Skip to content

# Configuration

These are the config settings available to jj/Jujutsu.

## Config files and TOML

`jj` loads several types of config settings:

- The built-in settings. These cannot be edited. They can be viewed in the `cli/src/config/` directory in `jj`'s source repo.

- The user settings. These can be edited with `jj config edit --user`. User settings are located in the user config files, which can be found with `jj config path --user`.

- The repo settings. These can be edited with `jj config edit --repo` and are located in `.jj/repo/config.toml`.

- The workspace settings. These can be edited with `jj config edit --workspace` and are located in `.jj/workspace-config.toml` in the workspace root.

- Settings specified in the command-line.

These are listed in the order they are loaded; the settings from earlier items in the list are overridden by the settings from later items if they disagree. Every type of config except for the built-in settings is optional.

You can enable JSON Schema validation in your editor by adding a `#:schema` reference at the top of your TOML config files. See JSON Schema Support for details.

See the TOML site and the syntax guide for a detailed description of the syntax. We cover some of the basics below.

The first thing to remember is that the value of a setting (the part to the right of the `=` sign) should be surrounded in quotes if it's a string.

### Dotted style and headings

In TOML, anything under a heading can be dotted instead. For example, `user.name = "YOUR NAME"` is equivalent to:

    [user]
    name = "YOUR NAME"

For future reference, here are a couple of more complicated examples,

    # Dotted style
    template-aliases."format_short_id(id)" = "id.shortest(12)"
    colors."commit_id prefix".bold = true

    # is equivalent to:
    [template-aliases]
    "format_short_id(id)" = "id.shortest(12)"

    [colors]
    "commit_id prefix" = { bold = true }

The docs below refer to keys in text using dotted notation, but example blocks will use heading notation to be unambiguous. If you are confident with TOML then use whichever suits you in your config. If you mix dotted keys and headings, you must put the dotted keys before the first heading.

That's probably enough TOML to keep you out of trouble but the syntax guide is very short if you ever need to check.

## User settings

    [user]
    name = "YOUR NAME"
    email = "YOUR_EMAIL@example.com"

Don't forget to change these to your own details!

## UI settings

### Colorizing output

Possible values are `always`, `never`, `debug` and `auto` (default: `auto`). `auto` will use color only when writing to a terminal. `debug` will print the active labels alongside the regular colorized output.

This setting overrides the `NO_COLOR` environment variable (if set).

    [ui]
    color = "never" # Turn off color

### Custom colors and styles

You can customize the colors used for various elements of the UI. For example:

    [colors]
    commit_id = "green"

The following colors are available:

- black
- red
- green
- yellow
- blue
- magenta
- cyan
- white
- default

All of them but "default" come in a bright version too, e.g. "bright red". The "default" color can be used to override a color defined by a parent style (explained below).

You can also use a 6-digit hex code for more control over the exact color used:

    [colors]
    change_id = "#ff1525"

`jj` also supports colors from the ANSI 256-color palette as `ansi-color-<N>`, where `<N>` is a number between 0 and 255:

    [colors]
    commit_id = "ansi-color-81"

If you use a string value for a color, as in the examples above, it will be used for the foreground color. You can also set the background color, reverse colors (swap foreground and background), or make the text bold, italic, or underlined. For that, you need to use a table:

    [colors]
    commit_id = { fg = "green", bg = "#ff1525", bold = true, underline = true }
    change_id = { reverse = true, italic = true }

The key names are called "labels". The above used `commit_id` as label. You can also create rules combining multiple labels. The rules work a bit like CSS selectors. For example, if you want to color commit IDs green in general but make the commit ID of the working-copy commit also be underlined, you can do this:

    [colors]
    commit_id = "green"
    "working_copy commit_id" = { underline = true }

Parts of the style that are not overridden - such as the foreground color in the example above - are inherited from the style of the parent label.

Which elements can be colored is not yet documented, but see the default color configuration for some examples of what's possible.

### Default command

When `jj` is run with no explicit subcommand, the value of the `ui.default-command` setting will be used instead. Possible values are any valid subcommand name, subcommand alias, or user-defined alias (defaults to `"log"`).

    [ui]
    default-command = ["log", "--reversed"]

### Default description

The editor content of a commit description can be populated by the `draft_commit_description` template. `self` is a `Commit` object.

    [templates]
    draft_commit_description = '''
    concat(
      builtin_draft_commit_description,
      "\nJJ: ignore-rest\n",
      diff.git(),
    )
    '''

You can override only the `default_commit_description` value if you like, e.g.:

    [template-aliases]
    default_commit_description = '''
    "

    Closes #NNNN
    "
    '''

### Duplicate commit description

By default, `jj duplicate` copies the descriptions from the original commits. You can customize this behavior by specifying the `duplicate_description` template, which is given a `Commit` object of the original commit.

    [templates]
    duplicate_description = '''
    concat(
      description,
      "\n(cherry picked from commit ",
      commit_id,
      ")"
    )
    '''

### Bookmark listing order

By default, `jj bookmark list` displays bookmarks sorted alphabetically by name. You can customize this sorting behavior by specifying sort keys in your config file:

    [ui]
    bookmark-list-sort-keys = ["name"]

The configuration works identically to using the `--sort` option for `jj bookmark list`. The following sort keys are supported: `name`, `author-name`, `author-email`, `author-date`, `committer-name`, `committer-email`, `committer-date`. Suffix the key with `-` to sort in descending order. Multiple keys can be supplied here, the first key is the most significant.

When the `--sort` option is used with `jj bookmark list`, the configuration is ignored.

### Commit trailers

You can configure automatic addition of one or more trailers to commit descriptions using the `commit_trailers` template.

Each line of the template is an individual trailer, usually in `Key: Value` format.

Trailers defined in this template are deduplicated with the existing description: if the entire line of a trailer is already present, it will not be added again. To deduplicate based only on the trailer key, use the `trailers.contains_key(key)` method within the template.

    [templates]
    commit_trailers = '''
    format_signed_off_by_trailer(self)
    ++ if(!trailers.contains_key("Change-Id"), format_gerrit_change_id_trailer(self))'''

Some ready-to-use trailer templates are available for frequently used trailers:

- `format_signed_off_by_trailer(commit)` creates a "Signed-off-by" trailer using the committer info.
- `format_gerrit_change_id_trailer(commit)` creates a "Change-Id" trailer suitable to be used with Gerrit. It is based Jujutsu's change id.

Existing trailers are also accessible via `commit.trailers()`.

### Diff colors and styles

In color-words and git diffs, word-level hunks are rendered with underline. You can override the default style with the following keys:

    [colors]
    # Highlight hunks with background
    "diff removed token" = { bg = "#221111", underline = false }
    "diff added token" = { bg = "#002200", underline = false }
    # Alternatively, swap colors
    "diff token" = { reverse = true, underline = false }

### Diff format

    [ui]
    # Builtin formats: ":color-words" (default), ":git",
    #                  ":summary", ":stat", ":types", ":name-only"
    # or external command name and arguments (see below)
    diff-formatter = ":git"

#### Color-words diff options

In color-words diffs, changed words are displayed inline by default. Because it's difficult to read a diff line with many removed/added words, there's a threshold to switch to traditional separate-line format. You can also change the default number of lines of context shown.

