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title: "Configuration" sidebar_position: 4

Configuration

012 reads one settings file, in the style of Ghostty's:

OS	File
Linux, BSD	$XDG_CONFIG_HOME/012/config, usually ~/.config/012/config
macOS	~/Library/Application Support/012/config, or $XDG_CONFIG_HOME/012/config when that's set
Windows	%AppData%\012\config, or %XDG_CONFIG_HOME%\012\config when that's set

# ~/.config/012/config
theme = light:Builtin Solarized Light,dark:Dracula
chart-images = true
jev-api-key-command = op read op://Private/TypeSafe/credential
config-file = ?local.conf

• One key = value per line. # starts a comment line; blank lines are ignored. Quote a value (" like this ") to keep spaces at its ends.
• An empty value (theme =) puts an option back to its default.
• config-file = path reads another file after this one, relative to this file's directory; its settings win over the ones around it. A leading ? (config-file = ?local.conf) makes it optional. Includes can nest; a file that includes itself is skipped with a warning.
• Unknown keys, bad values and missing includes never stop 012: it starts with the defaults for those options and says what's wrong on the context line (and in 012 config).

Settings are process-wide. Settings that belong to a workbook, such as decimal arithmetic and its locale, are saved in the workbook's .012 file instead; locale here is the default for workbooks without one.

Precedence: command-line flags win over environment variables, which win over the config file, which wins over the defaults. 012 config shows where each value came from.

Secrets never go in this file. The JEV API key lives in the OS credential store or comes from a command; see JEV setup.

Commands

Command	Does
012 config	print the settings in effect, each with where it came from (file and line, variable, flag or default), secrets redacted, then any warnings
012 config path	print the config file's path
012 config edit	open the file in $VISUAL or $EDITOR, creating it with every option commented out if it doesn't exist
012 config default	print a config file with every option at its default, commented out and described
012 config themes	list the themes: built in and in the themes directory
012 config set-key	store the JEV API key in the credential store, read from the terminal without echo or from stdin
012 config delete-key	remove the JEV API key from the credential store

In the app, File > Settings has Theme (a picker with live preview), Open config file (in your editor, reloading when it closes), Reload config and JEV API key (stored, then checked with one test call: see JEV functions). Reloading applies the options marked "File > Settings > Reload config" below; the rest take effect on the next start.

Options

Option	Default	Environment, flag
theme	terminal	O12_THEME, --theme
chart-images	true	O12_CHART_IMAGES
notifications	true	O12_NOTIFICATIONS
keymap	default	O12_KEYMAP
locale	en-US	O12_LOCALE
max-cells	10000000	O12_MAX_CELLS
shell	ask	O12_SHELL
nu-timeout	30s	O12_NU_TIMEOUT
nu-config	false	O12_NU_CONFIG
nu-save-cell-kb	1024	O12_NU_SAVE_CELL_KB
nu-save-notebook-kb	8192	O12_NU_SAVE_NOTEBOOK_KB
jev-api-key-command
jev-credential-store	true	O12_JEV_CREDENTIAL_STORE
jev-base-url		TYPESAFE_BASE_URL
jev-model		TYPESAFE_DEFAULT_MODEL
log-file		O12_LOG, --log
log-level	info	O12_LOG_LEVEL
otlp-endpoint		OTEL_EXPORTER_OTLP_ENDPOINT, --otlp
serve-listen	127.0.0.1:2312
serve-authorized-keys	~/.ssh/authorized_keys
serve-host-key
serve-idle-timeout	30m
serve-max-sessions	8
serve-share	edit
serve-shell	false
config-file

Appearance

theme

Colors. terminal uses the terminal's own 16-color palette. high-contrast draws white on black or black on white by the terminal's background, with WCAG AAA contrast. Any other name is a terminal color scheme, built in (012 config themes lists them) or a file in the themes directory, drawn in its own colors with solid menu and status bars. light:NAME,dark:NAME picks one by the terminal's background and follows it when it changes.

Type	text
Default	terminal
Environment	O12_THEME
Flag	--theme
Applies	File > Settings > Reload config

chart-images

Draw charts as images on terminals with kitty graphics (kitty, Ghostty, WezTerm) or, outside tmux, sixel graphics (foot, xterm, mlterm, Windows Terminal). When false, charts are always text.

Type	true or false
Default	true
Environment	O12_CHART_IMAGES
Applies	File > Settings > Reload config

notifications

Send a desktop notification (OSC 9) when JEV answers or an import finishes while the terminal window is in the background.

Type	true or false
Default	true
Environment	O12_NOTIFICATIONS
Applies	File > Settings > Reload config

keymap

Keys in the grid. default works like Google Sheets; vim adds hjkl, counts, operators, visual selection and a : command line (File > Settings > Vim keys).

Type	one of default, vim
Default	default
Environment	O12_KEYMAP
Applies	File > Settings > Reload config

Data

locale

How new sheets and files without a locale of their own are typed and shown: decimal and thousands separators, date order, the currency symbol and the formula argument separator (; where the decimal separator is a comma), as in Sheets' File > Settings > Locale, which sets a file's own. Files store the same thing in every locale. When unset, the POSIX locale (LC_ALL, LC_NUMERIC, then LANG, e.g. de_DE.UTF-8) picks it if it's one of these.

