Build drivers

Build drivers are configurations for how and where the BuildKit backend runs. Driver settings are customizable and allows fine-grained control of the builder. Buildx supports the following drivers:

  • docker: uses the BuildKit library bundled into the Docker daemon.
  • docker-container: creates a dedicated BuildKit container using Docker.
  • kubernetes: creates BuildKit pods in a Kubernetes cluster.
  • remote: connects directly to a manually managed BuildKit daemon.

Different drivers support different use cases. The default docker driver prioritizes simplicity and ease of use. It has limited support for advanced features like caching and output formats, and isn't configurable. Other drivers provide more flexibility and are better at handling advanced scenarios.

The following table outlines some differences between drivers.

Feature docker docker-container kubernetes remote
Automatically load image
Cache export ✓*
Tarball output
Multi-arch images
BuildKit configuration Managed externally

* The docker driver doesn't support all cache export options. See Cache storage backends for more information.

Loading to local image store

Unlike when using the default docker driver, images built using other drivers aren't automatically loaded into the local image store. If you don't specify an output, the build result is exported to the build cache only.

To build an image using a non-default driver and load it to the image store, use the --load flag with the build command:

$ docker buildx build --load -t <image> --builder=container .
...
=> exporting to oci image format                                                                                                      7.7s
=> => exporting layers                                                                                                                4.9s
=> => exporting manifest sha256:4e4ca161fa338be2c303445411900ebbc5fc086153a0b846ac12996960b479d3                                      0.0s
=> => exporting config sha256:adf3eec768a14b6e183a1010cb96d91155a82fd722a1091440c88f3747f1f53f                                        0.0s
=> => sending tarball                                                                                                                 2.8s
=> importing to docker

With this option, the image is available in the image store after the build finishes:

$ docker image ls
REPOSITORY                       TAG               IMAGE ID       CREATED             SIZE
<image>                          latest            adf3eec768a1   2 minutes ago       197MB

Load by default

Introduced in Buildx version 0.14.0

You can configure the custom build drivers to behave in a similar way to the default docker driver, and load images to the local image store by default. To do so, set the default-load driver option when creating the builder:

$ docker buildx create --driver-opt default-load=true

Note that, just like with the docker driver, if you specify a different output format with --output, the result will not be loaded to the image store unless you also explicitly specify --output type=docker or use the --load flag.

What's next

Read about each driver: