This library provides an STM monad with commit and retry IO hooks. A retry-action is run (once) in a separate thread if the transaction retries, while commit-actions are executed iff the transaction commits. The code is based on the AdvSTM Monad [1] by Chris Kuklewicz, but in addition also ensures some atomicity guarantees for commit-actions, see documentation for details. Cheers, Peter [1] http://www.haskell.org/haskellwiki/New_monads/MonadAdvSTM