Using the new prebuilt builder on GoReleaser

You can now import pre-built binaries into GoReleaser!

This feature was made with mainly two cases in mind:

1. You are migrating to GoReleaser and already have the build part covered by a Makefile or some other tool, and you don’t want to change that
2. You want to build each platform on a different machine and join the binaries later (for performance or CGO reasons)

Let’s talk about them.

1. Another builder

In this case, you’ll likely have a Makefile or some other tool doing the heavy lifting of building everything for you already.

In that case, you can simply use something like the following as your build config for GoReleaser:

# .goreleaser.yml
builds:
-
  # Set the builder to prebuilt
  builder: prebuilt

  # Specify the goos/goarch/goarm/gomips you want:
  goos: [linux, darwin]
  goarch: [amd64, arm64]

  prebuilt:
    # Set the path template of where to look for the binaries
    path: ./tmp/mybin_{{ .Os }}_{{ .Arch }}

# archive, package, sign, etc

This will make GoReleaser try to import into its release cycle the following binaries:

• ./tmp/mybin_linux_amd64
• ./tmp/mybin_linux_arm64
• ./tmp/mybin_darwin_amd64
• ./tmp/mybin_darwin_armd64

The only check GoReleaser will do is if these files are readable. If so, it will proceed as if they were built by GoReleaser itself.

PS: it is important that the folder in which your pre-built binaries are is either outside the repository or in your .gitignore.

2. Split builds in several machines

You might want to this to speed up/parallelize the build process, or maybe because of CGO.

Whatever your case may be, you can still use GoReleaser to build the binaries by having 2 or more GoReleaser config files, for example:

# .builds.goreleaser.yml
dist: tmp
builds:
-
  goos: [linux, darwin]
  goarch: [amd64, arm64]
	# flags, envs, etc

You can then build each by running something like on each machine:

goreleaser build --single-target -f .builds.goreleaser.yml

Then, you can copy all the built binares into the tmp folder, and import those binaries using a config like this:

# .goreleaser.yml
builds:
-
  # Set the builder to prebuilt
  builder: prebuilt

  # Specify the goos/goarch/goarm/gomips you want:
  goos: [linux, darwin]
  goarch: [amd64, arm64]

  prebuilt:
    # Set the path template of where to look for the binaries
    path: ./tmp/mybin_{{ .Os }}_{{ .Arch }}

# archive, package, sign, etc

And GoReleaser will proceed as usual.

PS: it is important that the folder in which your pre-built binaries are is either outside the repository or in your .gitignore.

This is a new feature

This feature just landed in GoReleaser Pro v0.179.0, which was released today!

Here’s the documentation for this feature: link.

If you want to test this feature, here’s a limited seats discount link since you read this entire article 🤘

Cheers! ✌️