diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Changelog for unliftio
 
+## 0.2.25.1
+
+* Forward compatibility with `-Wnoncanonical-monoid-instances` becoming an error
+
 ## 0.2.25.0
 
 * Add `UnliftIO.Exception.Lens`
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -7,12 +7,6 @@
 instances, and a collection of common functions working with it.  Not
 sure what the `MonadUnliftIO` typeclass is all about? Read on!
 
-__NOTE__ This library is young, and will likely undergo some serious changes
-over time. It's also very lightly tested. That said: the core concept of
-`MonadUnliftIO` has been refined for years and is pretty solid, and even though
-the code here is lightly tested, the vast majority of it is simply apply
-`withUnliftIO` to existing functionality. Caveat emptor and all that.
-
 __NOTE__ The `UnliftIO.Exception` module in this library changes the semantics of asynchronous exceptions to be in the style of the `safe-exceptions` package, which is orthogonal to the "unlifting" concept. While this change is an improvment in most cases, it means that `UnliftIO.Exception` is not always a drop-in replacement for `Control.Exception` in advanced exception handling code. See [Async exception safety](#async-exception-safety) for details.
 
 ## Quickstart
@@ -26,7 +20,7 @@
 * Drop the deps on `monad-control`, `lifted-base`, and `exceptions`
 * Compilation failures? You may have just avoided subtle runtime bugs
 
-Sound like magic? It's not. Keep reading!
+Sounds like magic? It's not. Keep reading!
 
 ## Unlifting in 2 minutes
 
@@ -366,7 +360,7 @@
 The `unliftio-core` package provides just the typeclass with minimal
 dependencies (just `base` and `transformers`). If you're writing a
 library, we recommend depending on that package to provide your
-instances. The `unliftio` package is a "batteries loaded" library
+instances. The `unliftio` package is a "batteries included" library
 providing a plethora of pre-unlifted helper functions. It's a good
 choice for importing, or even for use in a custom prelude.
 
@@ -379,7 +373,7 @@
 remove the dependency on them here.
 
 If there are other temporary orphans that should be added, please
-bring it up in the issue tracker or send a PR, but we'll need to be
+bring them up in the issue tracker or send a PR, but we'll need to be
 selective about adding dependencies.
 
 ## Future questions
diff --git a/src/UnliftIO/Internals/Async.hs b/src/UnliftIO/Internals/Async.hs
--- a/src/UnliftIO/Internals/Async.hs
+++ b/src/UnliftIO/Internals/Async.hs
@@ -510,8 +510,10 @@
 instance (Monoid a, MonadUnliftIO m) => Monoid (Conc m a) where
   mempty = pure mempty
   {-# INLINE mempty #-}
+#if !MIN_VERSION_base(4,11,0)
   mappend = liftA2 mappend
   {-# INLINE mappend #-}
+#endif
 
 -------------------------
 -- Conc implementation --
diff --git a/unliftio.cabal b/unliftio.cabal
--- a/unliftio.cabal
+++ b/unliftio.cabal
@@ -1,11 +1,11 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.35.1.
+-- This file has been generated from package.yaml by hpack version 0.37.0.
 --
 -- see: https://github.com/sol/hpack
 
 name:           unliftio
-version:        0.2.25.0
+version:        0.2.25.1
 synopsis:       The MonadUnliftIO typeclass for unlifting monads to IO (batteries included)
 description:    Please see the documentation and README at <https://www.stackage.org/package/unliftio>
 category:       Control