Re: Periodical releases

[Carsten Mattner <carstenmattner@googlemail.com>]

On Sun, Jan 1, 2012 at 11:41 PM, Stefan Monnier
<monnier@iro.umontreal.ca> wrote:
>> Maybe 2 or 4 releases as a minimum per year with less major
>> changes in each?
>
> For Emacs-21, the main time constraint was to get the new redisplay
> engine stable (with support for proportional fonts and such).
> Can't remember any such large change for Emacs-22, off hand.
> But for Emacs-23, there was a similar issue with the change to a utf-8
> based internal representation and the new font handling.
> For Emacs-24, it was the bidi support mostly.
>
> These are fairly significant structural changes which are difficult to
> perform piecemeal and tend to introduce significant breakage which takes
> months if not years to test&debug (maybe partly for lack of a good
> regression test suite, but also because of very complex semantics, most
> of which is the result of accidental interferences between
> "independent" features).

The solution for that is to let it evolve in a branch for longer than
one release cycle while merging finished changes to the release
branch and deliver those features sooner.
That way finished features like say package support, built-in colour
theme support, cc-mode and other mode updates, etc., which are less
invasive, are delivered in a stable release faster.