compression=zstd

[mustafa0x]

How can I use zstd compression? Uploading is quite slow. And research indicated that compressing with zstd at build time would improve.

This didn't work

builder:
  arch: arm64
  driver: docker
  compression: zstd
  compression-level: 1

Edit: fixed; needs to be in cache:

[sjparkinson]

There isn't an option as far as I can see to configure zstd for the published image, only for the image cache.

As a workaround, I've edited the Kamal binstub at bin/kamal to include the following:

# PATCH: Kamal has no deploy.yml configuration to specify buildx output compression.
require "kamal"

Kamal::Commands::Builder::Base.prepend(Module.new do
  def push(export_action = "registry", tag_as_dirty: false, no_cache: false)
    export_action = "#{export_action},compression=zstd,compression-level=12,force-compression=true"
    super
  end
end)

load Gem.bin_path("kamal", "kamal")