Subject: Re: When should we release Git 3.0?

From: Junio C Hamano <[email-masked]>
Date: Thu, 02 Oct 2025 08:32:38 -0700

Patrick Steinhardt <[email-masked]> writes:

> Once we have roadmaps, we should set a strict deadline that takes them
> into account. Any hosting provider or implementation of Git that doesn't
> provide a roadmap will not be taken into account in our planning.

Works fine as long as we assume everybody that matters will
eventually want to move away from SHA-1.

 - If a stakeholder gives a roadmap that has no SHA-256 in their
   future, in other words, if they are content to serve only the
   SHA-1 projects, what's the impact to them?  We are not dropping
   the support for SHA-1 in the sense that if you clone from an
   existing SHA-1 repository you'll get an SHA-1 repository and you
   can push and fetch between them just fine, so presumably that is
   fine as well.

 - If a stakeholder gives a roadmap with SHA-256 so far into the
   future that we cannot wait, what's the impact to them?  Their
   customers that want SHA-256 earlier than they can supply could
   move to other hosting or implementation, but not really.  Both
   hosting providers and Git implementations have components that
   are move than Git that are hard to migrate, like issue trackers,
   CI services, workflow tools, etc., that make their customers
   captive audience [*].

 - If a stakeholder has a roadmap with SHA-256 in line with our
   timeframe, do we still need to assess the impact to them, or as
   long as we and they work hard to stick to the plan, we all will
   be happy?

> We should of course actively reach out to the projects that we're aware
> of so that they have a chance to provide such a roadmap in the first
> place.

[Footnote]

 * Issue trackers and review logs that are federated, possibly using
   Git database for storage and transfer, may allow projects and
   users to freely roam across hosting sites, but there is no strong
   incentive for the hosting sites to fund such an effort X-<.