Subject: Re: git submodule using worktrees?

From: Xavier Morel <[email-masked]>
Date: Thu, 12 Mar 2026 09:29:47 +0100

On 12/03/2026 09:20, Kristoffer Haugsbakk wrote:
> On Thu, Mar 12, 2026, at 09:13, Xavier Morel wrote:
>> I have a number of fairly large projects I work with, for that reason I
>> have a bare clone for each and fork off worktrees as needed in order to
>> avoid unnecessary duplication and pulls between them. That works just fine.
>>
>> However when I tried to use submodules to provide a unified view of some
>> of those projects I found out that there's seemingly no way to have
>> submodules created as worktrees (off of a shared repository), at least
>> not built-in. It seems like the submodules do set up some sort of bare
>> repository / worktree situation but do not support passing in an
>> existing repository to worktree off of.
>>
>> `--reference` with `--dissociate` does avoid unnecessary fetches on the
>> initial clone, but they do duplicate objects (and without `--dissociate`
>> has all the issues of a non-static shared alternate), and do require
>> duplicate fetches afterwards to update the submodules, even if the
>> central local repository already has everything.
>>
>> Q1: is there any way to massage the submodules into working off of a
>> central shared repository? Poking around and messing with `.git/modules`
>> didn't really work out but I may have just not poked the right bit,
>> having to set up the submodules by hand (or via a bespoke script) is no
>> issue.
>>
>> Q2: is there any chance submodules will gain more first-class support
>> for worktree-ing off of a local repository in the future
> 
> Does this also not work if these are regular, not-bare clones?

As in make worktrees off of non-bare clones? I don't think that would 
make any difference, to the extent that I tried things out `git 
submodule` does not seem to accept a worktree reference (a file with a 
`gitdir:` path) as repository (in `.git/modules`). Although I may have 
interpreted the error incorrectly.