jj/docs/config.md

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 file, 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.

• 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.

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 }

Jujutsu favors the dotted style in these instructions, if only because it's easier to write down in an unconfusing way. If you are confident with TOML then use whichever suits you in your config. If you mix dotted keys and headings, 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"
user.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"

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, or make the text bold or underlined. For that, you need to use a table:

colors.commit_id = { fg = "green", bg = "#ff1525", bold = true, underline = 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"
colors."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 parent style.

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.

[templates]
draft_commit_description = '''
concat(
  description,
  surround(
    "\nJJ: This commit contains the following changes:\n", "",
    indent("JJ:     ", diff.stat(72)),
  ),
)
'''

The value of the ui.default-description setting can also be used in order to fill in things like BUG=, TESTED= etc.

ui.default-description = "\n\nTESTED=TODO"

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 }

Diff format

# Possible values: "color-words" (default), "git", "summary"
ui.diff.format = "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.

• 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.

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

Generating diffs by external command

If ui.diff.tool is set, the specified diff command will be called instead of the internal diff function.

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

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.tool = "vimdiff"

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

Set of immutable commits

You can configure the set of immutable commits via revset-aliases."immutable_heads()". The default set of immutable heads is trunk() | tags() | untracked_remote_bookmarks(). For example, to prevent rewriting commits on main@origin and commits authored by other users:

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

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

Log

Default revisions

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

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

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

Graph style

# Possible values: "curved" (default), "square", "ascii", "ascii-large"
ui.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()'

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

# Prioritize the current bookmark
revsets.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.username()'

Allow "large" revsets by default

Certain commands (such as jj rebase) can take multiple revset arguments, but default to requiring each of those revsets to expand to a single revision. This restriction can be overridden by prefixing a revset that the user wants to be able to expand to more than one revision with the all: modifier.

Another way you can override this check is by setting ui.always-allow-large-revsets to true. Then, jj will allow every one of the revset arguments of such commands to expand to any number of revisions.

# Assume `all:` prefix before revsets whenever it would make a difference
ui.always-allow-large-revsets = true

Pager

The default pager is can be set via ui.pager or the PAGER environment variable. The priority is as follows (environment variables are marked with a $):

ui.pager > $PAGER

less -FRX is the default pager in the absence of any other setting, except on Windows where it is :builtin.

The special value :builtin enables usage of the integrated pager called minus. See the docs for the minus pager for the key bindings and some more details.

If you are using a standard Linux distro, your system likely already has $PAGER set and that will be preferred over the built-in. To use the built-in:

jj config set --user ui.pager :builtin

It is possible the default will change to :builtin for all platforms in the future.

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

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

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 setting. For example:

[ui]
pager = "delta"

[ui.diff]
format = "git"

Aliases

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

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

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

Pico 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
ui.editor = "code.cmd -w"   # VS Code on Windows
ui.editor = "bbedit -w"     # BBEdit
ui.editor = "subl -n -w"    # Sublime Text
ui.editor = "mate -w"       # TextMate
ui.editor = ["C:/Program Files/Notepad++/notepad++.exe",
    "-multiInst", "-notabbar", "-nosession", "-noPlugin"] # Notepad++
ui.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 tool used for editing diffs (e.g. jj split, jj squash -i). The default is the special value :builtin, which launches a built-in TUI tool (known as scm-diff-editor) to edit the diff in your terminal.

jj makes the following substitutions:

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

If no arguments are specified, ["$left", "$right"] are set by default.

For example:

# Use merge-tools.kdiff3.edit-args
ui.diff-editor = "kdiff3"
# Specify edit-args inline
ui.diff-editor = ["kdiff3", "--merge", "$left", "$right"]

If ui.diff-editor consists of a single word, e.g. "kdiff3", the arguments will be read from the following config keys.