- `max-inline-alternation`: Maximum number of removed/added word alternation to inline. For example, `<added> ... <added>` sequence has 1 alternation, so the line will be inline if `max-inline-alternation >= 1`. `<added> ... <removed> ... <added>` sequence has 3 alternation.

  - `0`: disable inlining, making `--color-words` more similar to `--git`
  - `1`: inline removes-only or adds-only lines
  - `2`, `3`, ..: inline up to `2`, `3`, .. alternation
  - `-1`: inline all lines

  The default is `3`.

  This parameter is experimental. The definition is subject to change.

- `conflict`: How conflicts are processed and displayed.

  - `"materialize"`: compare materialized contents (default)
  - `"pair"`: compare individual pairs

  This parameter is experimental.

- `context`: Number of lines of context to show in the diff. The default is `3`.

    [diff.color-words]
    max-inline-alternation = 3
    context = 3

#### Git diff options

In git diffs you can change the default number of lines of context shown.

- `context`: Number of lines of context to show in the diff. The default is `3`.

    [diff.git]
    context = 3

### Generating diffs by external command

If `ui.diff-formatter` is not a builtin format, the specified diff command will be called.

    [ui]
    # Use Difftastic by default
    diff-formatter = ["difft", "--color=always", "$left", "$right"]
    # Use tool named "<name>" (see below)
    diff-formatter = "<name>"

The external diff tool can also be enabled by `diff --tool <name>` argument. For the tool named `<name>`, command arguments can be configured as follows.

    [merge-tools.<name>]
    # program = "<name>"  # Defaults to the name of the tool if not specified
    diff-args = ["--color=always", "$left", "$right"]

- `$left` and `$right` are replaced with the paths to the left and right directories to diff respectively.

- `$width` is replaced with the number of terminal columns available to the diff content.

- If `diff-args` is not specified, `["$left", "$right"]` will be used by default.

- If `diff-args = []`, `jj` will refuse to use this tool for diff formatting. This is a way to explicitly state that a certain tool (e.g. `mergiraf`) does not work for viewing diffs.

By default `jj` will invoke external tools with a directory containing the left and right sides. The `diff-invocation-mode` config can change this to file by file invocations as follows:

    [ui]
    diff-formatter = "vimdiff"

    [merge-tools.vimdiff]
    diff-invocation-mode = "file-by-file"

By default `jj` will display a warning when the command exits with a non-success error code. The `diff-expected-exit-codes` config can suppress this warning message for specific exit codes:

    [merge-tools.delta]
    diff-expected-exit-codes = [0, 1]

### Conflict marker style

You can configure which style of conflict markers to use when materializing conflicts:

    [ui]
    # Shows a single snapshot and one or more diffs to apply to it
    conflict-marker-style = "diff"
    # Shows a snapshot for each side and base of the conflict
    conflict-marker-style = "snapshot"
    # Uses Git's "diff3" conflict markers to support tools that depend on it
    conflict-marker-style = "git"

For more details about these conflict marker styles, see the conflicts page.

### Set of immutable commits

You can configure the set of immutable commits via `revset-aliases."immutable_heads()"`. The default set of immutable heads is `builtin_immutable_heads()`, which in turn is defined as `present(trunk()) | tags() | untracked_remote_bookmarks()`. For example, to also consider the `release@origin` bookmark immutable:

    [revset-aliases]
    "immutable_heads()" = "builtin_immutable_heads() | release@origin"

To prevent rewriting commits authored by other users:

    # The `trunk().. &` bit is an optimization to scan for non-`mine()` commits
    # only among commits that are not in `trunk()`.
    [revset-aliases]
    "immutable_heads()" = "builtin_immutable_heads() | (trunk().. & ~mine())"

Ancestors of the configured set are also immutable. The root commit is always immutable even if the set is empty.

Immutable commits (other than the root commit) can be rewritten using the `--ignore-immutable` CLI flag.

Warning

Using `--ignore-immutable` will allow you to rewrite any commit in the history, and all descendants, without warning. Use this power wisely, and remember `jj undo`.

### Behavior of prev and next commands

If you prefer using an "edit-based" workflow, rather than squashing modifications into parent changes, you may find yourself using the `prev` and `next` commands with their `--edit` flag often to move between your changes. You can avoid having to type the `--edit` flag every time you need it by actually making it the default:

    [ui.movement]
    edit = true

You can pass the `--no-edit` flag to `prev` and `next` if you find yourself needing the original behavior.

## List

### Default Template

You can configure the template used when no `-T` is specified.

- `templates.config_list` for `jj config list`

    [templates]
    # Use builtin config list template
    config_list = "builtin_config_list"

If you want to see the config variable origin (type and path) when you do `jj config list` you can add this to your config:

    [templates]
    config_list = "builtin_config_list_detailed"

## Log

### Default revisions

You can configure the revisions `jj log` would show when neither `-r` nor any paths are specified.

    [revsets]
    # Show commits that are not in `main@origin`
    log = "main@origin.."

The default value for `revsets.log` is `'present(@) | ancestors(immutable_heads().., 2) | present(trunk())'`.

### Prioritize Revsets in the Log over @

In some situations the default graph can be hard to read, for example when working with big merges. To improve this behavior you can configure which revset in the `jj log` graph is displayed on the left instead of `@`.

The following example will prioritize the change with the description "megamerge" with a fallback to `trunk()` in case no such change exists:

    [revsets]
    log-graph-prioritize = 'coalesce(description("megamerge\n"), trunk())'

### Default Template

You can configure the template used when no `-T` is specified.

- `templates.evolog` for `jj evolog`
- `templates.log` for `jj log`
- `templates.show` for `jj show`
- `templates.op_log` for `jj op log`
- `templates.op_show` for `jj op show`

    [templates]
    # Use builtin evolog template
    evolog = "builtin_evolog_compact"
    # Use builtin log template
    log = "builtin_log_compact"
    # Use builtin show template
    show = "builtin_log_detailed"
    # Use builtin op log template
    op_log = "builtin_op_log_compact"
    # Use builtin op log template
    op_show = "builtin_op_log_compact"

If you want to see the full description when you do `jj log` you can add this to your config:

    [templates]
    log = "builtin_log_compact_full_description"

### Graph style

    [ui]
    # Possible values: "curved" (default), "square", "ascii", "ascii-large"
    graph.style = "square"

#### Node style

The symbols used to represent commits or operations can be customized via templates.

- `templates.log_node` for commits (with `Option<Commit>` keywords)
- `templates.op_log_node` for operations (with `Operation` keywords)

For example:

    [templates]
    log_node = '''
    coalesce(
      if(!self, "🮀"),
      if(current_working_copy, "@"),
      if(root, "┴"),
      if(immutable, "●", "○"),
    )
    '''
    op_log_node = 'if(current_operation, "@", "○")'

### Wrap log content

If enabled, `log`/`evolog`/`op log` content will be wrapped based on the terminal width.

    [ui]
    log-word-wrap = true

### Display of commit and change ids

Can be customized by the `format_short_id()` template alias.

