I assume you're not suggesting adding ".project" to everyone's Emacs default configurations. It's a user option already (which I do use).

On Fri, Oct 11, 2024 at 1:14 PM Dmitry Gutov <dmitry@gutov.dev> wrote:
On 11/10/2024 11:53, Joost Kremers wrote:
>> That's a natural question, but it would result in different results for
>> "current project" for files in the same directory (which often enough use
>> different major modes).
> What about a single marker that works for any project? This is a
> work-around that Projectile uses and I'm using it with project.el as well,
> with:
>
> ```
> (add-to-list 'project-vc-extra-root-markers ".project")
> ```

That's the recommended course of action if you don't have other
consistent indicators of project root, between your projects.

I'm not a fan of adding a file that has no other purposes, but if people
find this useful, no problem. For personal projects it certainly
shouldn't hurt.

Eric, Jim, how would you like this resolution?