The configuration of pixi itself#

Apart from the project specific configuration pixi supports configuration options which are not required for the project to work but are local to the machine. The configuration is loaded in the following order:

LinuxmacOSWindows

Priority	Location	Comments
7	Command line arguments (`--tls-no-verify`, `--change-ps1=false`, etc.)	Configuration via command line arguments
6	`your_project/.pixi/config.toml`	Project-specific configuration
5	`$PIXI_HOME/config.toml`	Global configuration in `PIXI_HOME`.
4	`$HOME/.pixi/config.toml`	Global configuration in the user home directory.
3	`$XDG_CONFIG_HOME/pixi/config.toml`	XDG compliant user-specific configuration
2	`$HOME/.config/pixi/config.toml`	User-specific configuration
1	`/etc/pixi/config.toml`	System-wide configuration

Priority	Location	Comments
6	Command line arguments (`--tls-no-verify`, `--change-ps1=false`, etc.)	Configuration via command line arguments
5	`your_project/.pixi/config.toml`	Project-specific configuration
4	`$PIXI_HOME/config.toml`	Global configuration in `PIXI_HOME`.
3	`$HOME/.pixi/config.toml`	Global configuration in the user home directory.
2	`$HOME/Library/Application Support/pixi/config.toml`	User-specific configuration
1	`/etc/pixi/config.toml`	System-wide configuration

Priority	Location	Comments
6	Command line arguments (`--tls-no-verify`, `--change-ps1=false`, etc.)	Configuration via command line arguments
5	`your_project\.pixi\config.toml`	Project-specific configuration
4	`%PIXI_HOME%\config.toml`	Global configuration in `PIXI_HOME`.
3	`%USERPROFILE%\.pixi\config.toml`	Global configuration in the user home directory.
2	`%APPDATA%\pixi\config.toml`	User-specific configuration
1	`C:\ProgramData\pixi\config.toml`	System-wide configuration

Note

The highest priority wins. If a configuration file is found in a higher priority location, the values from the configuration read from lower priority locations are overwritten.

Note

To find the locations where pixi looks for configuration files, run pixi with -vv.

Configuration options#

Casing In Configuration

In versions of pixi 0.20.1 and older the global configuration used snake_case we've changed to kebab-case for consistency with the rest of the configuration. But we still support the old snake_case configuration, for older configuration options. These are:

default_channels
change_ps1
tls_no_verify
authentication_override_file
mirrors and sub-options
repodata-config and sub-options

The following reference describes all available configuration options.

`default-channels`#

The default channels to select when running pixi init or pixi global install. This defaults to only conda-forge.

config.toml

default-channels = ["conda-forge"]

Note

The default-channels are only used when initializing a new project. Once initialized the channels are used from the project manifest.

`change-ps1`#

When set to false, the (pixi) prefix in the shell prompt is removed. This applies to the pixi shell subcommand. You can override this from the CLI with --change-ps1.

config.toml

change-ps1 = true

`tls-no-verify`#

When set to true, the TLS certificates are not verified.

Warning

This is a security risk and should only be used for testing purposes or internal networks.

You can override this from the CLI with --tls-no-verify.

config.toml

tls-no-verify = false

`authentication-override-file`#

Override from where the authentication information is loaded. Usually, we try to use the keyring to load authentication data from, and only use a JSON file as a fallback. This option allows you to force the use of a JSON file. Read more in the authentication section.

config.toml

authentication-override-file = "/path/to/your/override.json"

`detached-environments`#

The directory where pixi stores the project environments, what would normally be placed in the .pixi/envs folder in a project's root. It doesn't affect the environments built for pixi global. The location of environments created for a pixi global installation can be controlled using the PIXI_HOME environment variable.

Warning

We recommend against using this because any environment created for a project is no longer placed in the same folder as the project. This creates a disconnect between the project and its environments and manual cleanup of the environments is required when deleting the project.

However, in some cases, this option can still be very useful, for instance to:

force the installation on a specific filesystem/drive.
install environments locally but keep the project on a network drive.
let a system-administrator have more control over all environments on a system.

This field can consist of two types of input.

A boolean value, true or false, which will enable or disable the feature respectively. (not "true" or "false", this is read as false)
A string value, which will be the absolute path to the directory where the environments will be stored.

config.toml

detached-environments = true

or:

config.toml

detached-environments = "/opt/pixi/envs"

The environments will be stored in the cache directory when this option is true. When you specify a custom path the environments will be stored in that directory.

The resulting directory structure will look like this:

/opt/pixi/envs
├── pixi-6837172896226367631
│   └── envs
└── NAME_OF_PROJECT-HASH_OF_ORIGINAL_PATH
    ├── envs # the runnable environments
    └── solve-group-envs # If there are solve groups

`pinning-strategy`#

The strategy to use for pinning dependencies when running pixi add. The default is semver but you can set the following:

no-pin: No pinning, resulting in an unconstraint dependency. *
semver: Pinning to the latest version that satisfies the semver constraint. Resulting in a pin to major for most versions and to minor for v0 versions.
exact-version: Pinning to the exact version, 1.2.3 -> ==1.2.3.
major: Pinning to the major version, 1.2.3 -> >=1.2.3, <2.
minor: Pinning to the minor version, 1.2.3 -> >=1.2.3, <1.3.
latest-up: Pinning to the latest version, 1.2.3 -> >=1.2.3.

config.toml

pinning-strategy = "no-pin"

`mirrors`#

Configuration for conda channel-mirrors, more info below.

config.toml

[mirrors]
# redirect all requests for conda-forge to the prefix.dev mirror
"https://conda.anaconda.org/conda-forge" = ["https://prefix.dev/conda-forge"]

