Build Images with BuildKit

Using BuildKit as build tool allows you to build images either locally or inside your Kubernetes cluster without a Docker daemon.

info

In order to use the build kit you'll either need to have Docker installed locally or alternatively the buildx CLI. If you only want to use the in-cluster build functionality, you won't need a running Docker daemon and just need the CLI tools instead.

When the buildKit field is defined for an image, DevSpace will use docker buildx build for building. If in-cluster building is enabled, DevSpace will deploy a BuildKit deployment into the Kubernetes cluster that will function as target BuildKit daemon for docker buildx build. You can also share a single Kubernetes BuildKit daemon across multiple users to share a common build cache.

To set buildKit as default build tool, use the following configuration:

images:
  backend:
    image: john/appbackend
    buildKit: {}

Custom Build Command

DevSpace provides two options to customize the BuildKit build command invocation:

command

The option takes a string array as value. By default, DevSpace will use docker buildx as base command for interacting with BuildKit, if this option is set, you can tell DevSpace to use a different base command. For example:

images:
  backend:
    image: john/appbackend
    buildKit: 
      command: ["/path/to/my/buildx"]

Explanation:

• buildKit tells DevSpace to use the BuildKit engine to build the image.
• The command option will tell DevSpace to use this command instead of docker buildx and the actual build command will look like this: /path/to/my/buildx build --tag john/appbackend:DRLzYNS --push --file Dockerfile --cache-to user/app:cache -

args

This option takes a string array as value. The arguments will be appended to the docker buildx build call DevSpace will run. For example:

images:
  backend:
    image: john/appbackend
    buildKit: 
      args: ["--cache-to", "user/app:cache"]

Explanation:

• buildKit tells DevSpace to use the BuildKit engine to build the image.
• The args option will append arguments to the docker buildx build command which will then look something like this: docker buildx build --tag john/appbackend:DRLzYNS --push --file Dockerfile --cache-to user/app:cache -

BuildKit Daemon

DevSpace can build images with a local Docker daemon or with a BuildKit instance deployed to a Kubernetes cluster.

Local Daemon

If in-cluster building is not explicitly enabled, DevSpace checks if a local Docker daemon is available for building images.

Minikube Docker Daemon

DevSpace preferably uses the Docker daemon running in the virtual machine that belongs to your local Kubernetes cluster instead of your regular Docker daemon. This has the advantage that images do not need to be pushed to a registry because Kubernetes can simply use the images available in the Docker daemon belonging to the kubelet of the local cluster. Using this method is only possible when your current kube-context points to a local Kubernetes cluster and is named minikube, docker-desktop or docker-for-desktop.

In-Cluster Deamon

If the inCluster field is defined for an image, DevSpace will build the image directly in the Kubernetes cluster instead of using the local Docker daemon. DevSpace will start or reuse a BuildKit deployment in the Kubernetes cluster that acts as target BuildKit daemon. For example:

images:
  backend:
    image: john/appbackend
    buildKit:
      inCluster: {}

Explanation:

• buildKit tells DevSpace to use the BuildKit engine to build the image.
• buildKit.inCluster tells DevSpace to build the image inside the target Kubernetes cluster instead of using the local docker daemon.
• By default, DevSpace will create a BuildKit daemon deployment inside the target namespace that will be used for this and all future builds.

DevSpace provides a set of config fields to customize the deployment of an in-cluster BuildKit daemon:

inCluster required

InCluster if specified, DevSpace will use BuildKit to build the image within the cluster

name required string

Name is the name of the builder to use. If omitted, DevSpace will try to create or reuse a builder in the form devspace-$NAMESPACE

namespace required string

Namespace where to create the builder deployment in. Defaults to the current active namespace.

rootless required boolean false

Rootless if enabled will create a rootless builder deployment.

image required string

Image is the docker image to use for the BuildKit deployment

nodeSelector required string

NodeSelector is the node selector to use for the BuildKit deployment

noCreate required boolean false

NoCreate. By default, DevSpace will try to create a new builder if it cannot be found. If this is true, DevSpace will fail if the specified builder cannot be found.

noRecreate required boolean false

NoRecreate. By default, DevSpace will try to recreate the builder if the builder configuration in the devspace.yaml differs from the actual builder configuration. If this is true, DevSpace will not try to do that.

noLoad required boolean false

NoLoad if enabled, DevSpace will not try to load the built image into the local docker daemon if skip push is defined

createArgs required string[]

CreateArgs are additional args to create the builder with.

Config Reference

buildKit required

BuildKit if buildKit is specified, DevSpace will build the image either in-cluster or locally with BuildKit

inCluster required

InCluster if specified, DevSpace will use BuildKit to build the image within the cluster

name required string

Name is the name of the builder to use. If omitted, DevSpace will try to create or reuse a builder in the form devspace-$NAMESPACE

namespace required string

Namespace where to create the builder deployment in. Defaults to the current active namespace.

rootless required boolean false

Rootless if enabled will create a rootless builder deployment.

image required string

Image is the docker image to use for the BuildKit deployment

nodeSelector required string

NodeSelector is the node selector to use for the BuildKit deployment

noCreate required boolean false

NoCreate. By default, DevSpace will try to create a new builder if it cannot be found. If this is true, DevSpace will fail if the specified builder cannot be found.

noRecreate required boolean false

NoRecreate. By default, DevSpace will try to recreate the builder if the builder configuration in the devspace.yaml differs from the actual builder configuration. If this is true, DevSpace will not try to do that.

noLoad required boolean false

NoLoad if enabled, DevSpace will not try to load the built image into the local docker daemon if skip push is defined

createArgs required string[]

CreateArgs are additional args to create the builder with.

preferMinikube required boolean false

PreferMinikube if false, will not try to use the minikube docker daemon to build the image

args required string[]

Args are additional arguments to call docker buildx build with

command required string[]

Command to override the base command to create a builder and build images. Defaults to ["docker", "buildx"]