    [template-aliases]
    # Highlight unique prefix and show at least 12 characters (default)
    'format_short_id(id)' = 'id.shortest(12)'
    # Just the shortest possible unique prefix
    'format_short_id(id)' = 'id.shortest()'
    # Show unique prefix and the rest surrounded by brackets
    'format_short_id(id)' = 'id.shortest(12).prefix() ++ "[" ++ id.shortest(12).rest() ++ "]"'
    # Always show 12 characters
    'format_short_id(id)' = 'id.short(12)'

To customize these separately, use the `format_short_commit_id()` and `format_short_change_id()` aliases:

    [template-aliases]
    # Uppercase change ids. `jj` treats change and commit ids as case-insensitive.
    'format_short_change_id(id)' = 'format_short_id(id).upper()'

Operation ids can be customized by the `format_short_operation_id()` alias:

    [template-aliases]
    # Always show 12 characters
    'format_short_operation_id(id)' = 'id.short(12)'

To get shorter prefixes for certain revisions, set `revsets.short-prefixes`:

    [revsets]
    # Prioritize the current bookmark
    short-prefixes = "(main..@)::"

### Relative timestamps

Can be customized by the `format_timestamp()` template alias.

    [template-aliases]
    # Full timestamp in ISO 8601 format
    'format_timestamp(timestamp)' = 'timestamp'
    # Relative timestamp rendered as "x days/hours/seconds ago"
    'format_timestamp(timestamp)' = 'timestamp.ago()'

`jj op log` defaults to relative timestamps. To use absolute timestamps, you will need to modify the `format_time_range()` template alias.

    [template-aliases]
    'format_time_range(time_range)' = 'time_range.start() ++ " - " ++ time_range.end()'

### Author format

Can be customized by the `format_short_signature()` template alias.

    [template-aliases]
    # Full email address (default)
    'format_short_signature(signature)' = 'signature.email()'
    # Both name and email address
    'format_short_signature(signature)' = 'signature'
    # Username part of the email address
    'format_short_signature(signature)' = 'signature.email().local()'

### Commit timestamp

Commits have both an "author timestamp" and "committer timestamp". By default, jj displays the committer timestamp, but can be changed to show the author timestamp instead.

The function must return a timestamp because the return value will likely be formatted with `format_timestamp()`.

    [template-aliases]
    'commit_timestamp(commit)' = 'commit.author().timestamp()'

### Signature format

Can be enabled with `ui.show-cryptographic-signatures`, and customized with `format_short_cryptographic_signature(sig)` and `format_detailed_cryptographic_signature(sig)`.

Note that the formatting functions take an `Option<CryptographicSignature>`. This allows you to emit a custom message if a signature is not present, but will raise an error if you try to access methods on a signature that is not available.

    [ui]
    # default is false
    show-cryptographic-signatures = true

    [template-aliases]
    'format_short_cryptographic_signature(sig)' = '''
      if(sig,
        sig.status(),
        "(no sig)",
      )
    '''

## Pager

By default, jj will paginate output that would scroll off the screen. It does this by passing output through `less -FRX` on most platforms (on Windows it uses the pager that is built-in to jj).

Which pager to use can be customized by setting `ui.pager`. When choosing a pager, ensure that it either supports color codes or that you disable color (see Colorizing output).

Examples:

    # Pipe output through `less -FRX` (default on non-Windows platforms)
    $ jj config set --user ui.pager "less -FRX"

    # Use the built-in pager (default on Windows)
    $ jj config set --user ui.pager :builtin

    # Use `$PAGER` environment variable if set (on non-Windows platforms)
    $ jj config set --user ui.pager '["sh", "-c", "exec ${PAGER:-less -FRX}"]'

Additionally, paging behavior can be toggled via `ui.paginate` like so:

    [ui]
    # Enable pagination for commands that support it (default)
    paginate = "auto"
    # Disable all pagination, equivalent to using --no-pager
    paginate = "never"

### Builtin pager

Our builtin pager is based on `streampager` but is configured within `jj`'s config. It is configured via the `ui.streampager` table.

#### Key bindings

The built-in pager supports both navigation via arrows and Vim-style navigation. Beyond that, here are some useful keybindings for the pager:

Key | Action
--- | ---
`Ctrl-c` or `q` | Quit
`h` or `F1` | Show all key bindings
`Esc` | Close help or prompt
`\` | Toggle line wrapping
`#` | Toggle line numbers
`Ctrl-r` | Toggle the ruler

The built-in pager does not support mouse input.

#### Wrapping config

Wrapping performed by the pager happens in addition to any wrapping that `jj` itself does.

    [ui.streampager]
    wrapping = "anywhere"  # wrap at screen edge (default)
    wrapping = "word"      # wrap on word boundaries
    wrapping = "none"      # strip long lines, allow scrolling
                           # left and right like `less -S`

#### Auto-exit, clearing the screen on startup or exit

You can configure whether the pager clears the screen on startup or exit, and whether it quits automatically on short inputs. When the pager auto-quits, features like word-wrapping are disabled.

    [ui.streampager]
    # Do not clear screen on exit. Use a full-screen interface for long
    # output only. Like `less -FX`.
    interface = "quit-if-one-page"  # (default).
    # Always use a full-screen interface, ask the terminal to clear the
    # screen on exit. Like `less -+FX`.
    interface = "full-screen-clear-output"
    # Use the alternate screen if the input is either long or takes more
    # than 2 seconds to finish. Similar but not identical to `less -F -+X`.
    interface = "quit-quickly-or-clear-output"

#### Showing the ruler on startup

    [ui.streampager]
    # Start with the ruler showing
    show-ruler = true # (default)
    # Start with the ruler hidden
    show-ruler = false

### Processing contents to be paged

If you'd like to pass the output through a formatter e.g. `diff-so-fancy` before piping it through a pager you must do it using a subshell as, unlike `git` or `hg`, the command will be executed directly. For example:

    [ui]
    pager = ["sh", "-c", "diff-so-fancy | less -RFX"]

Some formatters (like `delta`) require git style diffs for formatting. You can configure this style of diff as the default with the `ui.diff-formatter` setting. For example:

    [ui]
    pager = "delta"
    diff-formatter = ":git"

## Aliases

You can define aliases for commands, including their arguments. For example:

    [aliases]
    # `jj l` shows commits on the working-copy commit's (anonymous) bookmark
    # compared to the `main` bookmark
    l = ["log", "-r", "(main..@):: | (main..@)-"]

This alias syntax can only run a single jj command. However, you may want to execute multiple jj commands with a single alias, or run arbitrary scripts that complement your version control workflow. This can be done, but be aware of the danger:

Warning

The following technique just provides a convenient syntax for running arbitrary code on your system. Using it irresponsibly may cause damage ranging from breaking the behavior of `jj undo` to wiping your file system. Exercise the same amount of caution while writing these aliases as you would when typing commands into the terminal!

This feature may be removed or replaced by an embedded scripting language in the future.

