Dev Packages

The source packages in the [dev] table are not built or installed into the pixi environment. The build-dependencies, host-dependencies and run-dependencies of those packages are installed into the pixi environment.

Source dependencies in the [dependencies] section are build in an isolated environment and then installed into the workspace. This means that the build- and host-dependencies will not be in the pixi environment.

This document explains how you can use the [dev] table to depend on the development dependencies of a package.

Using the [dev] table

Assume a Rust package that you want to develop using Pixi. Then we add a pixi.toml manifest file:

pixi.toml

[workspace]
channels = ["https://prefix.dev/conda-forge"]
platforms = ["linux-64", "win-64", "osx-64", "osx-arm64"]
preview = ['pixi-build']

[package.build.backend]
name = "pixi-build-rust"
version = "0.4.*"

Now you can use Pixi to build the package into a conda package:

pixi build

But because of the isolated build environments, the development dependencies such as cargo are not available in pixi run.

To change that you can add [dev] table to the manifest file:

pixi.toml

[dev]
dev-package = { path = "." }

Now when you run pixi install the development dependencies will be installed into the pixi environment. This means that you can now use cargo in pixi run:

pixi run cargo run

This is because the packages in the [dev] table are not build or installed but all their build-, host-, run-dependencies are. Thus, you can use them during development.

Extended example

This is a full pixi.toml example using the [dev] table:

pixi.toml

[workspace]
channels = ["https://prefix.dev/conda-forge"]
platforms = ["linux-64", "win-64", "osx-64", "osx-arm64"]
preview = ['pixi-build']

[package.build.backend]
name = "pixi-build-rust"
version = "0.4.*"

[package.build-dependencies]
cmake = "*"

[package.host-dependencies]
python = "*"

[package.run-dependencies]
bat = "*"

[dev]
dev-package = { path = "." }

[dependencies]
cargo-insta = "*"

[tasks]
build = "cargo build --release"
start = "cargo run"
test = "cargo test"

What you will see when you run pixi list is that you will have cmake, python, bat and rust installed all without defining them in the actual dependencies. This is because they are defined in the dependencies of the package that was included in the [dev] table.