# merge-tools.kdiff3.program = "kdiff3"      # Defaults to the name of the tool if not specified
merge-tools.kdiff3.edit-args = [
    "--merge", "--cs", "CreateBakFiles=0", "$left", "$right"]

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 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:

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

The "vscode", "vscodium", "meld", "kdiff3", and "vimdiff" tools can be used out of the box, as long as they are installed.

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-tools.kdiff3.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"]
merge-tools.vimdiff.program = "vim"
merge-tools.vimdiff.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.

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. This is appropriate for most graphical merge tools.

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.

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 file content on standard input and repeat it, with any desired changes, on standard output. The file is only rewritten if the subprocess produces a successful exit code.

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.

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 $path substitution to provide the name of the file in a command argument.

[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"]

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. 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"]

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]
sign-all = true
backend = "gpg"
key = "4ED556E9729E000F"
## You can set `key` to anything accepted by `gpg -u`
# 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 ignore key expiry when verifying commit signatures. To consider expired keys as invalid you can set:

signing.backends.gpg.allow-expired-keys = false

SSH Signing

[signing]
sign-all = true
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"

Git settings

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"]'

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 local bookmark creation

When jj imports a new remote-tracking bookmark from Git, it can also create a local bookmark with the same name. This feature is disabled by default because it may be undesirable in some repositories, e.g.:

• There is a remote with a lot of historical bookmarks that you don't want to be exported to the co-located Git repo.
• There are multiple remotes with conflicting views of that bookmark, resulting in an unhelpful conflicted state.

You can enable this behavior by setting git.auto-local-bookmark like so,

git.auto-local-bookmark = true

This setting is applied only to new remote bookmarks. Existing remote bookmarks can be tracked individually by using jj bookmark track/untrack commands.

# import feature1 bookmark and start tracking it
jj bookmark track feature1@origin
# delete local gh-pages bookmark and stop tracking it
jj bookmark delete gh-pages
jj bookmark untrack gh-pages@upstream

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

Prefix for generated bookmarks on push

jj git push --change generates bookmark names with a prefix of "push-" by default. You can pick a different prefix by setting git.push-bookmark-prefix. For example:

git.push-bookmark-prefix = "martinvonz/push-"

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.

# Prevent pushing work in progress or anything explicitly labeled "private"
git.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.

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 core.fsmonitor option. Currently, the valid values are "none" or "watchman".

Watchman

To configure the Watchman filesystem monitor, set core.fsmonitor = "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 filestem changes by setting core.watchman.register_snapshot_trigger = true.

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

Snapshot settings

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
snapshot.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.

Ways to specify jj config: details

User config file

An easy way to find the user config file is:

jj config path --user

The rest of this section covers the details of where this file can be located.

On all platforms, the user's global jj configuration file is located at either ~/.jjconfig.toml (where ~ represents $HOME on Unix-likes, or %USERPROFILE% on Windows) or in a platform-specific directory. The platform-specific location is recommended for better integration with platform services. It is an error for both of these files to exist.

Platform	Value	Example
Linux	$XDG_CONFIG_HOME/jj/config.toml	/home/alice/.config/jj/config.toml
macOS	$HOME/Library/Application Support/jj/config.toml	/Users/Alice/Library/Application Support/jj/config.toml
Windows	{FOLDERID_RoamingAppData}\jj\config.toml	C:\Users\Alice\AppData\Roaming\jj\config.toml

The location of the jj config file can also be overridden with the JJ_CONFIG environment variable. If it is not empty, it should contain the path to a TOML file that will be used instead of any configuration file in the default locations. For example,

env JJ_CONFIG=/dev/null jj log       # Ignores any settings specified in the config file.

Specifying config on the command-line

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

jj --config-toml='ui.color="always"' --config-toml='ui.diff-editor="kdiff3"' split

Config specified this way must be valid TOML. In particular, string values must be surrounded by quotes. To pass these quotes to jj, most shells require surrounding those quotes with single quotes as shown above.

In sh-compatible shells, --config-toml can be used to merge entire TOML files with the config specified in .jjconfig.toml:

jj --config-toml="$(cat extra-config.toml)" log