diff --git a/changelog.md b/changelog.md
--- a/changelog.md
+++ b/changelog.md
@@ -1,19 +1,27 @@
-# 1.1.0.0 (2023-02-25)
+## 1.1.0.1 (2023-02-25)
 
+Various minor internal cleanup and simplification.
+
+Added dependency on the `quaalude` package.
+
+Haskell version is now GHC2021. Requires at least GHC 9.2.
+
+## 1.1.0.0 (2023-02-25)
+
 The `NoSuchName` constructor of `Error` now has an additional field that
 indicates which sockets are available.
 
 The `displayException` method of `Error` has been changed from the default
 implementation; it now constructs sentences.
 
-# 1.0.0.2 (2023-01-08)
+## 1.0.0.2 (2023-01-08)
 
 Support GHC 9.4
 
-# 1.0.0.1 (2021-12-27)
+## 1.0.0.1 (2021-12-27)
 
 Support GHC 9.2
 
-# 1 (2021-07-07)
+## 1 (2021-07-07)
 
 Initial release
diff --git a/src/SocketActivation.hs b/src/SocketActivation.hs
--- a/src/SocketActivation.hs
+++ b/src/SocketActivation.hs
@@ -5,8 +5,8 @@
     )
     where
 
-import Control.Applicative (Applicative ((*>)))
-import Control.Monad (Monad (return, (>>=)))
+import Essentials
+
 import Data.Either (Either, either)
 import System.IO (IO, print)
 
@@ -23,4 +23,4 @@
 getMySocketByName name = f SA.checkRecipient *> f (SA.getSocketByName name)
   where
     f :: IO (Either Error a) -> IO a
-    f = (>>= either (\e -> (SA.getEnvVars >>= print) *> Ex.throw e) return)
+    f = (>>= either (\e -> (SA.getEnvVars >>= print) *> Ex.throw e) pure)
diff --git a/src/SocketActivation/CheckRecipient.hs b/src/SocketActivation/CheckRecipient.hs
--- a/src/SocketActivation/CheckRecipient.hs
+++ b/src/SocketActivation/CheckRecipient.hs
@@ -2,13 +2,13 @@
 
 module SocketActivation.CheckRecipient where
 
-import Control.Monad (Monad (return, (>>=)))
+import Essentials
+
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Data.Either (Either)
-import Data.Eq (Eq ((==)))
-import Data.Function ((.))
 import System.IO (IO)
 
+import qualified Control.Monad as Monad
 import qualified System.Posix.Process as Sys
 
 import SocketActivation.Concepts (Error(WrongProcess), Recipient (recipientPID))
@@ -16,14 +16,11 @@
 import SocketActivation.IO (IO' (IO', run), throwError)
 
 checkRecipient :: IO (Either Error ())
-checkRecipient = run (getIt >>= checkIt)
-  where
-    getIt = IO' (getEnv' @Recipient)
-    checkIt = IO' . checkRecipient'
+checkRecipient = run do
+    recipient <- IO' $ getEnv' @Recipient
+    IO' $ checkRecipient' recipient
 
 checkRecipient' :: Recipient -> IO (Either Error ())
-checkRecipient' x = run (getMyPid >>= throwIfDifferent)
-  where
-    getMyPid = liftIO Sys.getProcessID
-    throwIfDifferent y =
-        if recipientPID x == y then return () else throwError WrongProcess
+checkRecipient' recipient = run do
+    myPid <- liftIO Sys.getProcessID
+    Monad.unless (recipientPID recipient == myPid) $ throwError WrongProcess
diff --git a/src/SocketActivation/Concepts.hs b/src/SocketActivation/Concepts.hs
--- a/src/SocketActivation/Concepts.hs
+++ b/src/SocketActivation/Concepts.hs
@@ -12,16 +12,15 @@
     )
     where
 
+import Essentials
+
 import Control.Exception (Exception (..), SomeException (..))
-import Data.Functor ((<$>))
-import Data.Function ((.))
-import Data.Semigroup ((<>))
-import Data.String (IsString)
+import Data.String (IsString, String)
 import Data.Text (Text)
 import Data.Typeable (cast)
 import Network.Socket (Socket)
 import Numeric.Natural (Natural)
-import Prelude (Bounded, Enum, Eq, Ord, Show, String, show)
+import Prelude (show)
 import System.Posix.Types (Fd (..), ProcessID)
 
 import qualified Data.Text as Text
diff --git a/src/SocketActivation/Env.hs b/src/SocketActivation/Env.hs
--- a/src/SocketActivation/Env.hs
+++ b/src/SocketActivation/Env.hs
@@ -1,12 +1,10 @@
 module SocketActivation.Env where
 
