Hello, I am very pleased to announce the release of iteratee-0.4.0.1. This release features several breaking changes from prior versions, including a new low-level implementation. Type names have been changed to bring them closer in line to Oleg's publications, the iteratee type has been simplified and requires fewer type variables, WrappedByteString is no longer necessary or provided, and many of the special combinators such as ($$) are no longer required. Another very powerful feature is a user-extensible mechanism for iteratees to alter enumerator behavior, enabled by the new exception mechanism and the callback-based enumerator interface. A simple example of this feature is the provided "seek" implementation. Other improvements include re-written documentation and new example files in the Examples folder (available after unpacking the hackage distribution). There is also a new tutorial in the Examples folder provided by Ben Lee, which details the new CPS-based implementation. If you've tried iteratee before but had trouble understanding it, please consider having another look. I have also released the package "iteratee-mtl", which is identical to the main package except it is based upon mtl. Due to the type name changes, iteratee-0.4 is incompatible with prior releases. Updating code to this release can be as simple as changing types/imports, although in many cases the conversion will be more involved. For those users who are unable to update to this release, I am also pleased to announce Iteratee-0.3.6, the final release of the 0.3.x line. It has been somewhat cleaned up and features several powerful new functions contributed by Conrad Parker and Brian Lewis, including "ioIter", "mapM_", and "enumFdFollow". These functions will be migrated to the 0.4 line in due course. I am most grateful to many people who contributed to this release. Thanks especially to Conrad Parker, Antoine Latter, Ben Lee, Paulo Tanimoto, and Edward Yang for many significant improvements. Thank you, John Lato