{ { % experimental \%}}

Bake is an experimental feature, and we are looking for feedback from users.

{ { % /experimental \%}}

Bake is a feature of Docker Buildx that lets you define your build configuraton using a declarative file, as opposed to specifying a complex CLI expression. It also lets you run multiple builds concurrently with a single invocation.

A Bake file can be written in HCL, JSON, or YAML formats, where the YAML format is an extension of a Docker Compose file. Here's an example Bake file in HCL format:

group "default" {
  targets = ["frontend", "backend"]
}

target "frontend" {
  context = "./frontend"
  dockerfile = "frontend.Dockerfile"
  args = {
    NODE_VERSION = "22"
  }
  tags = ["myapp/frontend:latest"]
}

target "backend" {
  context = "./backend"
  dockerfile = "backend.Dockerfile"
  args = {
    GO_VERSION = "\{\{\% param "example_go_version" \%\}\}"
  }
  tags = ["myapp/backend:latest"]
}

The group block defines a group of targets that can be built concurrently. Each target block defines a build target with its own configuration, such as the build context, Dockerfile, and tags.

To invoke a build using the above Bake file, you can run:

$ docker buildx bake

This executes the default group, which builds the frontend and backend targets concurrently.

Get started#

To learn how to get started with Bake, head over to the Bake introduction.