The command `jj util exec` will simply run any command you pass to it as an argument. Additional arguments are passed through. Here are some examples:

    [aliases]
    my-script = ["util", "exec", "--", "my-jj-script"]
    #                            ^^^^
    # This makes sure that flags are passed to your script instead of parsed by jj.
    my-inline-script = ["util", "exec", "--", "bash", "-c", """
    set -euo pipefail
    echo "Look Ma, everything in one file!"
    echo "args: $@"
    """, ""]
    #    ^^
    # This last empty string will become "$0" in bash, so your actual arguments
    # are all included in "$@" and start at "$1" as expected.

> Note: Shebangs (e.g. `#!/usr/bin/env`) aren't necessary since you're already explicitly passing your script into the right shell.

## Editor

The default editor is set via `ui.editor`, though there are several places to set it. The priority is as follows (environment variables are marked with a `$`):

`$JJ_EDITOR` > `ui.editor` > `$VISUAL` > `$EDITOR`

Nano is the default editor (Notepad on Windows) in the absence of any other setting, but you could set it explicitly too.

    [ui]
    editor = "pico"

To use NeoVim instead:

    [ui]
    editor = "nvim"

For GUI editors you possibly need to use a `-w` or `--wait`. Some examples:

    [ui]
    editor = "code -w"       # VS Code
    editor = "code.cmd -w"   # VS Code on Windows
    editor = "bbedit -w"     # BBEdit
    editor = "subl -n -w"    # Sublime Text
    editor = "mate -w"       # TextMate
    editor = ["C:/Program Files/Notepad++/notepad++.exe",
        "-multiInst", "-notabbar", "-nosession", "-noPlugin"] # Notepad++
    editor = "idea --temp-project --wait"   #IntelliJ

Obviously, you would only set one line, don't copy them all in!

## Editing diffs

The `ui.diff-editor` setting affects the default tool used for editing diffs (e.g. `jj split`, `jj squash -i`). If it is not set, the special value `:builtin` is used. It launches a built-in TUI tool (known as scm-diff-editor) to edit the diff in your terminal.

You can try a different tool temporarily by doing e.g. `jj split --tool meld` or you can set the option to change the default. This requires that you have an appropriate tool installed, see for example the instructions for using Meld.

Suggestion: If possible, it is recommended to try an external diff tool like Meld (see below for some other possibilities) for splitting commits and other diff editing, in addition to the built-in diff editor. It is good to know the capabilities of both. The built-in diff editor does not require external tools to be available, is faster for tasks like picking hunks, and does not require leaving the terminal. External tools give you the flexibility of picking out portions of lines from the diff or even arbitrarily editing the text of the files.

If `ui.diff-editor` is a string, e.g. `"meld"`, the arguments will be read from the following config keys.

    [merge-tools.meld]
    # program = "meld"      # Defaults to the name of the tool if not specified
    program = "/path/to/meld" # May be necessary if `meld` is not in the PATH
    edit-args = ["--newtab", "$left", "$right"]

`jj` makes the following substitutions:

- `$left` and `$right` are replaced with the paths to the left and right directories to diff respectively.

- If no `edit-args` are specified, `["$left", "$right"]` are set by default.

- If `edit-args = []`, `jj` will refuse to use this tool for diff editing. This is a way to explicitly state that a certain tool (e.g. `mergiraf`) does not work for diff editing.

Finally, `ui.diff-editor` can be a list that specifies a command and its arguments.

Some examples:

    [ui]
    # Use merge-tools.meld.edit-args
    diff-editor = "meld"  # Or `kdiff3`, or `diffedit3`, ...
    # Specify edit-args inline
    diff-editor = ["/path/to/binary", "--be-helpful", "$left", "$right"]
    # Equivalent to ["binary", "$left", "$right"] arguments by default
    diff-editor = "binary"

### Experimental 3-pane diff editing

We offer two special "3-pane" diff editor configs:

- `meld-3`, which requires installing Meld, and
- `diffedit3`, which requires installing `diffedit3`.

`Meld` is a graphical application that is recommended, but can be difficult to install in some situations. `diffedit3` is designed to be easy to install and to be usable in environments where Meld is difficult to use (e.g. over SSH via port forwarding). `diffedit3` starts a local server that can be accessed via a web browser, similarly to Jupyter.

There is also the `diffedit3-ssh` which is similar to `diffedit3` but does not try to open the web browser pointing to the local server (the URL printed to the terminal) automatically. `diffedit3-ssh` also always uses ports in between 17376-17380 and fails if they are all busy. This can be useful when working over SSH. Open the fold below for more details of how to set that up.

Tips for using `diffedit3-ssh` over SSH
To use `diffedit3` over SSH, you need to set up port forwarding. One way to do this is to start SSH as follows (copy-paste the relevant lines):

    ssh -L 17376:localhost:17376 \
        -L 17377:localhost:17377 \
        -L 17378:localhost:17378 \
        -L 17379:localhost:17379 \
        -L 17380:localhost:17380 \
        myhost.example.com

`diffedit3-ssh` is set up to use these 5 ports by default. Usually, only the first of them will be used. The rest are used if another program happens to use one of them, or if you run multiple instances of `diffedit3` at the same time. Another way is to add a snippet to `~/.ssh/config`:

    Host myhost
        User     myself
        Hostname myhost.example.com
        LocalForward 17376 localhost:17376
        LocalForward 17377 localhost:17377
        LocalForward 17378 localhost:17378
        LocalForward 17379 localhost:17379
        LocalForward 17380 localhost:17380

With that configuration, you should be able to simply `ssh myhost`.

Setting either `ui.diff-editor = "meld-3"` or `ui.diff-editor = "diffedit3"` will result in the diff editor showing 3 panes: the diff on the left and right, and an editing pane in the middle. This allow you to see both sides of the original diff while editing.

If you use `ui.diff-editor = "meld-3"`, note that you can still get the 2-pane Meld view using `jj diff --tool meld`. `diffedit3` has a button you can use to switch to a 2-pane view.

To configure other diff editors in this way, you can include `$output` together with `$left` and `$right` in `merge-tools.TOOL.edit-args`. `jj` will replace `$output` with the directory where the diff editor will be expected to put the result of the user's edits. Initially, the contents of `$output` will be the same as the contents of `$right`.

### `JJ-INSTRUCTIONS`

When editing a diff, jj will include a synthetic file called `JJ-INSTRUCTIONS` in the diff with instructions on how to edit the diff. Any changes you make to this file will be ignored. To suppress the creation of this file, set `ui.diff-instructions = false`.

### Using Meld as a diff editor

Meld is a nice and polished free diff editor. It can be obtained as follows:

- Linux: use your favorite package manager, e.g. `sudo apt install meld`.

- Windows: Meld can be downloaded from https://meldmerge.org/.

- Mac OS: Install Homebrew and run `brew install --cask meld`. This will install both an app in `/Applications/Meld.app` and the command-line `meld` command that `jj` uses. You can read about more details and other options but, as of this writing, this is by far the easiest.

`jj` has two diff editing configurations that use Meld: `meld` for a 2-pane view and `meld-3` for a three-pane view.

There is also a `meld` merge tool that can be useful, but does not support displaying the merge base while merging.

### Using Vim as a diff editor

Using `ui.diff-editor = "vimdiff"` is possible but not recommended. For a better experience, you can follow instructions from the Wiki to configure the DirDiff Vim plugin and/or the vimtabdiff Python script.