-import Control.Monad (Monad (return, (>>=)))
+import Essentials
+
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Data.Either (Either, either)
-import Data.Function (($), (.))
-import Data.Maybe (Maybe (..), maybe)
 import Data.Text (Text)
-import Data.Traversable (Traversable (traverse))
 import Prelude (Bounded (maxBound, minBound))
 import System.IO (IO)
 import Text.Show (show)
@@ -20,26 +18,21 @@
 import SocketActivation.Parsing (readRecipient, readCount, readNames)
 
 getVarText :: VarName -> IO (Either Error Text)
-getVarText name = run (getMaybe >>= throwIfMissing >>= pack)
+getVarText name = run $ getMaybe >>= throwIfMissing <&> Text.pack
   where
-    throwIfMissing = maybe (throwError (Missing name)) return
+    throwIfMissing = maybe (throwError (Missing name)) pure
     getMaybe = liftIO $ Sys.lookupEnv $ show @VarName name
-    pack = return . Text.pack
 
 getEnvVars :: IO [(VarName, Maybe Text)]
-getEnvVars =
-    traverse
-        (\x -> getVarText x >>= \y ->
-            return (x, either (\_ -> Nothing) Just y))
-        [minBound .. maxBound]
+getEnvVars = [minBound .. maxBound] & traverse \x ->
+    getVarText x <&> \y -> (x, either (\_ -> Nothing) Just y)
 
 data Env a = Env VarName (Text -> Maybe a)
 
 getEnv :: Env a -> IO (Either Error a)
-getEnv (Env name read) = run (getText >>= readOrThrow)
-  where
-    getText = IO' (getVarText name)
-    readOrThrow = maybe (throwError (Invalid name)) return . read
+getEnv (Env name read) = run $
+    IO' (getVarText name) >>=
+    (maybe (throwError (Invalid name)) pure . read)
 
 getEnv' :: Env' a => IO (Either Error a)
 getEnv' = getEnv env'
diff --git a/src/SocketActivation/GetByName.hs b/src/SocketActivation/GetByName.hs
--- a/src/SocketActivation/GetByName.hs
+++ b/src/SocketActivation/GetByName.hs
@@ -1,13 +1,11 @@
 module SocketActivation.GetByName where
 
-import Control.Applicative (Applicative ((<*>)), (<$>))
-import Control.Monad (Monad (return, (>>=)))
+import Essentials
+
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Data.Either (Either)
-import Data.Function ((.))
 import Data.List (zip)
 import Data.Map (Map)
-import Data.Maybe (maybe)
 import System.IO (IO)
 
 import qualified Data.Map as Map
@@ -20,30 +18,22 @@
 import SocketActivation.IO (IO' (IO', run), throwError)
 
 getNameList :: IO (Either Error [Name])
-getNameList = run (getNames >>= unwrap)
-  where
-    getNames = IO' (getEnv' @Names)
-    unwrap = return . namesList
+getNameList = run $ IO' (getEnv' @Names) <&> namesList
 
 getFileDescriptorMap :: IO (Either Error (Map Name Fd))
-getFileDescriptorMap = run (entries >>= toMap)
+getFileDescriptorMap = run $ entries <&> Map.fromList
   where
-    entries = zip <$> keys <*> values
-    keys = IO' getNameList
-    values = IO' getFileDescriptorList
-    toMap = return . Map.fromList
+    entries = zip <$> IO' getNameList <*> IO' getFileDescriptorList
 
 getSocketMap :: IO (Either Error (Map Name Socket))
-getSocketMap = run (entries >>= toMap)
+getSocketMap = run (entries <&> Map.fromList)
   where
-    entries = zip <$> keys <*> values
-    keys = IO' getNameList
-    values = IO' getSocketList
-    toMap = return . Map.fromList
+    entries = zip <$> IO' getNameList <*> IO' getSocketList
 
 getSocketByName :: Name -> IO (Either Error Socket)
-getSocketByName name = run (getMap >>= findFd >>= convertToSocket)
-  where
-    getMap = IO' getFileDescriptorMap
-    findFd m = maybe (throwError (NoSuchName name (Map.keys m))) return (Map.lookup name m)
-    convertToSocket = liftIO . fdSocket
+getSocketByName name = run do
+    m <- IO' getFileDescriptorMap
+    fd <- case Map.lookup name m of
+        Nothing -> throwError (NoSuchName name (Map.keys m))
+        Just x -> pure x
+    liftIO $ fdSocket fd
diff --git a/src/SocketActivation/GetFileDescriptors.hs b/src/SocketActivation/GetFileDescriptors.hs
--- a/src/SocketActivation/GetFileDescriptors.hs
+++ b/src/SocketActivation/GetFileDescriptors.hs
@@ -1,11 +1,9 @@
 module SocketActivation.GetFileDescriptors where
 
-import Control.Monad (Monad (return, (>>=)))
+import Essentials
+
 import Data.Either (Either)
-import Data.Function ((.))
-import Data.Int (Int)
 import Data.List (take)
-import Numeric.Natural (Natural)
 import Prelude (fromIntegral)
 import System.IO (IO)
 
