From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pjotr Prins Subject: Re: Having a Guix archive on the download page? Date: Wed, 11 Jul 2018 18:13:51 +0200 Message-ID: <20180711161351.zyers5wm373vlcpm@thebird.nl> References: <20180707121712.7mduwpoesyyeucqj@thebird.nl> <874lh6kk32.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:38216) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fdHkb-0001u6-1Y for guix-devel@gnu.org; Wed, 11 Jul 2018 12:13:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fdHkX-0005NW-TH for guix-devel@gnu.org; Wed, 11 Jul 2018 12:13:57 -0400 Content-Disposition: inline In-Reply-To: <874lh6kk32.fsf@gnu.org> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: "Guix-devel" To: Ludovic =?iso-8859-1?Q?Court=E8s?= Cc: guix-devel On Wed, Jul 11, 2018 at 02:55:45PM +0200, Ludovic Court=C3=A8s wrote: > Now the question is, will it always be possible to run =E2=80=98guix pu= ll=E2=80=99 from > an arbitrary-old Guix? Maybe it will still be impossible sometimes if > the old Guix is really too old. However, I suspect such issues will be > much more rare. There=E2=80=99s essentially a single file that needs t= o be put > under scrutiny to avoid such issues: build-aux/build-self.scm. I think we should have a rescue mode. The nar does not have to be visible on the main download page, but maybe on a rescue page in the manual? A rescue nar would always work.=20 At this point none of my systems runs guix pull any longer. Even getting a build system (from guix) to build the tree is problematic. I realise it may be less of an issue in the future... Mind that, even now, if you change the database layout (e.g. with a source install) guix pull may break. We could have specific rescue nars that go with database versions. That also frees you to change the database :). Call it a transition/rescue nar on time points where things can break.=20 The change to guile2 was such a break, guile-json/tls another and now the new guix pull come to mind. That was dependencies only. We know we are going to change the database in the future... > An archive like you suggest could be useful in those hopefully rare > cases where things break, so it=E2=80=99s a good idea. It should be easy to generate when we do a new release, similar to the binary image, right? We only need a rescue when there is a breaking change, however. They do happen. Pj.