josh VS jj

Why use submodules when you can properly vendor the upstream git, and export/import commits without breaking hashes on either side?

https://github.com/josh-project/josh

We've been using josh at TVL for years and it's just amazing.

Scalar explicitly does not implement the virtualized filesystem the OP is referring to. The original Git VFS for Windows that Microsoft designed did in fact do this, but as your second link notes, Microsoft abandoned that in favor of Scalar's totally different design which explicitly was about scaling repositories without filesystem virtualization.

There's a bunch of related features they added to Git to achieve scalability without virtualization. Those are all useful and Scalar is a welcome addition. But the need for a virtual filesystem layer for large-scale repositories is still a very real one. There are also some limitations that aren't ideal; for example Git's partial clones IIRC can only be used as a "cone" applied to the original filesystem hierarchy. More generalized designs would allow mapping any arbitrary paths in the original repository to any other path in the virtual checkout. Tools like Josh can do this today with existing Git repositories[1]. That helps you get even sparser and smaller checkouts.

The Git for Windows that was referenced isn't even that big at 300GB, by the way. Game studios regularly have repositories that exist at multi-terabyte size, and they have also converged on similar virtualization solutions. For example, Destiny 2 uses a "virtual file synchronization" layer called VirtualSync[2] that reduced the working size of their checkouts by over 98%, multiple terabytes of savings per person. And in a twist of fate, VirtualSync was implemented thanks to a feature called "ProjFS" that Microsoft added to Windows... which was motivated originally by the Git VFS for Windows they abandoned!

[1] https://github.com/josh-project/josh

[2] https://www.gdcvault.com/play/1027699/Virtual-Sync-Terabytes...

Good overview, I know these sorts of pains well. Lots of hard questions and few definitive wins/right answers. How to organize a massive repository out in the open is still an open question. On that note, recently, I've been experimenting with this project called josh, which basically is like 'git subtree on extreme steroids, functioning as a git proxy':

https://josh-project.github.io/josh/

It basically lets you unify/view many repositories as a single one, or equivalent to split a mono-repo into smaller sized units of work for CI, specific teams, etc. It's bidirectional, so you push and pull from josh and everything goes into a single linear history in the mono repo. And because it's bidirectional, people in the mono-repo can still do things like make large-scale atomic changes across all sub-repositories, and those get reflected.

Josh currently isn't suitable for a lot of workloads due to various reasons (authentication is one that stands out), but it's actually the first tool I have seen that manages to offer BitKeeper-like "subtrees" that work really well, at scale, for large repos and teams. It requires some care to make sure "sub-trees" can be usable units of work, but it was one of the best features of BK in my opinion and really great for people doing one-off contributions, or isolating trees/changes to specific developers.

I'd be interested to know if there are other open alternatives to this. It's a nice point in the design space between solutions like "integrate with the filesystem layer to do sparse clones" or "just split up the repos."

With regard to repo composition, I have been following this project: https://github.com/josh-project/josh

Jujutsu is along the lines of what you describe: https://github.com/martinvonz/jj

You can drop it in and work seamlessly from git repos

Pull Requests (or Merge Requests) are merged only when (1) all of the automated tests pass; and (2) enough necessary reviewers have indicated approval.

Git doesn't tell you when it's necessary to have full test coverage and manual infosec review in development cycles that produce releases, and neither do Pull Requests.

https://westurner.github.io/hnlog/#comment-19552164 ctrl-f hubflow

It looks like datasift's gitflow/hubflow docs are 404'ing, but the original nvie blog post [1] has the Git branching workflow diagrams; which the wpsharks/hubflow fork [3] of datasift/gitflow fork [2] of gitflow [1]has a copy of in the README:

[1] https://github.com/nvie/gitflow

[2] https://github.com/datasift/gitflow

[3] https://github.com/wpsharks/hubflow?tab=readme-ov-file

https://learngitbranching.js.org/ is still a great resource, and it could work on mobile devices.

The math of VCS deltas and mutable and immutable content-addressed DAG nodes identified by 2^n bits describing repo/$((2*inf)) bits ;

>> "ugit – Learn Git Internals by Building Git in Python" https://www.leshenko.net/p/ugit/

SLSA.dev is a social construct atop e.g. git, which is really a low-level purpose-built tool and Perl and now Python porcelain.

jj (jujutsu) is a git-compatible VCS CLI: https://github.com/martinvonz/jj

"Ask HN: Best Git workflow for small teams" (2016)

You will probably like Jujutsu, which takes much inspiration from Mercurial: https://github.com/martinvonz/jj

It isn't a 1-to-1 clone, either. But tools like revsets are there, cset evolution is "built in" to the design, etc. There is no concept of phases, we might think about adding that, but there is a concept of immutable commits (so you don't overwrite public ones.)

It also has many novel features that make it stand out. We care a lot about performance and usability. Give it a shot. I think you might be pleasantly surprised.

Disclosure: I am a developer of Jujutsu. I do it in my spare time.

I have created a discussion. Thank you both

https://github.com/martinvonz/jj/discussions/2691

> why don't version control systems (especially ones that can change history) have undo/redo functionality out of the box?

It's true. And Jujutsu has undo functionality out of the box, too. It's not just Sapling. :) https://github.com/martinvonz/jj

Git made the only choice a popular VCS can make. History rewrites will exist, period. If you're opposed to history rewrites, then git gives you the tools to ensure the repos you control are not rewritten, and that's all it can do in a world where people have control of their own computers.

If Fossil ever becomes as popular as git, people will create software that allows history rewriting in Fossil, and that's fine. People will do what they want on their own computer, and I think it's morally wrong to try and stop that.

Another user in this thread linked to jj [0], an alternative git client that does some pretty weird things. For example, it replaces the working tree with a working commit and commits quite often. I like git and that seems weird to me, but I'm not offended, people can do what they want on their own computer and I have the tools to ensure repos under my control are not effected. That's all I can hope for.

[0]: https://github.com/martinvonz/jj

I recently found out about another project called jj: https://github.com/martinvonz/jj. It takes inspiration from Pijul and others but is git-compatible.

https://github.com/martinvonz/jj

I think maybe both fossil and bitkeeper are more intuitive too.

Did you try any of those?