nox1

General options:

These are general arguments used when invoking Nox.

-h, --help

Show this help message and exit.

--version

Show the Nox version and exit.

posargs

Arguments following ``--`` that are passed through to the session(s).

-f NOXFILE, --noxfile NOXFILE

Location of the Python file containing Nox sessions.

Sessions options:

These arguments are used to control which Nox session(s) to execute.

-l, --list-sessions, --list

List all available sessions and exit.

--json

JSON output formatting. Requires list-sessions currently.

-s [SESSIONS ...], -e [SESSIONS ...], --sessions [SESSIONS ...], --session [SESSIONS ...]

Which sessions to run. By default, all sessions will run.

-k KEYWORDS, --keywords KEYWORDS

Only run sessions that match the given expression.

-t [TAGS ...], --tags [TAGS ...]

Only run sessions with the given tags.

Python options:

These arguments are used to control which Python version(s) to use.

-p [PYTHONS ...], --pythons [PYTHONS ...], --python [PYTHONS ...]

Only run sessions that use the given python interpreter versions.

--extra-pythons [EXTRA_PYTHONS ...], --extra-python [EXTRA_PYTHONS ...]

Additionally, run sessions using the given python interpreter versions.

-P [FORCE_PYTHONS ...], --force-pythons [FORCE_PYTHONS ...], --force-python [FORCE_PYTHONS ...]

Run sessions with the given interpreters instead of those listed in the Noxfile. This is a shorthand for ``--python=X.Y --extra-python=X.Y``. It will also work on sessions that don't have any interpreter parametrized.

Environment options:

These arguments are used to control Nox's creation and usage of virtual environments.

-db {conda,mamba,micromamba,virtualenv,venv,uv,none}, --default-venv-backend {conda,mamba,micromamba,virtualenv,venv,uv,none}

Virtual environment backend to use by default for Nox sessions, this is ``'virtualenv'`` by default but any of ``['conda', 'mamba', 'micromamba', 'virtualenv', 'venv', 'uv', 'none']`` are accepted.

-fb {conda,mamba,micromamba,virtualenv,venv,uv,none}, --force-venv-backend {conda,mamba,micromamba,virtualenv,venv,uv,none}

Virtual environment backend to force-use for all Nox sessions in this run, overriding any other venv backend declared in the Noxfile and ignoring the default backend. Any of ``['conda', 'mamba', 'micromamba', 'virtualenv', 'venv', 'uv', 'none']`` are accepted.

--no-venv

Runs the selected sessions directly on the current interpreter, without creating a venv. This is an alias for '--force-venv-backend none'.

--reuse-venv {yes,no,always,never}

Controls existing virtualenvs recreation. This is ``'no'`` by default, but any of ``('yes', 'no', 'always', 'never')`` are accepted.

-r, --reuse-existing-virtualenvs

This is an alias for '--reuse-venv=yes|no'.

-N, --no-reuse-existing-virtualenvs

Disables --reuse-existing-virtualenvs if it is enabled in the Noxfile.

-R

Reuse existing virtualenvs and skip package reinstallation. This is an alias for '--reuse-existingvirtualenvs --no-install'.

--envdir ENVDIR

Directory where Nox will store virtualenvs, this is ``.nox`` by default.

Execution options:

These arguments are used to control execution of sessions.

-x, --stop-on-first-error

Stop after the first error.

--no-stop-on-first-error

Disables --stop-on-first-error if it is enabled in the Noxfile.

--error-on-missing-interpreters

Error instead of skipping sessions if an interpreter can not be located.

--no-error-on-missing-interpreters

Disables --error-on-missing-interpreters if it is enabled in the Noxfile.

--error-on-external-run

Error if run() is used to execute a program that isn't installed in a session's virtualenv.

--no-error-on-external-run

Disables --error-on-external-run if it is enabled in the Noxfile.

--install-only

Skip session.run invocations in the Noxfile.

--no-install

Skip invocations of session methods for installing packages (session.install, session.conda_install, session.run_install) when a virtualenv is being reused.

--non-interactive

Force session.interactive to always be False, even in interactive sessions.

Reporting options:

These arguments are used to control Nox's reporting during execution.

-v, --verbose

Logs the output of all commands run including commands marked silent.

-ts, --add-timestamp

Adds a timestamp to logged output.

--report REPORT

Output a report of all sessions to the given filename.

--nocolor, --no-color

Disable all color output.

--forcecolor, --force-color

Force color output, even if stdout is not an interactive terminal.