diff --git a/diagrams-core.cabal b/diagrams-core.cabal
index 0701a35..a08f2b5 100644
--- a/diagrams-core.cabal
+++ b/diagrams-core.cabal
@@ -15,7 +15,7 @@ Build-type:          Simple
 Cabal-version:       1.18
 Extra-source-files:  diagrams/*.svg
 extra-doc-files:     diagrams/*.svg, CHANGELOG.md, README.markdown
-Tested-with:         GHC ==8.4.4 || ==8.6.5 || ==8.8.4 || ==8.10.7 || ==9.0.2 || ==9.2.8 || ==9.4.5 || ==9.6.2
+Tested-with:         GHC ==8.4.4 || ==8.6.5 || ==8.8.4 || ==8.10.7 || ==9.0.2 || ==9.2.8 || ==9.4.7 || ==9.6.3 || ==9.8.1
 Source-repository head
   type:     git
   location: git://github.com/diagrams/diagrams-core.git
@@ -36,7 +36,7 @@ Library
                        Diagrams.Core.Types,
                        Diagrams.Core.V
 
-  Build-depends:       base >= 4.11 && < 4.19,
+  Build-depends:       base >= 4.11 && < 4.20,
                        containers >= 0.4.2 && < 0.7,
                        unordered-containers >= 0.2 && < 0.3,
                        semigroups >= 0.8.4 && < 0.21,
diff --git a/src/Diagrams/Core/Measure.hs b/src/Diagrams/Core/Measure.hs
index c685ab5..5299f6f 100644
--- a/src/Diagrams/Core/Measure.hs
+++ b/src/Diagrams/Core/Measure.hs
@@ -126,7 +126,6 @@ instance Semigroup a => Semigroup (Measured n a) where
 
 instance Monoid a => Monoid (Measured n a) where
   mempty  = pure mempty
-  mappend = liftA2 mappend
 
 instance Distributive (Measured n) where
   distribute a = Measured $ \x -> fmap (\(Measured m) -> m x) a