## 3-way merge tools for conflict resolution

The `ui.merge-editor` key specifies the tool used for three-way merge tools by `jj resolve`. For example:

    [ui]
    # Use merge-tools.meld.merge-args
    merge-editor = "meld"  # Or "vscode" or "vscodium" or "kdiff3" or "vimdiff"
    # Specify merge-args inline
    merge-editor = ["meld", "$left", "$base", "$right", "-o", "$output"]

The following tools can be used out of the box, as long as they are installed:

- "kdiff3"
- "meld"
- "mergiraf"
- "smerge"
- "vimdiff"
- "vscode"
- "vscodium"

Using VS Code as a merge tool works well with VS Code's Remote Development functionality, as long as `jj` is called from VS Code's terminal.

### Setting up a custom merge tool

To use a different tool named `TOOL`, the arguments to pass to the tool MUST be specified either inline or in the `merge-tools.TOOL.merge-args` key. As an example of how to set this key and other tool configuration options, here is the out-of-the-box configuration of the three default tools. (There is no need to copy it to your config file verbatim, but you are welcome to customize it.)

    [merge-tools.kdiff3]
    # program  = "kdiff3"     # Defaults to the name of the tool if not specified
    merge-args = ["$base", "$left", "$right", "-o", "$output", "--auto"]
    [merge-tools.meld]
    merge-args = ["$left", "$base", "$right", "-o", "$output", "--auto-merge"]

    [merge-tools.vimdiff]
    merge-args = ["-f", "-d", "$output", "-M",
        "$left", "$base", "$right",
        "-c", "wincmd J", "-c", "set modifiable",
        "-c", "set write"]
    program = "vim"
    merge-tool-edits-conflict-markers = true    # See below for an explanation

`jj` makes the following substitutions:

- `$output` (REQUIRED) is replaced with the name of the file that the merge tool should output. `jj` will read this file after the merge tool exits.

- `$left` and `$right` are replaced with the paths to two files containing the content of each side of the conflict.

- `$base` is replaced with the path to a file containing the contents of the conflicted file in the last common ancestor of the two sides of the conflict.

- `$marker_length` is replaced with the length of the conflict markers which should be used for the file. This can be useful if the merge tool parses and/or generates conflict markers. Usually, `jj` uses conflict markers of length 7, but they can be longer if necessary to make parsing unambiguous.

- `$path` is replaced with the path in the repository at which the file will be eventually stored. It is relative to the root directory of the repository and uses `/` as separators.

Unlike `diff-args` or `edit-args`, there is no default value for `merge-args`. If `merge-args` are not specified, the tool cannot be used for conflict resolution.

### Editing conflict markers with a tool or a text editor

By default, the merge tool starts with an empty output file. If the tool puts anything into the output file and exits with the 0 exit code, `jj` assumes that the conflict is fully resolved, while if the tool exits with a non-zero exit code, `jj` assumes that the merge should be canceled. This is appropriate for most graphical merge tools.

For merge tools which try to automatically resolve conflicts without user input, this behavior may not be desired. For instance, some automatic merge tools use an exit code of 1 to indicate that some conflicts were unable to be resolved and that the output file should contain conflict markers. In that case, you could set the config option `merge-tools.TOOL.merge-conflict-exit-codes = [1]` to tell `jj` to expect conflict markers in the output file if the exit code is 1. If a merge tool produces output using Git's "diff3" conflict style, `jj` should be able to parse it correctly, so many Git merge drivers should be usable with `jj` as well.

Some tools (e.g. `vimdiff`) can present a multi-way diff but don't resolve conflict themselves. When using such tools, `jj` can help you by populating the output file with conflict markers before starting the merge tool (instead of leaving the output file empty and letting the merge tool fill it in). To do that, set the `merge-tools.vimdiff.merge-tool-edits-conflict-markers = true` option.

With this option set, if the output file still contains conflict markers after the conflict is done, `jj` assumes that the conflict was only partially resolved and parses the conflict markers to get the new state of the conflict. The conflict is considered fully resolved when there are no conflict markers left. The conflict marker style can also be customized per tool using the `merge-tools.TOOL.conflict-marker-style` option, which takes the same values as `ui.conflict-marker-style`.

## Code formatting and other file content transformations

The `jj fix` command allows you to efficiently rewrite files in complex commit graphs with no risk of introducing conflicts, using tools like `clang-format` or `prettier`. The tools run as subprocesses that take a file content on standard input and repeat it, with any desired changes, on standard output.

This enables the command to format many versions of the same file concurrently and without touching on the working copy. The local files are not and must not be used.

The file is only rewritten if the subprocess produces a successful exit code.

### Configuration

Tools are defined in a table where the keys are arbitrary identifiers and the values have the following properties:

- `command`: The arguments used to run the tool. The first argument is the path to an executable file. Arguments can contain these variables that will be replaced:
  - `$root` will be replaced with the workspace root path (the directory containing the .jj directory).
  - `$path` will be replaced with the repo-relative path of the file being fixed. It is useful to provide the path to tools that include the path in error messages, or behave differently based on the directory or file name.
- `patterns`: List of filesets (see: `jj help -k filesets`), determining which files the tool will affect based on their path. If this list is empty, no files will be affected by the tool. If there are multiple patterns, the tool is applied only once to each file in the union of the patterns.
- `enabled`: Enables or disables the tool. If omitted, the tool is enabled. This is useful for defining disabled tools in user configuration that can be enabled in individual repositories with one config setting.

`jj fix` provides the file content anonymously on standard input, but the name of the file being formatted may be important for include sorting or other output like error messages. To address this, you can use the `$root` and `$path` in your arguments.

### Enforce coding style rules

Suppose you want to use `clang-format` to format your `*.c` and `*.h` files, as well as sorting their `#include` directives.

    [fix.tools.clang-format]
    command = ["/usr/bin/clang-format", "--sort-includes", "--assume-filename=$path"]
    patterns = ["glob:'**/*.c'",
                "glob:'**/*.h'"]

### Sort and remove duplicate lines from a file

`jj fix` can also be used with tools that are not considered code formatters.

Suppose you have a list of words in a text file in your repository, and you want to keep the file sorted alphabetically and remove any duplicate words.

    [fix.tools.sort-word-list]
    command = ["sort", "-u"]
    patterns = ["word_list.txt"]

### Tools stored inside the workspace

Some fix tools may be stored inside the workspace. For example, a binary may be stored inside `node_modules`. Use the `$root` variable to create an absolute path to such a program:

    [fix.tools.biome]

    # Linux and macOS
    command = ["$root/node_modules/@biomejs/cli-linux-x64/biome"]

    # Windows
    command = ["$root\\node_modules\\@biomejs\\cli-win32-x64\\biome.exe"]

### Execution order of tools

If two or more tools affect the same file, they are executed in the ascending lexicographical order of their configured names. Any tool, but the first one to be executed, get as input the content of the file produced by the previous tool. This will remain as a tie breaker if other ordering mechanisms are introduced in the future.

If you use numbers in tool names to control execution order, remember to include enough leading zeros so that, for example, `09` sorts before `10`.