@@ -15,13 +13,7 @@
 
 {-| Get a list of file descriptors for the sockets -}
 getFileDescriptorList :: IO (Either Error [Fd])
-getFileDescriptorList = run (getCount >>= enumerateFds)
-  where
-    getCount = IO' (getEnv' @Count)
-    enumerateFds = return . fds
+getFileDescriptorList = run $ IO' (getEnv' @Count) <&> fds
 
 fds :: Count -> [Fd]
-fds n = take (convert n) [firstFd ..]
-  where
-    convert = (fromIntegral :: Natural -> Int) . countNat
-    firstFd = Fd 3
+fds n = take (fromIntegral (countNat n)) [Fd 3 ..]
diff --git a/src/SocketActivation/GetSockets.hs b/src/SocketActivation/GetSockets.hs
--- a/src/SocketActivation/GetSockets.hs
+++ b/src/SocketActivation/GetSockets.hs
@@ -1,10 +1,9 @@
 module SocketActivation.GetSockets where
 
-import Control.Monad (Monad ((>>=)))
+import Essentials
+
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Data.Either (Either)
-import Data.Function ((.))
-import Data.Traversable (Traversable (traverse))
 import System.IO (IO)
 
 import qualified Network.Socket as Net
@@ -14,10 +13,8 @@
 import SocketActivation.IO (IO' (IO', run))
 
 getSocketList :: IO (Either Error [Socket])
-getSocketList = run (getFds >>= convertToSockets)
-  where
-    getFds = IO' getFileDescriptorList
-    convertToSockets = traverse (liftIO . fdSocket)
+getSocketList = run $
+    IO' getFileDescriptorList >>= traverse (liftIO . fdSocket)
 
 fdSocket :: Fd -> IO Socket
 fdSocket (Fd i) = Net.mkSocket i
diff --git a/src/SocketActivation/IO.hs b/src/SocketActivation/IO.hs
--- a/src/SocketActivation/IO.hs
+++ b/src/SocketActivation/IO.hs
@@ -1,11 +1,10 @@
 module SocketActivation.IO where
 
-import Control.Applicative (Applicative)
-import Control.Monad (Functor, Monad (return))
+import Essentials
+
 import Control.Monad.IO.Class (MonadIO)
 import Control.Monad.Trans.Except (ExceptT (..))
 import Data.Either (Either (Left))
-import Data.Function ((.))
 import System.IO (IO)
 
 import SocketActivation.Concepts (Error)
@@ -14,4 +13,4 @@
     deriving (Functor, Applicative, Monad, MonadIO) via ExceptT Error IO
 
 throwError :: Error -> IO' a
-throwError = IO' . return . Left
+throwError = IO' . pure . Left
diff --git a/src/SocketActivation/Parsing.hs b/src/SocketActivation/Parsing.hs
--- a/src/SocketActivation/Parsing.hs
+++ b/src/SocketActivation/Parsing.hs
@@ -1,9 +1,8 @@
 module SocketActivation.Parsing where
 
-import Control.Monad (Functor (fmap), Monad (return), (>=>))
+import Essentials
+
 import Data.Bits (toIntegralSized)
-import Data.Function ((.))
-import Data.Maybe (Maybe)
 import Data.Text (Text)
 import Foreign.C.Types (CInt)
 import Numeric.Natural (Natural)
@@ -17,14 +16,14 @@
 readRecipient = read >=> wrap
   where
     read = readMaybe @ProcessID . Text.unpack
-    wrap = return . RecipientPID
+    wrap = pure . RecipientPID
 
 readCount :: Text -> Maybe Count
 readCount = read >=> convert >=> wrap
   where
     read = readMaybe @CInt . Text.unpack
     convert = toIntegralSized :: CInt -> Maybe Natural
-    wrap = return . CountNat
+    wrap = pure . CountNat
 
 readNames :: Text -> Names
 readNames = NamesList . fmap NameText . Text.splitOn ":"
diff --git a/systemd-socket-activation.cabal b/systemd-socket-activation.cabal
--- a/systemd-socket-activation.cabal
+++ b/systemd-socket-activation.cabal
@@ -1,7 +1,7 @@
 cabal-version: 3.0
 
 name: systemd-socket-activation
-version: 1.1.0.0
+version: 1.1.0.1
 category: System, Network
 synopsis: Let systemd bind the server's socket for you
 
@@ -28,14 +28,12 @@
     location: https://github.com/typeclasses/systemd-socket-activation
 
 library
-    default-language: Haskell2010
+    default-language: GHC2021
     ghc-options: -Wall
     hs-source-dirs: src
 
-    default-extensions: DeriveAnyClass DerivingStrategies
-        DerivingVia LambdaCase GeneralizedNewtypeDeriving
+    default-extensions: BlockArguments DerivingVia LambdaCase
         NoImplicitPrelude OverloadedStrings
-        ScopedTypeVariables TypeApplications
 
     exposed-modules:
         SocketActivation
@@ -51,8 +49,9 @@
         SocketActivation.Parsing
 
     build-depends:
-      , base         ^>= 4.14 || ^>= 4.15 || ^>= 4.16 || ^>= 4.17
+      , base         ^>= 4.16 || ^>= 4.17
       , containers   ^>= 0.6.4
+      , quaalude     ^>= 0.0.0
       , network      ^>= 3.1.2
       , text         ^>= 1.2.4 || ^>= 2.0
       , transformers ^>= 0.5.6 || ^>= 0.6