A few months ago, I published a post on Multi-platform Docker images with GoReleaser and GitHub Actions. Today’s post has the same idea, but using Podman instead of Docker.
The main advantage of Podman is that you can run in rootless mode (e.g. inside a container) and that it doesn’t require a daemon.
An example project
I created an example project showing with all the code needed for everything to work. You can check it out here.
A simple main.go
For our example, we’ll have a very simple main.go
file:
// main.go
package main
import (
"fmt"
"runtime"
)
var version = "dev"
func main() {
fmt.Println("example", version, runtime.GOOS, runtime.GOARCH)
}
A Dockerfile
GoReleaser builds Docker images by copying the previously built binaries to the images (instead of building the binary inside Docker itself). This guarantees that the binary inside the image and the one you download from the releases page is the same.
Our very basic Dockerfile
looks like this:
# Dockerfile
FROM alpine
COPY goreleaser-podman-actions-example /usr/bin/goreleaser-podman-actions-example
ENTRYPOINT ["/usr/bin/goreleaser-podman-actions-example"]
To account for multiple platforms, we either create several dockerfiles
, or use the --platform
build flag. We’ll use the second approach in our example.
We can test it without GoReleaser by running:
GOOS=linux GOARCH=amd64 go build .
podman build -t testimage:amd64 . --platform=linux/amd64
GOOS=linux GOARCH=arm64 go build .
podman build -t testimage:arm64v8 . --platform=linux/arm64/v8
With that in place, let’s check our GoReleaser config file.
The .goreleaser.yml
file
Our GoReleaser config file is very simple:
- One item in the
builds
section which will build for multiple platforms; - Two items in the
dockers
section, building one image foramd64
and another forarm64
, setting theuse
property topodman
; - One item in the new
docker_manifests
section, tying together the two images in a single manifest and also setting theuse
property topodman
.
It looks like this:
# .goreleaser.yml
builds:
- env: [CGO_ENABLED=0]
goos:
- linux
- darwin
- windows
goarch:
- amd64
- arm64
dockers:
- image_templates: ["ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-amd64"]
dockerfile: Dockerfile
use: podman
build_flag_templates:
- --platform=linux/amd64
- --label=org.opencontainers.image.title={{ .ProjectName }}
- --label=org.opencontainers.image.description={{ .ProjectName }}
- --label=org.opencontainers.image.url=https://github.com/caarlos0/{{ .ProjectName }}
- --label=org.opencontainers.image.source=https://github.com/caarlos0/{{ .ProjectName }}
- --label=org.opencontainers.image.version={{ .Version }}
- --label=org.opencontainers.image.created={{ time "2006-01-02T15:04:05Z07:00" }}
- --label=org.opencontainers.image.revision={{ .FullCommit }}
- --label=org.opencontainers.image.licenses=MIT
- image_templates: ["ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-arm64v8"]
goarch: arm64
dockerfile: Dockerfile
use: podman
build_flag_templates:
- --platform=linux/arm64/v8
- --label=org.opencontainers.image.title={{ .ProjectName }}
- --label=org.opencontainers.image.description={{ .ProjectName }}
- --label=org.opencontainers.image.url=https://github.com/caarlos0/{{ .ProjectName }}
- --label=org.opencontainers.image.source=https://github.com/caarlos0/{{ .ProjectName }}
- --label=org.opencontainers.image.version={{ .Version }}
- --label=org.opencontainers.image.created={{ time "2006-01-02T15:04:05Z07:00" }}
- --label=org.opencontainers.image.revision={{ .FullCommit }}
- --label=org.opencontainers.image.licenses=MIT
docker_manifests:
- name_template: ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}
use: podman
image_templates:
- ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-amd64
- ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-arm64v8
- name_template: ghcr.io/caarlos0/{{ .ProjectName }}:latest
use: podman
image_templates:
- ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-amd64
- ghcr.io/caarlos0/{{ .ProjectName }}:{{ .Version }}-arm64v8
You can check more options for builds, docker and docker manifests on GoReleaser’s website.
The labels added to the images are optional, but in the specific case of
ghcr.io
, they allows GitHub to know which image is built from which repository and other metadata.
We can now verify this locally with:
goreleaser release --snapshot --rm-dist
GoReleaser will use defaults for a lot of things, you can check the full config (with the defaults) in at dist/config.yaml
.
GitHub Actions
Here we pretty much copy what’s already in GitHub Actions section in the GoReleaser’s website:
# .github/workflows/goreleaser.yml
name: goreleaser
on:
push:
tags:
- '*'
permissions:
contents: write
jobs:
goreleaser:
runs-on: ubuntu-latest
steps:
- name: Checkout
uses: actions/checkout@v2
with:
fetch-depth: 0
- name: Set up QEMU
uses: docker/setup-qemu-action@v1
- name: Log in to ghcr.io
uses: redhat-actions/podman-login@v1
with:
username: ${{ github.repository_owner }}
password: ${{ secrets.GH_PAT }}
registry: ghcr.io
- name: Set up Go
uses: actions/setup-go@v2
with:
go-version: 1.16
- name: Run GoReleaser
uses: goreleaser/goreleaser-action@v2
with:
distribution: goreleaser-pro
version: latest
args: release --rm-dist
env:
GITHUB_TOKEN: ${{ secrets.GH_PAT }}
GORELEASER_KEY: ${{ secrets.GORELEASER_KEY }}
Important things to notice
- We need to setup
qemu
in order to build Docker images in platforms other thanlinux/amd64
usingpodman build
; - We need to login into the GitHub Container Registry with a Personal Access Token (PAT), since the default
GITHUB_TOKEN
does not have enough permissions; - Podman is GoReleaser Pro feature, so we need to use its distribution and pass a valid
GORELEASER_KEY
.
And that’s pretty much it!
Releasing
Now, we just need to push a tag, sit back, relax and watch the GoReleaser Action do everything.
In the end, you should have a release more or less like this:

GitHub Release - the changelog, assets and our multi-platform Docker image
You should also be able to see that the image is in fact multi-platform in the container registry:

GitHub Container Registry showing both OS/Arch combinations we provided.
We can now run our image with either Docker or Podman:
$ docker run --rm --platform linux/amd64 \
ghcr.io/caarlos0/goreleaser-podman-actions-example
example 0.0.1 linux amd64
$ podman run --rm --platform linux/amd64 \
ghcr.io/caarlos0/goreleaser-podman-actions-example
example 0.0.1 linux amd64
We can also test the arm64 image:
$ docker run --rm --platform linux/arm64 \
ghcr.io/caarlos0/goreleaser-podman-actions-example
example 0.0.1 linux arm64
$ podman run --rm --platform linux/arm64 \
ghcr.io/caarlos0/goreleaser-podman-actions-example
example 0.0.1 linux arm64
It works! 🎉
That’s it!
That’s it! I hope this is useful somehow.
Don’t forget to check out GoReleaser’s documentation for more details. Also make sure to take a look at Docker’s manifest documentation.
Also check out the GoReleaser Pro offering!