diff --git a/src/Quasar/Async.hs b/src/Quasar/Async.hs
index ebffedf6b8d701378735a0eef9524cb4ef9472be..3a51b99182e08d598dfab7ce3c6abf3ffab11a9f 100644
--- a/src/Quasar/Async.hs
+++ b/src/Quasar/Async.hs
@@ -1,5 +1,5 @@
 module Quasar.Async (
-  Async,
+  Async(..),
   async,
   async_,
   asyncWithUnmask,
@@ -15,11 +15,16 @@ module Quasar.Async (
   -- ** IO variant
   async',
   asyncWithUnmask',
+
+  -- ** Unmanaged variants
+  unmanagedAsync,
+  unmanagedAsyncWithUnmask,
 ) where
 
 import Control.Concurrent (ThreadId)
 import Control.Monad.Catch
 import Quasar.Async.Fork
+import Quasar.Async.STMHelper
 import Quasar.Future
 import Quasar.Exceptions
 import Quasar.MonadQuasar
@@ -63,17 +68,31 @@ async' fn = asyncWithUnmask' ($ fn)
 
 asyncWithUnmask' :: forall a m. (MonadQuasar m, MonadIO m) => ((forall b. IO b -> IO b) -> IO a) -> m (Async a)
 asyncWithUnmask' fn = liftQuasarIO do
-  exChan <- askExceptionSink
+  worker <- askIOWorker
+  exSink <- askExceptionSink
+  spawnAsync registerResourceIO worker exSink fn
+
+
+unmanagedAsync :: forall a m. MonadIO m => TIOWorker -> ExceptionSink -> IO a -> m (Async a)
+unmanagedAsync worker exSink fn = liftIO $ unmanagedAsyncWithUnmask worker exSink ($ fn)
 
+unmanagedAsyncWithUnmask :: forall a m. MonadIO m => TIOWorker -> ExceptionSink -> ((forall b. IO b -> IO b) -> IO a) -> m (Async a)
+unmanagedAsyncWithUnmask worker exSink fn = liftIO $ spawnAsync (\_ -> pure ()) worker exSink fn
+
+
+spawnAsync :: forall a m. (MonadIO m, MonadMask m) => (Disposer -> m ()) -> TIOWorker -> ExceptionSink -> ((forall b. IO b -> IO b) -> IO a) -> m (Async a)
+spawnAsync registerDisposerFn worker exSink fn = do
   key <- liftIO newUnique
   resultVar <- newPromise
 
   afixExtra \threadIdFuture -> mask_ do
 
     -- Disposer is created first to ensure the resource can be safely attached
-    disposer <- registerDisposeActionIO (disposeFn key resultVar threadIdFuture)
+    disposer <- atomically $ newUnmanagedIODisposer (disposeFn key resultVar threadIdFuture) worker exSink
+
+    registerDisposerFn disposer
 
-    threadId <- liftIO $ forkWithUnmask (runAndPut exChan key resultVar disposer) exChan
+    threadId <- liftIO $ forkWithUnmask (runAndPut exSink key resultVar disposer) exSink
 
     pure (Async (toFuture resultVar) disposer, threadId)
   where
@@ -94,7 +113,7 @@ asyncWithUnmask' fn = liftQuasarIO do
           disposeEventuallyIO_ disposer
     disposeFn :: Unique -> Promise a -> Future ThreadId -> IO ()
     disposeFn key resultVar threadIdFuture = do
-      -- Should not block or fail (unless the TIOWorker is broken)
+      -- ThreadId future will be filled by afix
       threadId <- await threadIdFuture
       throwTo threadId (CancelAsync key)
       -- Disposing is considered complete once a result (i.e. success or failure) has been stored