Suppose you want to keep only the 10 smallest numbers in a text file that contains one number on each line. This can be accomplished with `sort` and `head`, but execution order is important.

    [fix.tools.1-sort-numbers-file]
    command = ["sort", "-n"]
    patterns = ["numbers.txt"]

    [fix.tools.2-truncate-numbers-file]
    command = ["head", "-n", "10"]
    patterns = ["numbers.txt"]

### Disabling and enabling tools

Tools can be disabled and enabled with the optional `enabled` config. This allows you to define tools globally but enable them only for specific repositories.

In the user configuration, define a disabled tool for running rustfmt:

    [fix.tools.rustfmt]
    enabled = false
    command = ["rustfmt", "--emit", "stdout"]
    patterns = ["glob:'**/*.rs'"]

Then to use the tool in a specific repository, set the `enabled` config:

    $ jj config set --repo fix.tools.rustfmt.enabled true

## Commit Signing

`jj` can be configured to sign and verify the commits it creates using either GnuPG or SSH signing keys.

To do this you need to configure a signing backend.

Setting the backend to `"none"` disables signing.

### GnuPG Signing

    [signing]
    behavior = "own"
    backend = "gpg"
    ## You can set `key` to anything accepted by `gpg -u`
    ## If not set then defaults to the key associated with `user.email`
    # key = "4ED556E9729E000F"
    # key = "signing@example.com"

By default the gpg backend will look for a `gpg` binary on your path. If you want to change the program used or specify a path to `gpg` explicitly you can set:

    [signing]
    backends.gpg.program = "gpg2"

Also by default the gpg backend will consider key expiry when verifying commit signatures. To consider expired keys as valid you can set:

    [signing]
    backends.gpg.allow-expired-keys = true

#### PKCS#12 Certificates

PKCS#12 certificates can be used to sign commits using the `gpgsm` backend.

    [signing]
    behavior = "own"
    backend = "gpgsm"
    ## You can set `key` to anything accepted by `gpgsm -u`
    ## If not set then defaults to the key associated with `user.email`
    # key = "4ED556E9729E000F"
    # key = "signing@example.com"

By default the gpgsm backend will look for a `gpgsm` binary on your path. If you want to change the program used or specify a path to `gpgsm` explicitly you can set:

    [signing]
    backends.gpgsm.program = "gpgsm"

Also by default the gpgsm backend will consider key expiry when verifying commit signatures. To consider expired keys as valid you can set:

    [signing]
    backends.gpgsm.allow-expired-keys = true

### SSH Signing

    [signing]
    behavior = "own"
    backend = "ssh"
    key = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGj+J6N6SO+4P8dOZqfR1oiay2yxhhHnagH52avUqw5h"
    ## You can also use a path instead of embedding the key
    # key = "~/.ssh/id_for_signing.pub"

By default the ssh backend will look for a `ssh-keygen` binary on your path. If you want to change the program used or specify a path to `ssh-keygen` explicitly you can set:

    [signing]
    backends.ssh.program = "/path/to/ssh-keygen"

When verifying commit signatures the ssh backend needs to be provided with an allowed-signers file containing the public keys of authors whose signatures you want to be able to verify.

You can find the format for this file in the ssh-keygen man page. This can be provided as follows:

    [signing]
    backends.ssh.allowed-signers = "/path/to/allowed-signers"

Additionally, an SSH KRL or list of revoked public keys (see ssh-keygen man page) can be provided with the `revocation-list` option. If a public key is found in this file then any signature relating to it is marked as invalid.

    [signing]
    backends.ssh.revocation-list = "/path/to/revocation-list"

### Manually signing commits

You can use `jj sign`/`jj unsign` to sign/unsign commits manually.

Warning

`jj sign` always signs commits, even if they are already signed by the user. While this is cumbersome for users signing via hardware devices, we cannot reliably check if a commit is already signed without creating a signature (see this issue).

### Automatically signing commits

The `signing.behavior` configuration option has four different options for what to do with signing commits on modification of a change (e.g., rebasing or edits).

- `drop`: do not automatically sign; if a change was signed before modification, drop that signing after modification.
- `keep`: if a change was signed before modification, and it was authored by you, attempt to sign it again after the modification.
- `own`: sign all commits that were authored by you when you modify them.
- `force`: sign all commits after modification, always, even if you are not the author.

Instead of signing all commits during creation when `signing.behavior` is set to `own`, the `git.sign-on-push` configuration can be used to sign commits only upon running `jj git push`. All mutable unsigned commits being pushed will be signed prior to pushing. This might be preferred if the signing backend requires user interaction or is slow, so that signing is performed in a single batch operation.

    # Configure signing backend as before, but lazily signing only on push.
    [signing]
    behavior = "drop"
    backend = "ssh"
    key = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGj+J6N6SO+4P8dOZqfR1oiay2yxhhHnagH52avUqw5h"

    [git]
    sign-on-push = true

## Commit Signature Verification

By default signature verification and display is disabled as it incurs a performance cost when rendering medium to large change logs. You can enable it by setting `ui.show-cryptographic-signatures` to true in your configuration.

If you want to display commit signatures in your templates, you can use `commit.signature()` (see Commit type). The returned CryptographicSignature Type provides methods to retrieve signature details.

## Git settings

### Default colocation

When creating a Git-backed Jujutsu repository, they use "colocated" mode by default, which places the `.git` directory next to the `.jj` directory. Colocation allows some amount of two-way interoperability, but it can perform worse in large repos.

The setting `git.colocate` is a boolean option that controls whether or not the `jj git init` and `jj git clone` commands should create colocated workspace by default. Set `git.colocate` to `false` to disable it.

See Colocated Jujutsu/Git workspaces for more information.

### Default remotes for `jj git fetch` and `jj git push`

By default, if a single remote exists it is used for `jj git fetch` and `jj git push`; however if multiple remotes exist, the default remote is assumed to be named `"origin"`, just like in Git. Sometimes this is undesirable, e.g. when you want to fetch from a different remote than you push to, such as a GitHub fork.

To change this behavior, you can modify the repository configuration variable `git.fetch`, which can be a single remote, or a list of remotes to fetch from multiple places:

    jj config set --repo git.fetch "upstream"
    jj config set --repo git.fetch '["origin", "upstream"]'

By default, the specified remote names matches exactly. You can also use a string pattern to select remotes using patterns:

    jj config set --repo git.fetch "glob:*"
    jj config set --repo git.fetch '["glob:remote*", "glob:upstream*"]'

Similarly, you can also set the variable `git.push` to cause `jj git push` to push to a different remote:

    jj config set --repo git.push "github"

Note that unlike `git.fetch`, `git.push` can currently only be a single remote. This is not a hard limitation, and could be changed in the future if there is demand.

