diff --git a/ChangeLog.md b/ChangeLog.md
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+++ b/ChangeLog.md
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+# Changelog for thread-finalizers
+
+## Unreleased changes
diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+Copyright Ian Duncan (c) 2021
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Ian Duncan nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/README.md b/README.md
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--- /dev/null
+++ b/README.md
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+# thread-finalizers
diff --git a/Setup.hs b/Setup.hs
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--- /dev/null
+++ b/Setup.hs
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+import Distribution.Simple
+main = defaultMain
diff --git a/src/Control/Concurrent/Thread/Finalizers.hs b/src/Control/Concurrent/Thread/Finalizers.hs
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+++ b/src/Control/Concurrent/Thread/Finalizers.hs
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+{-# LANGUAGE MagicHash #-}
+{-# LANGUAGE UnboxedTuples #-}
+module Control.Concurrent.Thread.Finalizers where
+import Control.Concurrent
+import Control.Exception
+import Control.Monad ( void )
+import GHC.IO (IO(..))
+import GHC.Prim ( mkWeak# )
+import GHC.Weak ( Weak(..) )
+import GHC.Conc.Sync ( ThreadId(..) )
+
+-- | A variant of 'Control.Concurrent.mkWeakThreadId' that supports
+-- finalization.
+--
+-- Make a weak pointer to a 'ThreadId'.  It can be important to do
+-- this if you want to hold a reference to a 'ThreadId' while still
+-- allowing the thread to receive the @BlockedIndefinitely@ family of
+-- exceptions (e.g. 'BlockedIndefinitelyOnMVar').  Holding a normal
+-- 'ThreadId' reference will prevent the delivery of
+-- @BlockedIndefinitely@ exceptions because the reference could be
+-- used as the target of 'throwTo' at any time, which would unblock
+-- the thread.
+--
+-- Holding a @Weak ThreadId@, on the other hand, will not prevent the
+-- thread from receiving @BlockedIndefinitely@ exceptions.  It is
+-- still possible to throw an exception to a @Weak ThreadId@, but the
+-- caller must use @deRefWeak@ first to determine whether the thread
+-- still exists.
+--
+mkWeakThreadIdWithFinalizer :: ThreadId -> IO () -> IO (Weak ThreadId)
+mkWeakThreadIdWithFinalizer t@(ThreadId t#) (IO finalizer) = IO $ \s ->
+  case mkWeak# t# t finalizer s of
+    (# s1, w #) -> (# s1, Weak w #)
+
+{-|
+  A specialised version of 'mkWeakThreadIdWithFinalizer', where the 'Weak' object
+  returned is simply thrown away (however the finalizer will be
+  remembered by the garbage collector, and will still be run
+  when the key becomes unreachable).
+-}
+addThreadFinalizer :: ThreadId -> IO () -> IO ()
+addThreadFinalizer tid m = void $ mkWeakThreadIdWithFinalizer tid m
diff --git a/test/Spec.hs b/test/Spec.hs
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--- /dev/null
+++ b/test/Spec.hs
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+main :: IO ()
+main = putStrLn "Test suite not yet implemented"
diff --git a/thread-utils-finalizers.cabal b/thread-utils-finalizers.cabal
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--- /dev/null
+++ b/thread-utils-finalizers.cabal
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+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.34.4.
+--
+-- see: https://github.com/sol/hpack
+
+name:           thread-utils-finalizers
+version:        0.1.0.0
+synopsis:       Perform finalization for threads.
+description:    Please see the README on GitHub at <https://github.com/iand675/thread-finalizers#readme>
+category:       Concurrency
+homepage:       https://github.com/iand675/thread-utils#readme
+bug-reports:    https://github.com/iand675/thread-utils/issues
+author:         Ian Duncan
+maintainer:     ian@iankduncan.com
+copyright:      2021 Ian Duncan
+license:        BSD3
+license-file:   LICENSE
+build-type:     Simple
+extra-source-files:
+    README.md
+    ChangeLog.md
+
+source-repository head
+  type: git
+  location: https://github.com/iand675/thread-utils
+
+library
+  exposed-modules:
+      Control.Concurrent.Thread.Finalizers
+  other-modules:
+      Paths_thread_utils_finalizers
+  hs-source-dirs:
+      src
+  build-depends:
+      base >=4.7 && <5
+    , ghc-prim
+  default-language: Haskell2010
+
+test-suite thread-finalizers-test
+  type: exitcode-stdio-1.0
+  main-is: Spec.hs
+  other-modules:
+      Paths_thread_utils_finalizers
+  hs-source-dirs:
+      test
+  ghc-options: -threaded -rtsopts -with-rtsopts=-N
+  build-depends:
+      base >=4.7 && <5
+    , ghc-prim
+    , thread-utils-finalizers
+  default-language: Haskell2010