I continue not to understand much of the point of this. I don't recognize the git workflow the author is talking about, and neither do I see the point of stacked PRs. Commits are fine as a unit of isolating work, and rebasing to keep that neat is not difficult.
How many PR's do y'all tend to have in flight at once? I sometimes think being a native (C++) developer makes me have a different take on some of this. Maybe if I was a JS dev making quick changes with 5 PR's a day I'd care more about this.
I totally agree. I've never understood the push back against clean "railroad tracks" (i.e. rebasing instead of merge commits). It's simple, scales nicely and gives you a lot of options. Once you start allowing merge commits in the tree, things can get messy but with a bit of discipline, it elegantly solves every version control use-case I can think of, or have encountered, including at scale.
If you have a large PR with multiple nontrivial commits I think you should merge it so the intermediate states are the same ones that were originally tested. Otherwise you could break bisects, among other issues.
I work primarily in c++ and fully agree with the author. I think it makes more sense in the context of larger teams, possibly also monorepos. Review speed (both latency of feedback and how thorough your reviewers are), presubmit test runtime, flake rate, etc can lead to it taking a few days to get work submitted. In some cases you don't want to land work until you've finished a milestone of some sort. If others work on similar files to you, you will end up with several rounds of rebase conflicts to deal with too.
Stacked PRs is mostly a way to avoid thousand- or tens-of-thousands- LOC branches, which makes each PR meaningfully reviewable. You need a good code review process for it to become useful. It’s very pleasant once you are accustomed to it.
I’ve seen successful teams that regularly do reviews of massive PRs and feel this serves them well enough. I suspect it just places a lot more trust on the developers to get the details right so reviewers only look at larger design issues.
The language of choice is not relevant. Even before AI, one can accumulate thousands of lines of c++ easily.
Working in growing monorepo I find git tragically annoying and lacking. On regular basis I stumble upon situations where I work on one thing, but it causes changes in other package and I have no clear no way to say: this changes go to branch #1, this other set of changes to branch #2, and another small fix to branch #3. Branch #1 depends on the others and once #2 and #3 get merged it should merge to master cleanly with no ceremony.
Switching branches is not a solution, cause all of this changes develop at the same time.
Neither worktrees nor stashes are even nearby being a viable solution.
Unless someone enlightens me and explains how to achieve this flow easily in git I’ll be looking for better solutions. I just installed jj and I do hope it will bring some relief.
To be fair, before working in monorepo I did not have this kind of issues, or at least not that annoying. And yes, LLMs made the issue even bigger, cause it happens more often that while I’m coding on main feature I’ll write to Codex: „btw, fix this one thing while I’m busy with main tasks”, so my workstream is actually more tree-shaped than stream shaped.
You should look into `update-refs` functionality. By default git treats each branch independently, but with update-refs, git tracks pointers to branches and creates a dependency chain.
I admit the diagrams and struggles the author describes are far past my own usage of git. And like they identify at the end of the article, for truly complex git operations today I use AI. I haven’t rebased manually for a while. Forget rewriting commit messages!
> Companies like Meta have enjoyed in-house systems that run circles around it for almost a decade.
Well yes because git was supposed to be completely distributed. You can design a system which has this feature but then it wouldn't be as distributed as git, making unrelated forks second class citizens. It might still be a good idea for tool to have it but it is not strictly a better/worse scenario.
> Mutability
I think i can mostly agree to this. I do wonder if people never work in a scenario where they are only committing partial state and not complete state. Nevertheless being able to track and not losing uncommitted state is a strict improvement.
This has pretty pictures but its verbosity and frankly made-up complexity is making me not take it as seriously as I perhaps should.
The way I'd handle rebasing stacked PRs/branches is to rebase the very last one. Then simply `git branch -f a-branch <logical same point on rebased>` for each of the others, done.
I worked on a project that had weekly releases. We had git submodules, and submodules of that, and on rare occasions a 4th repo. I would manually keep those all up to date with rebases pinning each submodule to the logical new points. It all became muscle memory. The lesson I learned is don't use submodules unless you really need to. (All the repos were our own.)
JJ may be great but a stawman isn't going to sell it to me.
Now I can tell an AI to rebase a stack and as long as there weren't any conflicts easily check the results.
Everyone has things that bug them, git isn't one of mine (today :-). Instead I have a custom keyboard layout that no one else uses that makes me feel better, but I don't go around telling everyone they should switch--unless you're curious[0].
How many PR's do y'all tend to have in flight at once? I sometimes think being a native (C++) developer makes me have a different take on some of this. Maybe if I was a JS dev making quick changes with 5 PR's a day I'd care more about this.
I’ve seen successful teams that regularly do reviews of massive PRs and feel this serves them well enough. I suspect it just places a lot more trust on the developers to get the details right so reviewers only look at larger design issues.
The language of choice is not relevant. Even before AI, one can accumulate thousands of lines of c++ easily.
A piece of software looking for a problem to solve.
Do you remember the TV ads where people were acting like imbeciles to sell you their junk products for 3 easy payments of 19.99?
Switching branches is not a solution, cause all of this changes develop at the same time.
Neither worktrees nor stashes are even nearby being a viable solution. Unless someone enlightens me and explains how to achieve this flow easily in git I’ll be looking for better solutions. I just installed jj and I do hope it will bring some relief.
To be fair, before working in monorepo I did not have this kind of issues, or at least not that annoying. And yes, LLMs made the issue even bigger, cause it happens more often that while I’m coding on main feature I’ll write to Codex: „btw, fix this one thing while I’m busy with main tasks”, so my workstream is actually more tree-shaped than stream shaped.
> Companies like Meta have enjoyed in-house systems that run circles around it for almost a decade.
Based on Mercurial… the VCS I enjoyed using.
Well yes because git was supposed to be completely distributed. You can design a system which has this feature but then it wouldn't be as distributed as git, making unrelated forks second class citizens. It might still be a good idea for tool to have it but it is not strictly a better/worse scenario.
> Mutability
I think i can mostly agree to this. I do wonder if people never work in a scenario where they are only committing partial state and not complete state. Nevertheless being able to track and not losing uncommitted state is a strict improvement.
> workflows
Aren't worktrees enough here?
The way I'd handle rebasing stacked PRs/branches is to rebase the very last one. Then simply `git branch -f a-branch <logical same point on rebased>` for each of the others, done.
I worked on a project that had weekly releases. We had git submodules, and submodules of that, and on rare occasions a 4th repo. I would manually keep those all up to date with rebases pinning each submodule to the logical new points. It all became muscle memory. The lesson I learned is don't use submodules unless you really need to. (All the repos were our own.)
JJ may be great but a stawman isn't going to sell it to me.
Now I can tell an AI to rebase a stack and as long as there weren't any conflicts easily check the results.
Everyone has things that bug them, git isn't one of mine (today :-). Instead I have a custom keyboard layout that no one else uses that makes me feel better, but I don't go around telling everyone they should switch--unless you're curious[0].
[0] https://github.com/qwickly-org/Qwickly