jnc exec

Runs a command in a temporary, isolated environment. The required packages are automatically installed into a cached environment and the command is executed within it. This is useful for one-off commands without creating a full workspace. Temporary environments are cached for reuse. Clear them with jnc clean cache --exec.

Usage

jnc exec [OPTIONS] <COMMAND> [ARGS]...

Alias: x

Arguments

Argument	Description
`<COMMAND> [ARGS]...`	The executable to run, followed by any arguments. If `--spec` is not provided, the package is guessed from the command name.

Options

Option	Short	Description
`--spec <SPEC>`	`-s`	Matchspecs of packages to install. Can be specified multiple times. When provided, disables automatic package guessing.
`--with <SPEC>`	`-w`	Additional matchspecs to install alongside the guessed package. Cannot be combined with `--spec`.
`--channel <CHANNEL>`	`-c`	The channel to search for packages. Can be specified multiple times. Defaults to `conda-forge`.
`--platform <PLATFORM>`	`-p`	The platform to create the environment for. Defaults to the current platform.
`--force-reinstall`		Always create a new environment, even if a cached one exists.
`--list[=REGEX]`		List packages in the environment before executing the command. Optionally filter by regex.
`--no-modify-ps1`		Disable modification of the PS1 prompt to indicate the temporary environment.

Examples

Run Python in a temporary environment:

jnc exec python

Run Python with a specific version:

jnc exec --spec "python=3.12" python -- -c "print('hello')"

Run a command with additional packages:

jnc exec --with numpy python -- -c "import numpy; print(numpy.__version__)"

Use a specific channel:

jnc exec --channel conda-forge --spec "nodejs=20" node -- --version

Force a fresh environment:

jnc exec --force-reinstall python

List packages in the temporary environment before running:

jnc exec --list python

Overview

Commands

jnc exec

jnc exec

Usage

Arguments

Options

Examples

​jnc exec

​Usage

​Arguments

​Options

​Examples

jnc exec

Usage

Arguments

Options

Examples