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Setup

Installation​

Start by installing jj, following the installation instructions.

Verify the installation was successful:

Run
jj version
Expected output (similar)
jj 0.24.0-32d2a85539254e9d96f9819072fa5c6ac70dd1e4
Overview of commands
jj -h

Config​

Basics​

Set some global (for your user) configuration. Adapt as needed.

Set your preferred text editor
# Note if you have an EDITOR env variable you can skip this
jj config set --user ui.editor vim

## To copy the setting from Git use the following instead:
#jj config set --user ui.editor "`git config --get core.editor`"
Set email and name
jj config set --user user.email ME@EXAMPLE.COM
jj config set --user user.name "MY NAME"

## To copy the settings from Git use the following instead:
#jj config set --user user.email "`git config --get user.email`"
#jj config set --user user.name "`git config --get user.name`"

Make jj default to jj log, which is very convenient. Otherwise you'll have to type jj log instead of jj every time you want to see the history, which is frequently.

jj config set --user ui.default-command log
Repository-specific configuration

If you are inside a repository, you can set configuration that only applies to that repository. Use --repo instead of --user.

(Optional) Make "log" more verbose​

If you are curious, see the default value
jj config get revsets.log
Change the value
jj config set --user revsets.log "present(@) | ancestors(immutable_heads().., 7) | present(trunk())"

(Optional) Manually edit the config file​

See location of config file
jj config path --user
Open the config file in an editor
jj config edit --user

Clone Repository​

Clone the repository
jj git clone --colocate https://github.com/omarkohl/jj-tutorial
cd jj-tutorial
Colocate

--colocate allows you to use both Git commands and Ju Jutsu commands in the same repository. If you don't use that option then Ju Jutsu will still keep an internal Git repository inside the .jj/ directory but you will not be able to execute any git ... commands yourself.

See the log (history)
jj

Log output

(Optional) Try it in another Git repository​

If you have any local Git repository I encourage you to try using jj in it too:

cd path/to/my/repo
jj git init --colocate

Now you can use jj with all the things you learn in this tutorial.

If you ever want to get rid of jj in this repository:

cd path/to/my/repo
rm -rf .jj/

That's it, as if jj had never been there! Any commits you created, rebased etc. via jj will of course be there since jj synchronizes the jj data with Git. It will just look as if everything had been done with Git.

(Optional) Shell completion​

If you use bash, you can add the following to your ~/.bashrc:

source <(jj util completion bash)

See more examples for other shells.

(Optional) Live 'jj log'​

A convenient way of permanently seeing the current state of your log is to run this command in a separate terminal window and have it open next to your work.

cd path/to/repo
watch --color jj --ignore-working-copy log --color=always

See an explanation and alternatives here.

Takeaways​

Key points. As QA because of active recall. Try to come up with the answer yourself before looking 😉

  1. What is the relationship between Ju Jutsu and Git?
  2. If you forget about a particular command, how do you refresh your memory?