conda backend

The conda backend installs command-line packages and their dependencies from conda-forge or another conda channel. mise solves and downloads the packages itself, so you do not need conda, mamba or micromamba.

Requirements

Nothing beyond mise. The package must be built for your platform, or be a noarch package; mise picks the platform's conda subdirectory:

Platform	Conda subdir
Linux x64	linux-64
Linux ARM64	linux-aarch64
macOS x64	osx-64
macOS ARM64	osx-arm64
Windows x64	win-64

The solver also considers noarch packages. A noarch package can still depend on platform-specific packages, so it is not guaranteed to install on every host. Native requirements such as a compatible libc or GPU driver still come from the host.

Usage

Install FFmpeg in the current project and run it:

mise use conda:ffmpeg
mise exec -- ffmpeg -version

This writes the following to mise.toml. Add -g for your global config.

[tools]
"conda:ffmpeg" = "latest"

Run mise ls-remote conda:ffmpeg to list versions, and pin one with mise use conda:ffmpeg@8.1.2.

How commands run

Each package is installed into its own conda prefix with its dependencies. Only the requested package's commands reach your PATH; its dependencies' commands do not.

If the prefix needs activating (the package ships etc/conda/activate.d scripts, the prefix's bin directory holds executables from its dependencies, or one of its commands is a script), mise starts its commands through a launcher. The launcher sets CONDA_PREFIX, puts the prefix's executables ahead of your PATH, and runs the activation scripts. Programs the command starts inherit that PATH.

A single-binary package such as conda:ripgrep needs no activation, so on Unix mise symlinks its commands directly. They start without an extra shell process but do not see CONDA_PREFIX. On Windows every command goes through a launcher.

mise solves one package per tool in an isolated prefix. It does not read or maintain an environment.yml.

Mirrors

To fetch conda-forge or another channel through a mirror, map its URL with url_replacements. mise applies the replacements to channel metadata and package downloads, and refuses a replacement that would send credentials from an https:// URL to an http:// one.

Tool options

Set these on the tool's entry in [tools], or inline, as in 'conda:my-tool[channel=my-team]'. Options every backend accepts are described under tool options.

channel

Install one package from a channel other than conda.channel, which defaults to conda-forge:

[tools]
"conda:my-tool" = { version = "latest", channel = "my-team" }

The value can be a channel name on anaconda.org or a full channel URL, such as https://conda.example.com/my-team, for a private or mirrored conda server.

mise solves against that one channel, so the package and all of its dependencies must come from it. Channels that build on conda-forge, such as bioconda, usually cannot be used on their own for this reason.

Settings

Set these under [settings] in a config file, with mise settings set, or with a setting's environment variable where it has one. See which value wins when a setting is set in more than one place.

conda.channel

Channel for conda: tools that do not set their own.

• Type: string
• Default: "conda-forge"
• Environment variable: MISE_CONDA_CHANNEL

The package and all of its dependencies must come from this one channel. Override it for one tool with the channel tool option.

Troubleshooting

Symptom	What to check
Command not found	Check that the package itself provides that command. Commands from its dependencies are not put on your PATH.
Solving fails	Check that the package and every dependency exist in the selected channel for the platform named in the error.
Package is not available	It may not be built for your platform; look for your subdir in the package's files on anaconda.org.

Implementation: src/backend/conda.rs.