diff --git a/hw-mquery.cabal b/hw-mquery.cabal
--- a/hw-mquery.cabal
+++ b/hw-mquery.cabal
@@ -1,7 +1,7 @@
 cabal-version:  2.2
 
 name:                   hw-mquery
-version:                0.2.1.0
+version:                0.2.1.1
 synopsis:               Monadic query DSL
 description:            Please see README.md
 category:               Data
@@ -9,10 +9,10 @@
 bug-reports:            https://github.com/haskell-works/hw-mquery/issues
 author:                 John Ky
 maintainer:             newhoggy@gmail.com
-copyright:              2018-2020 John Ky
+copyright:              2018-2021 John Ky
 license:                BSD-3-Clause
 license-file:           LICENSE
-tested-with:            GHC == 8.10.1, GHC == 8.8.3, GHC == 8.6.5, GHC == 8.4.4
+tested-with:            GHC == 9.2.2, GHC == 9.0.2, GHC == 8.10.7, GHC == 8.8.4, GHC == 8.6.5
 build-type:             Simple
 extra-source-files:     README.md
 
@@ -23,16 +23,16 @@
 common base                       { build-depends: base                       >= 4.11       && < 5      }
 
 common ansi-wl-pprint             { build-depends: ansi-wl-pprint             >= 0.6.8      && < 0.7    }
-common dlist                      { build-depends: dlist                      >= 0.8.0      && < 0.9    }
-common doctest                    { build-depends: doctest                    >= 0.16.2     && < 0.17   }
+common dlist                      { build-depends: dlist                      >= 0.8.0      && < 1.1    }
+common doctest                    { build-depends: doctest                    >= 0.16.2     && < 0.21   }
 common doctest-discover           { build-depends: doctest-discover           >= 0.2        && < 0.3    }
-common hedgehog                   { build-depends: hedgehog                   >= 0.6.1      && < 1.1    }
-common hspec                      { build-depends: hspec                      >= 2.6.0      && < 2.8.0  }
+common hedgehog                   { build-depends: hedgehog                   >= 0.6.1      && < 1.2    }
+common hspec                      { build-depends: hspec                      >= 2.6.0      && < 3      }
 common hw-hspec-hedgehog          { build-depends: hw-hspec-hedgehog          >= 0.1.0.5    && < 0.2    }
-common lens                       { build-depends: lens                       >= 4.17       && < 5      }
+common lens                       { build-depends: lens                       >= 4.17       && < 6      }
 
 common config
-  ghc-options:          -Wall -msse4.2
+  ghc-options:          -Wall
   default-language:     Haskell2010
 
 common hw-mquery
@@ -87,7 +87,7 @@
                       , hw-mquery
   default-language:     Haskell2010
   type:                 exitcode-stdio-1.0
-  ghc-options:          -threaded
+  ghc-options:          -threaded -rtsopts -with-rtsopts=-N
   main-is:              DoctestDriver.hs
   HS-Source-Dirs:       doctest
   build-tool-depends:   doctest-discover:doctest-discover
diff --git a/src/HaskellWorks/Data/MQuery.hs b/src/HaskellWorks/Data/MQuery.hs
--- a/src/HaskellWorks/Data/MQuery.hs
+++ b/src/HaskellWorks/Data/MQuery.hs
@@ -104,7 +104,6 @@
 
 instance Monoid (MQuery a) where
   mempty = MQuery DL.empty
-  mappend (MQuery a) (MQuery b) = MQuery (a `DL.append` b)
 
 (/^.) :: Monad m => s -> Getting a s a -> m a
 (/^.) a g = return (a ^. g)
diff --git a/test/HaskellWorks/Data/MQuerySpec.hs b/test/HaskellWorks/Data/MQuerySpec.hs
--- a/test/HaskellWorks/Data/MQuerySpec.hs
+++ b/test/HaskellWorks/Data/MQuerySpec.hs
@@ -11,9 +11,9 @@
 import qualified Data.Foldable                as F
 import qualified HaskellWorks.Data.Model.Lens as L
 
-{-# ANN module ("HLint: ignore Redundant do"        :: String) #-}
-{-# ANN module ("HLint: ignore Reduce duplication"  :: String) #-}
-{-# ANN module ("HLint: ignore Redundant bracket"          :: String) #-}
+{- HLINT ignore "Redundant do"        -}
+{- HLINT ignore "Reduce duplication"  -}
+{- HLINT ignore "Redundant bracket"   -}
 
 spec :: Spec
 spec = describe "HaskellWorks.Data.MQuerySpec" $ do