
-    rnf = genericRnf
 
+
 instance NFData SourceStrictness where
-    rnf = genericRnf
 
+
 instance NFData SourceUnpackedness where
-    rnf = genericRnf
 
+
 instance NFData FunDep where
-    rnf = genericRnf
 
+
 instance NFData Bang where
-    rnf = genericRnf
 
+
 #if MIN_VERSION_template_haskell(2,12,0)
 instance NFData PatSynDir where
-    rnf = genericRnf
 
+
 instance NFData PatSynArgs where
-    rnf = genericRnf
 
+
 instance NFData DerivStrategy where
-    rnf = genericRnf
 
+
 instance NFData DerivClause where
-    rnf = genericRnf
+
 #endif
 
 instance NFData Con where
-    rnf = genericRnf
 
+
 instance NFData Range where
-    rnf = genericRnf
 
+
 instance NFData Clause where
-    rnf = genericRnf
 
+
 instance NFData PkgName where
-    rnf = genericRnf
 
+
 instance NFData Dec where
-    rnf = genericRnf
 
+
 instance NFData Stmt where
-    rnf = genericRnf
 
+
 instance NFData TyLit where
-    rnf = genericRnf
 
+
 instance NFData NameSpace where
-    rnf = genericRnf
 
+
 instance NFData Body where
-    rnf = genericRnf
 
+
 instance NFData Guard where
-    rnf = genericRnf
 
+
 instance NFData Match where
-    rnf = genericRnf
 
+
 instance NFData ModName where
-    rnf = genericRnf
 
+
 instance NFData Pat where
-    rnf = genericRnf
 
+#if MIN_VERSION_template_haskell(2,16,0)
+instance NFData Bytes where
+    rnf !_ = ()
+#endif
+
+#if MIN_VERSION_template_haskell(2,17,0)
+instance NFData a => NFData (TyVarBndr a) where
+
+instance NFData Specificity
+#else
 instance NFData TyVarBndr where
-    rnf = genericRnf
 
+#endif
+
 instance NFData NameFlavour where
-    rnf = genericRnf
 
+
 instance NFData Type where
-    rnf = genericRnf
 
+
 instance NFData Exp where
-    rnf = genericRnf
 
+
 instance NFData Lit where
-    rnf = genericRnf
 
 instance NFData OccName where
-    rnf = genericRnf
 
+
 instance NFData Name where
-    rnf = genericRnf
+
diff --git a/bench/Models.hs b/bench/Models.hs
--- a/bench/Models.hs
+++ b/bench/Models.hs
@@ -5,10 +5,13 @@
 import qualified Data.Text as Text
 
 import Database.Persist.Quasi
+import Database.Persist.Quasi.Internal
 import Database.Persist.TH
 import Database.Persist.Sql
 
-mkPersist' :: [EntityDef] -> IO [Dec]
+-- TODO: we use lookupName and reify etc which breaks in IO. somehow need to
+-- test this out elsewise
+mkPersist' :: [UnboundEntityDef] -> IO [Dec]
 mkPersist' = runQ . mkPersist sqlSettings
 
 parseReferences' :: String -> IO Exp
diff --git a/persistent.cabal b/persistent.cabal
--- a/persistent.cabal
+++ b/persistent.cabal
@@ -1,5 +1,5 @@
 name:            persistent
-version:         2.13.0.1
+version:         2.13.0.2
 license:         MIT
 license-file:    LICENSE
 author:          Michael Snoyman <michael@snoyman.com>
@@ -166,6 +166,8 @@
         Database.Persist.TH.ForeignRefSpec
         Database.Persist.TH.ImplicitIdColSpec
         Database.Persist.TH.JsonEncodingSpec
+        Database.Persist.TH.KindEntitiesSpec
+        Database.Persist.TH.KindEntitiesSpecImports
         Database.Persist.TH.MigrationOnlySpec
         Database.Persist.TH.MultiBlockSpec
         Database.Persist.TH.MultiBlockSpec.Model
@@ -189,8 +191,7 @@
     build-depends:    base
                     , persistent
                     , criterion
-                    , deepseq
-                    , deepseq-generics
+                    , deepseq >= 1.4
                     , file-embed
                     , text
                     , template-haskell
diff --git a/test/Database/Persist/TH/KindEntitiesSpec.hs b/test/Database/Persist/TH/KindEntitiesSpec.hs
new file mode 100644
--- /dev/null
+++ b/test/Database/Persist/TH/KindEntitiesSpec.hs
@@ -0,0 +1,38 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE DerivingStrategies #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE GADTs #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE OverloadedLabels #-}
+{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE StandaloneDeriving #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE UndecidableInstances #-}
+
+module Database.Persist.TH.KindEntitiesSpec where
+
+import Database.Persist.TH.KindEntitiesSpecImports
+import TemplateTestImports
+
+mkPersist sqlSettings [persistLowerCase|
+
+Customer
+    name    String
+    age     Int
+
+CustomerTransfer
+    customerId CustomerId
+    moneyAmount (MoneyAmount 'CustomerOwned 'Debit)
+|]
+
+spec :: Spec
+spec = describe "KindEntities" $ do
+    it "should support DataKinds in entity definition" $ do
+        let mkTransfer :: CustomerId -> MoneyAmount 'CustomerOwned 'Debit -> CustomerTransfer
+            mkTransfer = CustomerTransfer
+            getAmount :: CustomerTransfer -> MoneyAmount 'CustomerOwned 'Debit
+            getAmount = customerTransferMoneyAmount
+        compiles
+
+compiles :: Expectation
+compiles = True `shouldBe` True
diff --git a/test/Database/Persist/TH/KindEntitiesSpecImports.hs b/test/Database/Persist/TH/KindEntitiesSpecImports.hs
new file mode 100644
--- /dev/null
+++ b/test/Database/Persist/TH/KindEntitiesSpecImports.hs
@@ -0,0 +1,22 @@
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE LambdaCase #-}
+
+module Database.Persist.TH.KindEntitiesSpecImports where
+
+import Data.Proxy
+import qualified Data.Text as T
+import TemplateTestImports
+
+data Owner = MerchantOwned | CustomerOwned
+data AccountKind = Debit | Credit
+
+newtype MoneyAmount (a :: Owner) (b :: AccountKind) = MoneyAmount Rational
+
+instance PersistFieldSql (MoneyAmount a b) where
+    sqlType _ = sqlType (Proxy :: Proxy Rational)
+
+instance PersistField (MoneyAmount a b) where
+    toPersistValue (MoneyAmount n) =
+        toPersistValue n
+    fromPersistValue v =
+        MoneyAmount <$> fromPersistValue v