You have already installed a development build of (what will become) Emacs 25. (Emacs 25 has not yet been released.)
So use C-h N to read the NEWS. It is specifically an outline description of all that will be new in Emacs 25.
There is little sense in people repeating that information here. Of course, particular people might want to draw attention to ...
Being an official GNU project it adheres closely to the GNU coding standards and directory layout. That said, if you are exploring the source tree I would start, as with most projects, with the README file in the root directory.
From that file onwards, there are several sub-directories:
`src' holds the C code for Emacs (the Emacs Lisp interpreter and
The NEWS file for Emacs 25 is available at http://git.savannah.gnu.org/cgit/emacs.git/tree/etc/NEWS?h=emacs-25 - it currently has about 400 items.
Since it's closer to release now, here is a (subjective) list of some of the major features included so far - items are subject to change. There are other features that might make it in also (x-widgets? someone ...
While I second other's comments here about places to go for interaction and coordination, there is another unique aspect to Emacs development. For its size, innovation, and coordination, it is a relatively quiet endeavor. Not much noise about itself. Major releases trigger a few dozen extra emails. Even for lengthy threads, the retorts are terse.
No, you are not missing anything, except the Emacs bugs mailing list: firstname.lastname@example.org (which uses debbugs.gnu.org).
And there is a git repository for the Emacs source code -- that is what is used.
Discussion is on email@example.com and firstname.lastname@example.org. Some code is exposed and discussed there.
But code development takes place by individuals ...
From a cursory look all regex matching functions end up using compile_pattern which first checks the built-in regex cache for a previously compiled one, compiling one when needed. The cache is a linked list with a hardcoded size of 20 items. New matches are put in the front of the list, essentially creating a LRU mechanism. See search.c for the details.
Answering myself :) There is a new page (which I just set up today) on EmacsWiki called Research About Emacs, and also a Zotero group called Emacs for all your reference convenience.
The former1 is, hopefully and potentially a growing, maintainable, close-to-Emacs-community and also search engine friendly page for documenting, disseminating, organizing and ...
Great question. I never noticed those buttons on the web page before.
Yes, if you click that button it will open your mail client with only the person you're replying to in the To list.
To have the mail also go to the bug list (for that bug thread) you need to also include the bug number in the To list (or the Cc list, I think), in this form: 12345@debbugs....
Every bug has a webpage, so if there is no other way then you can use a change notification service which sends you a mail when the page changes.
Or if you know elisp then you could even write a simple emacs script which runs a timer in the background fetching the page reglularly and notifies you if the content changes.
As @JordonBiondo reported here (this answer is a verbatim copy of his answer):
The procedure for reporting bugs, requesting features, and submitting pathces is outlined in the manual.
Or read online:
In a nutshell:
use report-emacs-bug for bug reporting and feature ...