Bringing pixi to production

You can bring pixi projects into production by either containerizing it using tools like Docker or by using quantco/pixi-pack.

@pavelzw from QuantCo wrote a blog post about bringing pixi to production. You can read it here.

Docker

We provide a simple docker image at pixi-docker that contains the pixi executable on top of different base images.

The images are available on ghcr.io/prefix-dev/pixi.

There are different tags for different base images available:

• latest - based on ubuntu:jammy
• focal - based on ubuntu:focal
• bullseye - based on debian:bullseye
• jammy-cuda-12.2.2 - based on nvidia/cuda:12.2.2-jammy
• ... and more

All tags

For all tags, take a look at the build script.

Example usage

The following example uses the pixi docker image as a base image for a multi-stage build. It also makes use of pixi shell-hook to not rely on pixi being installed in the production container.

More examples

For more examples, take a look at pavelzw/pixi-docker-example.

FROM ghcr.io/prefix-dev/pixi:0.39.3 AS build

# copy source code, pixi.toml and pixi.lock to the container
WORKDIR /app
COPY . .
# install dependencies to `/app/.pixi/envs/prod`
# use `--locked` to ensure the lockfile is up to date with pixi.toml
RUN pixi install --locked -e prod
# create the shell-hook bash script to activate the environment
RUN pixi shell-hook -e prod -s bash > /shell-hook
RUN echo "#!/bin/bash" > /app/entrypoint.sh
RUN cat /shell-hook >> /app/entrypoint.sh
# extend the shell-hook script to run the command passed to the container
RUN echo 'exec "$@"' >> /app/entrypoint.sh

FROM ubuntu:24.04 AS production
WORKDIR /app
# only copy the production environment into prod container
# please note that the "prefix" (path) needs to stay the same as in the build container
COPY --from=build /app/.pixi/envs/prod /app/.pixi/envs/prod
COPY --from=build --chmod=0755 /app/entrypoint.sh /app/entrypoint.sh
# copy your project code into the container as well
COPY ./my_project /app/my_project

EXPOSE 8000
ENTRYPOINT [ "/app/entrypoint.sh" ]
# run your app inside the pixi environment
CMD [ "uvicorn", "my_project:app", "--host", "0.0.0.0" ]

pixi-pack

pixi-pack is a simple tool that takes a pixi environment and packs it into a compressed archive that can be shipped to the target machine.

It can be installed via

pixi global install pixi-pack

Or by downloading our pre-built binaries from the releases page.

Instead of installing pixi-pack globally, you can also use pixi exec to run pixi-pack in a temporary environment:

pixi exec pixi-pack pack
pixi exec pixi-pack unpack environment.tar

You can pack an environment with

pixi-pack pack --manifest-file pixi.toml --environment prod --platform linux-64

This will create a environment.tar file that contains all conda packages required to create the environment.

# environment.tar
| pixi-pack.json
| environment.yml
| channel
|    ├── noarch
|    |    ├── tzdata-2024a-h0c530f3_0.conda
|    |    ├── ...
|    |    └── repodata.json
|    └── linux-64
|         ├── ca-certificates-2024.2.2-hbcca054_0.conda
|         ├── ...
|         └── repodata.json

Unpacking an environment

With pixi-pack unpack environment.tar, you can unpack the environment on your target system. This will create a new conda environment in ./env that contains all packages specified in your pixi.toml. It also creates an activate.sh (or activate.bat on Windows) file that lets you activate the environment without needing to have conda or micromamba installed.

Cross-platform packs

Since pixi-pack just downloads the .conda and .tar.bz2 files from the conda repositories, you can trivially create packs for different platforms.

pixi-pack pack --platform win-64

You can only unpack a pack on a system that has the same platform as the pack was created for.

Inject additional packages

You can inject additional packages into the environment that are not specified in pixi.lock by using the --inject flag:

pixi-pack pack --inject local-package-1.0.0-hbefa133_0.conda --manifest-pack pixi.toml

This can be particularly useful if you build the project itself and want to include the built package in the environment but still want to use pixi.lock from the project.

Unpacking without pixi-pack

If you don't have pixi-pack available on your target system, you can still install the environment if you have conda or micromamba available. Just unarchive the environment.tar, then you have a local channel on your system where all necessary packages are available. Next to this local channel, you will find an environment.yml file that contains the environment specification. You can then install the environment using conda or micromamba:

tar -xvf environment.tar
micromamba create -p ./env --file environment.yml
# or
conda env create -p ./env --file environment.yml

The environment.yml and repodata.json files are only for this use case, pixi-pack unpack does not use them.