We'll be saying more about this very soon, but the short version is this: we are not building a GitHub competitor in the way that SourceHut or Codeberg are. We are building infrastructure for enterprises, not a social coding site.

While jj works with git, it doesn't have to. jj has the ability to work with many backends. Git is the popular one in the open source world, but that doesn't mean that other ones are not possible. And that's the core tech we have built.

With the rise of agents, more and more companies are running into the limits of what Git can do. It was never designed for large monorepos, and so there are performance issues, but also features that it's missing, that are important once you start trying to scale things up to an entire organization. Companies like Meta and Google ran into these things well before the present moment, but you don't have to be a FAANG these days to be running into this sort of stuff.

We also understand that incremental adoption is really important, especially for something as fundamental as source control. So our tech also has a git ingress/egress that will work with the core functionality, but more advanced things that git simply can't do will end up requiring using a non-git protocol. jj is the bridge between those two worlds.

I hope that makes sense! We have been in psudeo-stealth for a while now, this is the start of us coming out of our shell a bit and actually talking about what we're doing.

All but one of my employers have used either Github or Gitlab, and at every one of them there were a litany of complaints about whichever one we were using. It's kind of surprising to me that someone might not immediately recognize that there's certainly potential there for something better suited to what companies are actually looking for. Obviously there's no guarantee of success, and maybe the problem is too hard to solve, but that's pretty much how any company starts out!

I’m very excited to see the great work ERSC has/will do. When thinking about where Git lags today, I’ve come up with three categories: UX features and custom data not natively understood by the Git CLI, a stock git-http-backend that doesn’t scale well to moderate monorepo size in server compute / storage, and a wire protocol that isn’t as flexible as it could be for special requests.

But there are so many hooks into the Git workflow today, and I’m struggling to find a “user story” that would not be met by custom Git tooling. UX could be added to Git objects à la Gerrit with custom CLIs, custom Gitoxide ODB and (eventually) ref storage backends can help the server scale, and things like promisor remotes and partial clones can keep things smaller on the client side.

I’m curious what ERSC is able to share publicly about where the scaling fails with the Git specification? Is it the wire format, or the relative speed of upstreaming new things to Git? Or is the side-channel approach for storing rich data in Git objects insufficient in some way?

P.S. I wrote a blog post[1] about this a bit ago. I’m sure I’m missing something. Since I wrote it, I’ve wondered if the lack of deferred conflicts in-tree would be a scaling limiter.

[1] https://jdc.pub/posts/git-jj

As someone trying to compete in this space: will ERSC make the change/commit their unit of code review? It's one of the pet peeves I have with GitHub et al.

Are you guys hiring? (Software Engineer that writes in Rust.)

so most of my guesses about ersc are true, except it is only for enterprise? or do individuals also get access eventually?

[flagged]

The enterprise sounds accurate.

You mention performance issues with Git, but there are performance issues with this blog post.