### Automatic tracking of bookmarks

You can configure which bookmarks to track automatically per remote, using the `remotes.<name>.auto-track-bookmarks` config. The value is a string pattern that matches the names of the bookmarks to track. This setting is applied to all new bookmarks, including ones created locally and ones fetched from the remote. For example:

    [remotes.origin]
    auto-track-bookmarks = "glob:*"

This will simply track all bookmarks for the remote "origin". There are various reasons to restrict which bookmarks to track:

- When collaborating with other people via the same remote, you may not want to track all the bookmarks of your collaborators. Similarly, you may not want to push some of your bookmarks to the remote at all; these may only be intended for local use. Many people use a "personal prefix" in their bookmark names. This marks a bookmark as belonging to one person, making it possible to track and push only bookmarks with that prefix. For example, Alice may set her configuration like so:

      [remotes.origin]
      auto-track-bookmarks = "glob:alice/*"

  That way, bookmarks pushed by other people (who probably use a different prefix or none at all) are not tracked automatically. At the same time, Alice can create bookmarks without the prefix for local-only use. You can also configure Jujutsu to use your prefix for generated bookmark names; see the section "Generated bookmark names on push".

- Another reason to restrict the bookmarks to track may be that you're not collaborating with people using the same remote, but a different one. For example, if you make a fork on GitHub, your fork will usually be called "origin", while the repository you forked from is usually called "upstream". In that case, you may want to track all bookmarks from your fork, but only the "main" bookmark from upstream. Here's an example how to achieve that:

      [remotes.origin]
      auto-track-bookmarks = "glob:*"
      [remotes.upstream]
      auto-track-bookmarks = "main"

- Lastly, you may be working on various projects with different conventions for bookmark names. In that case, it can be handy to apply different configuration to different (groups of) repositories. Read about how to do that in the section "Conditional variables".

### Automatic local bookmark creation on `jj git clone`

When cloning a new Git repository, `jj` by default creates a local bookmark tracking the default remote bookmark (such as `main` for `main@origin`.) If you aren't going to update the `main` bookmark locally, the tracking bookmark isn't necessary.

This behavior can be disabled by

    [git]
    track-default-bookmark-on-clone = false

### Abandon commits that became unreachable in Git

By default, when `jj` imports refs from Git, it will look for commits that used to be reachable but no longer are reachable. Those commits will then be abandoned, and any descendant commits will be rebased off of them (as usual when commits are abandoned). You can disable this behavior and instead leave the Git-unreachable commits in your repo by setting:

    [git]
    abandon-unreachable-commits = false

### Generated bookmark names on push

`jj git push --change` generates bookmark names with a prefix of "push-" by default. You can pick a different prefix and formatting by setting the `templates.git_push_bookmark` template. For example:

    [templates]
    git_push_bookmark = '"martinvonz/push-" ++ change_id.short()'

This template should include expressions like `change_id` to generate unique and stable bookmark.

### Set of private commits

You can configure the set of private commits by setting `git.private-commits` to a revset. The value is a revset of commits that Jujutsu will refuse to push. If unset, all commits are eligible to be pushed.

    [git]
    # Prevent pushing work in progress or anything explicitly labeled "private"
    private-commits = "description(glob:'wip:*') | description(glob:'private:*')"

If a commit is in `git.private-commits` but is already on the remote, then it is not considered a private commit. Commits that are immutable are also excluded from the private set.

Private commits prevent their descendants from being pushed, since doing so would require pushing the private commit as well.

### Git subprocessing behavior

Git remote interactions are handled by spawning a `git` subprocess. If `git` is not on your OS path, or you want to specify a particular binary, you can:

    [git]
    executable-path = "/path/to/git"

## Merge settings

### Granularity of hunks

`jj` by default resolves content conflicts by splitting text into line-level hunks and merge them. This can be configured to split hunks further into word-level hunks.

- `line`: split into line hunks (default)
- `word`: split into word hunks

    [merge]
    hunk-level = "line"

### Resolution of same-change conflicts

`jj` by default resolves conflicts if all sides made the same change. This matches what Git and Mercurial do (in the 3-way case at least), but not what Darcs does. It also means that repeated 3-way merging of multiple trees may give different results depending on the order of merging. To turn it off, set `same-change = "keep"`.

- `keep`: leave same-change conflict unresolved
- `accept`: resolve same-change conflict to new value (default)

    [merge]
    same-change = "accept"

## Filesystem monitor

In large repositories, it may be beneficial to use a "filesystem monitor" to track changes to the working copy. This allows `jj` to take working copy snapshots without having to rescan the entire working copy.

This is governed by the `fsmonitor.backend` option. Currently, the valid values are `"none"` or `"watchman"`.

### Watchman

To configure the Watchman filesystem monitor, set `fsmonitor.backend = "watchman"`. Ensure that you have installed the Watchman executable on your system.

You can configure `jj` to use watchman triggers to automatically create snapshots on filesystem changes by setting `fsmonitor.watchman.register-snapshot-trigger = true`.

You can check whether Watchman is enabled and whether it is installed correctly using `jj debug watchman status`.

Note: `watchman` heavily uses `inotify` and sets up a user watch per-file. On large repositories, this may cause `watchman` to fail and commands like `jj status` to take longer than expected. If you experience this run `jj debug watchman status` and tune your `inotify` limits.

## Snapshot settings

### Paths to automatically track

All new files in the working copy that don't match the ignore patterns are tracked by default. You can set the `snapshot.auto-track` to set which paths get automatically tracked when they're added to the working copy. See the fileset documentation for the syntax. Files with paths matching ignore files are never tracked automatically.

If you set `snapshot.auto-track` to a non-default value, untracked files can be tracked with `jj file track`.

You can use `jj file untrack` to untrack a file while keeping it in the working copy. However, first ignore them or remove them from the `snapshot.auto-track` patterns; otherwise they will be immediately tracked again.

### Maximum size for new files

By default, as an anti-footgun measure, `jj` will refuse to add new files to the snapshot that are larger than a certain size; the default is 1MiB. This can be changed by setting `snapshot.max-new-file-size` to a different value. For example:

    [snapshot]
    max-new-file-size = "10MiB"
    # the following is equivalent
    max-new-file-size = 10485760

The value can be specified using a human readable string with typical suffixes; `B`, `MiB`, `GB`, etc. By default, if no suffix is provided, or the value is a raw integer literal, the value is interpreted as if it were specified in bytes.

Files that already exist in the working copy are not subject to this limit.

Setting this value to zero will disable the limit entirely.

### Automatic update of stale working copies

When a working copy becomes stale (meaning the working copy's recorded commit is no longer the current commit for that workspace), `jj` will normally prompt you to update it with `jj workspace update-stale`. You can configure `jj` to automatically update stale working copies by setting:

    [snapshot]
    auto-update-stale = true

This is particularly useful if you have multiple workspaces and want to avoid manually updating each one.

For more information on stale working copies, see the working copy documentation.

## Working copy settings

### EOL conversion settings

This settings serves the same purpose as the `core.autocrlf` git config.

The line endings conversion won't be applied to files detected as binary files via a heuristics1 regardless of the settings. This is similar to git.

