Hello everyone, We (the platform release team) have a policy question about the Haskell Platform. We're asking here because we think the libraries list is the right authority to decide. The Haskell Platform concept calls for major and minor releases. * The point of major releases is to update the set of common packages we all use. That is, to specify which packages and which versions (corresponding to APIs). The target is to have major releases every 6 months. * The point of minor releases is to support a major release across a range of operating systems over time and respond to bugs that are discovered in a library or tool subsequent to their release. The target is to have 2-3 minor releases after major releases at intervals on the order of 4-6 weeks. The question is this: Should we allow compatible API additions to a library in a minor release of the platform? The choice is between allowing only bug fixes in minor releases, or also allowing new features that add APIs but do not change any existing APIs. It is clear that incompatible API changes must not be allowed in minor releases. On the other hand, bug fixes that do not change the API at all are ok. Let me put some arguments in each case: Allow compatible API additions If the change is compatible then it does not break any existing programs, so it should be allowed. Any program that works with a platform particular release will continue to work with subsequent minor versions. This is standard backwards compatibility policy. Getting minor feature improvements is sufficiently important that it is too long to wait 6 months for the next major release of the platform. Allow only bug fixes, no API additions Forwards compatibility is important too. A developer should be able to make a package and test it with platform version X.Y.2 and it should still work for a user with version X.Y.1. That way we do not force upgrades on users all the time. Users should only have to upgrade to a later minor release if earlier versions didn't build/install/work on their OS, or if they hit some particular bug which is fixed in a later minor release. There is no need for API changes in minor releases. Maintainers can make a release with just the bug fixes to go into a minor platform release and then make additional releases with new features on Hackage. Users who want the new features can get the new package version from Hackage. API additions in minor releases works against the distinction between major and minor releases. I hope that's not too biased a summary (I'll post my own opinion separately). If there is anything that I should clarify then please ask. So please post your thoughts and arguments. I hope we can come to a conclusion within a few days. This is a timely issue because we aim to make a minor release on the 1st of June and we want to finalise the list of package versions two weeks prior, by the 18th of May. http://trac.haskell.org/haskell-platform/wiki/ReleaseProcess Duncan