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# Jujutsu

![](./jj-logo.png)

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## What is it?

* New version control software (VCS)
* Separation of **frontend** and **backend**
* Compatible with git
* Slowly replacing git cli at Google (askip)
* Aiming for a simpler workflow

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## No branch, only revisions

![](./jj_02.png)
<revision id> <author> <date> <branch> <commit id>

- @ working copy
- ◆ immutable
- × conflict

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## Embrace the DETACHED HEAD

- No need to be at the tip of a branch
- Easy to change the current revision (no rebase step)
- Each revision has a scope, you can switch / split / squash
- You can modify other branches, not only the current one (there is none)

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## Immutable revisions

- New concept
- By default `master` is immutable, sane choice
- Clearly express what would create conflict, even local copy cannot change
- You can override it (but don't)

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## No staging area, everything is logged

- You need a good gitignore
- You can always switch commits without loss
- You might want to recreate a "staging" commit

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## Conflicts are ok

- Conflicts are recorded but never stop a rebase
- Conflicted commits are annotated
- You can safely rebase, deal with conflicts later on
- No need to mark as resolved

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## Branches, bookmarks

- Branches (git) = bookmarks (jujutsu)
- Optional during dev
- Mandatory when pushing
- Stick to revision, manual step to update
- Tracked bookmarks are updated during fetch
  - No sync conflict between a local copy and its remote

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## Back to git?

- A way back is always possible
- git view gets confused in detached HEAD

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## Tooling

- Battery included
  - CLI tool for splitting commits
- Git tools not compatible

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## Takeaway

- 🤩 Good when dealing with multiple tracks
- 😔 Need to explicitely specify branch when pushing commits
- Small improvements, not game-changing
- 😔 No ecosystem, but it's growing (TUI)
- Native backend (not ready yet) would remove a lot of friction

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## Worth the switch?

# ✋ Not yet

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# References

- [Official website](https://jj-vcs.github.io/jj/)
  - [GUI & TUI](https://github.com/jj-vcs/jj/wiki/GUI-and-TUI)