# redirect all requests for bioconda to one of the three listed mirrors
# Note: for repodata we try the first mirror first.
"https://conda.anaconda.org/bioconda" = [
  "https://conda.anaconda.org/bioconda",
  # OCI registries are also supported
  "oci://ghcr.io/channel-mirrors/bioconda",
  "https://prefix.dev/bioconda",
]

`repodata-config`#

Configuration for repodata fetching.

config.toml

[repodata-config]
# disable fetching of jlap, bz2 or zstd repodata files.
# This should only be used for specific old versions of artifactory and other non-compliant
# servers.
disable-bzip2 = true   # don't try to download repodata.json.bz2
disable-jlap = true    # don't try to download repodata.jlap
disable-sharded = true # don't try to download sharded repodata
disable-zstd = true    # don't try to download repodata.json.zst

The above settings can be overridden on a per-channel basis by specifying a channel prefix in the configuration.

config.toml

[repodata-config."https://prefix.dev"]
disable-sharded = false

`pypi-config`#

To setup a certain number of defaults for the usage of PyPI registries. You can use the following configuration options:

index-url: The default index URL to use for PyPI packages. This will be added to a manifest file on a pixi init.
extra-index-urls: A list of additional URLs to use for PyPI packages. This will be added to a manifest file on a pixi init.
keyring-provider: Allows the use of the keyring python package to store and retrieve credentials.
allow-insecure-host: Allow insecure connections to host.

config.toml

[pypi-config]
# Main index url
index-url = "https://pypi.org/simple"
# list of additional urls
extra-index-urls = ["https://pypi.org/simple2"]
# can be "subprocess" or "disabled"
keyring-provider = "subprocess"
# allow insecure connections to host
allow-insecure-host = ["localhost:8080"]

index-url and extra-index-urls are not globals

Unlike pip, these settings, with the exception of keyring-provider will only modify the pixi.toml/pyproject.toml file and are not globally interpreted when not present in the manifest. This is because we want to keep the manifest file as complete and reproducible as possible.

`concurrency`#

Configure multiple settings to limit or extend the concurrency of pixi.

config.toml

[concurrency]
# The maximum number of concurrent downloads
# Defaults to 50 as that was found to be a good balance between speed and stability
downloads = 5

# The maximum number of concurrent dependency resolves
# Defaults to a heuristic based on the number of cores on the system
solves = 2

Set them through the CLI with:

pixi config set concurrency.solves 1
pixi config set concurrency.downloads 12

Experimental#

This allows the user to set specific experimental features that are not yet stable.

Please write a GitHub issue and add the flag experimental to the issue if you find issues with the feature you activated.

Caching environment activations#

Turn this feature on from configuration with the following command:

# For all your projects
pixi config set experimental.use-environment-activation-cache true --global

# For a specific project
pixi config set experimental.use-environment-activation-cache true --local

This will cache the environment activation in the .pixi/activation-env-v0 folder in the project root. It will create a json file for each environment that is activated, and it will be used to activate the environment in the future.

> tree .pixi/activation-env-v0/
.pixi/activation-env-v0/
├── activation_default.json
└── activation_lint.json

> cat  .pixi/activation-env-v0/activation_lint.json
{"hash":"8d8344e0751d377a","environment_variables":{<ENVIRONMENT_VARIABLES_USED_IN_ACTIVATION>}}

The hash is a hash of the data on that environment in the pixi.lock, plus some important information on the environment activation. Like [activation.scripts] and [activation.env] from the manifest file.
The environment_variables are the environment variables that are set when activating the environment.

You can ignore the cache by running:

pixi run/shell/shell-hook --force-activate

Set the configuration with:

config.toml

[experimental]
# Enable the use of the environment activation cache
use-environment-activation-cache = true

Why is this experimental?

This feature is experimental because the cache invalidation is very tricky, and we don't want to disturb users that are not affected by activation times.

Mirror configuration#

You can configure mirrors for conda channels. We expect that mirrors are exact copies of the original channel. The implementation will look for the mirror key (a URL) in the mirrors section of the configuration file and replace the original URL with the mirror URL.

To also include the original URL, you have to repeat it in the list of mirrors.

The mirrors are prioritized based on the order of the list. We attempt to fetch the repodata (the most important file) from the first mirror in the list. The repodata contains all the SHA256 hashes of the individual packages, so it is important to get this file from a trusted source.

You can also specify mirrors for an entire "host", e.g.

config.toml

[mirrors]
"https://conda.anaconda.org" = ["https://prefix.dev/"]

This will forward all request to channels on anaconda.org to prefix.dev. Channels that are not currently mirrored on prefix.dev will fail in the above example.

OCI Mirrors#

You can also specify mirrors on the OCI registry. There is a public mirror on the Github container registry (ghcr.io) that is maintained by the conda-forge team. You can use it like this:

config.toml

[mirrors]
"https://conda.anaconda.org/conda-forge" = [
  "oci://ghcr.io/channel-mirrors/conda-forge",
]

The GHCR mirror also contains bioconda packages. You can search the available packages on Github.

The configuration of pixi itself#

Configuration options#

default-channels#

change-ps1#

tls-no-verify#

authentication-override-file#

detached-environments#

pinning-strategy#

mirrors#

repodata-config#

pypi-config#

concurrency#

Experimental#

Caching environment activations#

Mirror configuration#

OCI Mirrors#

`default-channels`#

`change-ps1`#

`tls-no-verify`#

`authentication-override-file`#

`detached-environments`#

`pinning-strategy`#

`mirrors`#

`repodata-config`#

`pypi-config`#

`concurrency`#