Type	one of en-US, en-GB, en-CA, en-AU, de-DE, de-CH, fr-FR, fr-CA, es-ES, es-MX, it-IT, pt-BR, pt-PT, nl-NL, sv-SE, da-DK, nb-NO, fi-FI, pl-PL, cs-CZ, ru-RU, tr-TR, ja-JP, zh-CN
Default	en-US
Environment	O12_LOCALE
When unset	LC_ALL, LC_NUMERIC, LANG
Applies	File > Settings > Reload config

max-cells

The most cells an import keeps, and a paste or fill writes at once. Numbers and text take 20 to 60 bytes a cell and formulas about 750, so the default of ten million cells of data is 200 to 600 MB. Imports keep whole rows up to the budget and say how many they left out; larger pastes and fills are refused. A function that holds what it reads (SORT, TEXTJOIN) is given no more of a linked source. The grid itself is 1,048,576 rows by 16,384 columns (A to XFD) whatever this is.

Type	number
Default	10000000
Environment	O12_MAX_CELLS
Applies	File > Settings > Reload config

Nushell notebooks

shell

Whether notebooks run their code cells (docs/nushell/notebooks.md). ask runs what you write and asks once before running the cells of a file made on another computer; on never asks; off runs none. Opening a file never runs its cells.

Type	one of off, ask, on
Default	ask
Environment	O12_SHELL
Applies	File > Settings > Reload config

nu-timeout

Stop a notebook cell that runs longer than this; 0 lets it run until Stop (i i) stops it.

Type	duration
Default	30s
Environment	O12_NU_TIMEOUT
Applies	File > Settings > Reload config

nu-config

Run notebook cells with your nushell config files (config.nu, env.nu) rather than nu --no-config-file, for your own commands and aliases.

Type	true or false
Default	false
Environment	O12_NU_CONFIG
Applies	File > Settings > Reload config

nu-save-cell-kb

The largest output of one cell a saved file keeps, in kilobytes of NUON; a larger one is left out and shows not saved; run to see when the file is opened.

Type	number
Default	1024
Environment	O12_NU_SAVE_CELL_KB
Applies	File > Settings > Reload config

nu-save-notebook-kb

How much of all its cells' outputs a saved file keeps, in kilobytes of NUON: the outputs that fit, in the notebook's order.

Type	number
Default	8192
Environment	O12_NU_SAVE_NOTEBOOK_KB
Applies	File > Settings > Reload config

JEV functions

jev-api-key-command

A command that prints the TypeSafe API key, used when TYPESAFE_API_KEY isn't set and the credential store has no key, e.g. op read op://Private/TypeSafe/credential or pass show typesafe. It runs the first time a sheet asks JEV something, without a shell, for up to 10 seconds, and its first line of output is the key; for pipes, write sh -c '...' yourself. The key itself never goes in this file.

Type	command
Default	(empty)
Applies	restart 012

jev-credential-store

Look for the API key in the OS credential store (macOS Keychain, Windows Credential Manager, the Secret Service on Linux), where 012 config set-key and Settings put it.

Type	true or false
Default	true
Environment	O12_JEV_CREDENTIAL_STORE
Applies	restart 012

jev-base-url

The TypeSafe service to ask; the SDK's default when empty. Must be https, except on localhost.

Type	URL
Default	(empty)
Environment	TYPESAFE_BASE_URL
Applies	restart 012

jev-model

The JEV model to ask; the service's default when empty.

Type	text
Default	(empty)
Environment	TYPESAFE_DEFAULT_MODEL
Applies	restart 012

Telemetry

log-file

Append telemetry events to this JSON log file. See docs/contributing/observability.md.

Type	path
Default	(empty)
Environment	O12_LOG
Flag	--log
Applies	restart 012

log-level

The least severe telemetry event recorded; debug adds every frame and command.

Type	one of debug, info, warn, error
Default	info
Environment	O12_LOG_LEVEL
Applies	restart 012

otlp-endpoint

Send telemetry to this OTLP/HTTP collector, e.g. http://localhost:4318. The other OTEL_* variables still apply.

Type	URL
Default	(empty)
Environment	OTEL_EXPORTER_OTLP_ENDPOINT
Flag	--otlp
Applies	restart 012

012 serve

serve-listen

The address 012 serve listens on. Anything but the loopback address lets other machines reach it (with an authorized key). See docs/terminal/ssh.md.

Type	host:port
Default	127.0.0.1:2312
Applies	restart 012

serve-authorized-keys

The public keys allowed to log in to 012 serve, in OpenSSH's authorized_keys format.

Type	path
Default	~/.ssh/authorized_keys
Applies	restart 012

serve-host-key

012 serve's private host key, generated when missing; ssh_host_ed25519_key in the config directory when empty.

Type	path
Default	(empty)
Applies	restart 012

serve-idle-timeout

End a 012 serve session that has had no input for this long; 0 never does.

Type	duration
Default	30m
Applies	restart 012

serve-max-sessions

How many 012 serve sessions may run at once; more are turned away.

Type	number
Default	8
Applies	restart 012

serve-share

Whether 012 serve sessions opening the same file share its workbook: edit, everyone edits; view, one writes and the others follow until writing is handed over; off, each session has its own copy.

Type	one of edit, view, off
Default	edit
Applies	restart 012

serve-shell

Let 012 serve sessions run notebooks' code cells, as the user 012 serve runs as, following the shell option. Off, served notebooks show their cells and saved outputs but run nothing.

Type	true or false
Default	false
Applies	restart 012

Config files

config-file

Read another config file after this one, relative to this file's directory. A leading ? makes it optional: no warning when it doesn't exist.

Type	path
Default	(empty)
Repeatable	yes
Applies	restart 012