diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # ChangeLog for unliftio-core
 
+## 0.2.0.1
+
+* Remove faulty default implementation of `withRunInIO` [#56](https://github.com/fpco/unliftio/issues/56)
+
 ## 0.2.0.0
 
 * Move `askUnliftIO` out of class [#55](https://github.com/fpco/unliftio/issues/55)
diff --git a/src/Control/Monad/IO/Unlift.hs b/src/Control/Monad/IO/Unlift.hs
--- a/src/Control/Monad/IO/Unlift.hs
+++ b/src/Control/Monad/IO/Unlift.hs
@@ -57,9 +57,7 @@
   -- action @m@ in @IO@.
   --
   -- @since 0.1.0.0
-  {-# INLINE withRunInIO #-}
   withRunInIO :: ((forall a. m a -> IO a) -> IO b) -> m b
-  withRunInIO inner = askUnliftIO >>= \u -> liftIO (inner (unliftIO u))
 instance MonadUnliftIO IO where
   {-# INLINE withRunInIO #-}
   withRunInIO inner = inner id
diff --git a/unliftio-core.cabal b/unliftio-core.cabal
--- a/unliftio-core.cabal
+++ b/unliftio-core.cabal
@@ -4,17 +4,17 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 9b9f7a8193dd633099cfaf8dc393fdfd8a2a5ea77517a9ad27a80ef76c429ff0
+-- hash: 9cae5ca1af8760786d8e586fd9b1ed7e329f13f4ec8a3d0aee62818b25038c1f
 
 name:           unliftio-core
-version:        0.2.0.0
+version:        0.2.0.1
 synopsis:       The MonadUnliftIO typeclass for unlifting monads to IO
 description:    Please see the documentation and README at <https://www.stackage.org/package/unliftio-core>
 category:       Control
 homepage:       https://github.com/fpco/unliftio/tree/master/unliftio-core#readme
 author:         Michael Snoyman, Francesco Mazzoli
 maintainer:     michael@snoyman.com
-copyright:      2017 FP Complete
+copyright:      2017-2020 FP Complete
 license:        MIT
 license-file:   LICENSE
 build-type:     Simple