    [working-copy]
    # No EOL conversion. Similar to core.autocrlf = false.
    eol-conversion = "none"
    # Apply CRLF to LF EOL conversion when we check files in the backend store from
    # the local file system but not apply EOL conversion when we check out the code
    # from the backend store to the local file system. Similar to core.autocrlf =
    # input.
    eol-conversion = "input"
    # Setting this to "input-output" if you want to have CRLF line endings in your
    # working directory and the repository has LF line endings. Similar to
    # core.autocrlf = true.
    eol-conversion = "input-output"

## Ways to specify `jj` config: details

### User config files

An easy way to find the user config file/directory is:

    jj config path --user

On all platforms, the user's global `jj` configurations are by default loaded in the following precedence order (with later configs overriding earlier ones):

- `$HOME/.jjconfig.toml`
- `<PLATFORM_SPECIFIC>/jj/config.toml` (preferred)
- `<PLATFORM_SPECIFIC>/jj/conf.d/*.toml`

where `$HOME` represents the user's home directory (`%USERPROFILE%` on Windows), and `<PLATFORM_SPECIFIC>` represents the platform-specific configuration directory shown in the table below. The platform-specific location is recommended for better integration with platform services.

The files in the `conf.d` directory are loaded in lexicographic order. This allows configs to be split across multiple files and combines well with Conditional Variables.

Platform | Location of `<PLATFORM_SPECIFIC>` dir | Example config file location
--- | --- | ---
Linux and macOS | `$XDG_CONFIG_HOME` or `$HOME/.config` | `/home/alice/.config/jj/config.toml`
Windows | `{FOLDERID_RoamingAppData}` | `C:\Users\Alice\AppData\Roaming\jj\config.toml`

The location of the `jj` user config files/directories can also be overridden with the `JJ_CONFIG` environment variable. If it is not empty, it will be used instead of any configuration files in the default locations. If it is a path to a TOML file, then that file will be loaded instead. If it is a path to a directory, then all the TOML files in that directory will be loaded in lexicographic order and merged. Multiple paths can be specified by separating them with a platform-specific path separator (`:` on Unix-like systems, `;` on Windows).

For example, the following could be used to run `jj` without loading any user configs:

    JJ_CONFIG= jj log       # Ignores any settings specified in the config file.

### JSON Schema Support

Many popular editors support TOML file syntax highlighting and validation. To enable schema validation in your editor, add this line at the top of your TOML config files:

    #:schema https://docs.jj-vcs.dev/latest/config-schema.json

This enables features like:

- Autocomplete for config keys
- Type checking of values
- Documentation on hover
- Validation of settings

Here are some popular editors with TOML schema validation support:

- VS Code

  - Install Even Better TOML

- Neovim/Vim

  - Use with nvim-lspconfig and taplo

- Helix

  - Install taplo

- JetBrains IDEs (IntelliJ, PyCharm, etc)

  - Install TOML plugin

- Emacs

  - Install lsp-mode and toml-mode
  - Configure taplo as the LSP server

### Specifying config on the command-line

You can use one or more `--config`/`--config-file` options on the command line to specify additional configuration settings. This overrides settings defined in config files or environment variables. For example,

    # Must not have spaces around the `=`
    jj --config ui.color=always --config ui.diff-editor=meld split

Config value should be specified as a TOML expression. If string value isn't enclosed by any TOML constructs (such as array notation), quotes can be omitted. Here is an example with more advanced TOML constructs:

    # Single quotes and the '\' are interpreted by the shell and assume a Unix shell
    # Double quotes are passed to jj and are parsed as TOML syntax
    jj log --config \
      'template-aliases."format_timestamp(timestamp)"="""timestamp.format("%Y-%m-%d %H:%M %:::z")"""'

To load an entire TOML document, use `--config-file`:

    jj --config-file=extra-config.toml log

### Conditional variables

You can conditionally enable config variables by using `--when`.

#### Using `[[--scope]]` tables

Variables defined in `[[--scope]]` tables are expanded to the root table. `--when` specifies the condition to enable the scope table.

If no conditions are specified, the table is always enabled. If multiple conditions are specified, their intersection is used.

    [user]
    name = "YOUR NAME"
    email = "YOUR_DEFAULT_EMAIL@example.com"

    # override user.email if the repository is located under ~/oss
    [[--scope]]
    --when.repositories = ["~/oss"]
    [--scope.user]
    email = "YOUR_OSS_EMAIL@example.org"

    # override ui.pager on specific machines
    [[--scope]]
    --when.hostnames = ["work-laptop", "work-desktop"]
    [--scope.ui]
    pager = "delta"

    # disable pagination for `jj status`, use `delta` for `jj diff` and `jj show`
    [[--scope]]
    --when.commands = ["status"]
    [--scope.ui]
    paginate = "never"
    [[--scope]]
    --when.commands = ["diff", "show"]
    [--scope.ui]
    pager = "delta"

#### Using multiple files

`--when` can also be used on the top level of a TOML file, which is convenient when splitting your config across multiple files. The behavior of conditions are the same as when using `[[--scope]]` tables.

    # In $XDG_CONFIG_HOME/jj/config.toml
    [user]
    name = "YOUR NAME"
    email = "YOUR_DEFAULT_EMAIL@example.com"

    # In $XDG_CONFIG_HOME/jj/conf.d/work.toml
    --when.repositories = ["~/the/work/repo"]

    [user]
    email = "YOUR_WORK_EMAIL@workplace.com"

    [revset-aliases]
    work = "heads(::@ ~ description(exact:''))::"

    [aliases]
    wip = ["log", "-r", "work"]

#### Available condition keys

- `--when.repositories`: List of paths to match the repository path prefix.

  Paths should be absolute. Each path component (directory or file name, drive letter, etc.) is compared case-sensitively on all platforms. A path starting with `~` is expanded to the home directory. On Windows, directory separator may be either `\` or `/`. (Beware that `\` needs escape in double-quoted strings.)

  Use `jj root` to see the workspace root directory. Note that the repository path is in the main workspace if you're using multiple workspaces with `jj workspace`.

- `--when.workspaces`: List of paths to match the workspace path prefix.

  The same concerns about the path as for `--when.repositories` applies.

  Use `jj root` to see the workspace root directory.

- `--when.hostnames`: List of hostnames to match against the `operation.hostname` config setting.

  Hostnames are compared case-sensitively and must match exactly.

      --when.hostnames = ["work-laptop"]               # matches only "work-laptop"
      --when.hostnames = ["home-desktop", "laptop"]    # matches "home-desktop" OR "laptop"

- `--when.commands`: List of subcommands to match.

  Subcommands are space-separated and matched by prefix.

      --when.commands = ["file"]        # matches `jj file show`, `jj file list`, etc
      --when.commands = ["file show"]   # matches `jj file show` but *NOT* `jj file list`
      --when.commands = ["file", "log"] # matches `jj file` *OR* `jj log` (or subcommand of either)

- `--when.platforms`: List of platforms to match.

  The values are defined by both `std::env::consts::FAMILY` and `std::env::consts::OS`.

      --when.platforms = ["windows"]            # matches only Windows
      --when.platforms = ["linux", "freebsd"]   # matches Linux or and FreeBSD, but not macOS
      --when.platforms = ["unix"]               # matches anything in the Unix family (Linux, FreeBSD, macOS, etc.)

1. To detect if a file is binary, Jujutsu currently checks if there is NULL byte in the file which is different from the algorithm of `gitoxide` or `git`. Jujutsu doesn't plan to align the binary detection logic with git. ↩