Stacked changes: how FB and Google engineers stay unblocked and ship faster

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  • GitHub repo graphite-cli

    Graphite's CLI makes creating and submitting stacked changes easy.

    We tried manually rebasing too, before building Graphite. The challenge you face with manual rebasing is two parts:

    1) If you update the bottom branch, you need to manually rebase each branch above it. That becomes brutal if your stack is >3 branches.

    2) You cant perform a simple rebase-onto, because you'll copy all commits between the higher branch and trunk. You'd have to perform a three-way rebase, specifying the range of commits you'd like to copy onto the destination. This becomes infeasible by hand.

    Graphite-cli gets around this by tracking branch metadata and storing it in native git refs ( When you rebase a stack, it recursively performs the three-way merge to fix things up smoothly.

    On top of this, git provides no good mechanisms for submitting the stack. Graphite cli can submit/sync your whole stack as individual PRs, and can prune merged branches from the bottom of local stacks. Ends up coming together as a really powerful workflow :)

    The cli is open source here:, with docs here There's also an active Slack community which helps provide input on new features and adjustments.

    Please let me know if you have any other questions!

  • GitHub repo git-branchless

    High-velocity, monorepo-scale workflow for Git

    git-branchless doesn't (yet) aim to integrate with hosted Git providers in any particular way. You just use remotes and push as normal.

    I think the CLI is mostly at parity in terms of features. git-branchless has `git undo` while gt has `git repo sync`. (Tracking issue for git-branchless's sync:

    git-branchless integrates more directly with Git, so you don't need to learn any new commands if you don't want to. If you ruin your stack by amending an old commit, a warning will appear telling you to run `git restack`, which will fix it.

    Besides that, git-branchless does rebase operations in-memory, which makes it faster.

  • OPS

    OPS - Build and Run Open Source Unikernels. Quickly and easily build and deploy open source unikernels in tens of seconds. Deploy in any language to any cloud.

  • GitHub repo ghstack

    Submit stacked diffs to GitHub on the command line

    How is this different from ghstack? (which is what Edward Yang for PyTorch developers to mimic the stacked workflow, although it works with other repos).

  • GitHub repo git-stack

    Stacked branch management for Git

    For anyone interested, I've been collecting notes on various tools in this space: (granted the page doesn't mention git-stack since that is assumed)

  • GitHub repo cockroach

    CockroachDB - the open source, cloud-native distributed SQL database.

    I'm surprised Reviewable[0] hasn't come up in this discussion. It does a great job of allowing stacked code reviews and even handles rebases nicely; the reviewer sees the diff between commit #1 and commit #1' (prime = after rebase).

    CockroachDB[1] has been using it since very early in the project.



  • GitHub repo feedback

    Public feedback discussions for: GitHub for Mobile, GitHub Discussions, GitHub Codespaces, GitHub Sponsors, GitHub Issues and more!

    I proposed a feature along these lines as GitHub feedback. Would love to see more upvotes there if you support the idea!

  • GitHub repo Ansible

    Ansible is a radically simple IT automation platform that makes your applications and systems easier to deploy and maintain. Automate everything from code deployment to network configuration to cloud management, in a language that approaches plain English, using SSH, with no agents to install on remote systems.

    As the parent poster well knows (as they invented it) the trick here is that you write your jobs to install from a checkout the CI system does for you.

    is really nice practical example. What it does isn't even really that important; but it runs a simulation of deploying production code in OpenDev. This is a "devel" job, we deliberately test any changes against all the latest HEADS of the master/main/development branches of projects we use. This is a non-voting job -- a heads up that what you're introducing might be fine now, but there is trouble brewing when our dependencies release their next version. Sometimes that's fine and a known issue, or upstream is broken, and other times it's something totally unique and needs to be fixed (this is why, despite AI being able to write code for you, so far the implications of using that code still need a human in the loop :)

    The "required-projects" tells Zuul what repositories this test needs.

    You can clearly see how it handles various projects having "devel", "main" or "master" branches to pull from to get their latest versions.

    In the "vars" you can see we're setting variables that get passed to the job roles flagging "this is the devel job, don't install the latest release but use the source Zuul will checkout for you from here".

    The amazing thing? If I make a change and this job fails, I may debug it and find that it wasn't actually my fault, but something in upstream Ansible committed recently. I can propose the fix upstream. They do all their CI, and that's fine. But I now put in my change comment


    and magically Zuul will recognise that I want to apply that pull request to the Ansible tree in testing and set it up for me (as noted, Zuul can do this for all sorts of systems, not just github). Additionally, Zuul will not merge the change until the dependency is satisfied -- I can NOT commit broken code!

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    Static code analysis for 29 languages.. Your projects are multi-language. So is SonarQube analysis. Find Bugs, Vulnerabilities, Security Hotspots, and Code Smells so you can release quality code every time. Get started analyzing your projects today for free.

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.

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