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How to enable Docker BuildKit in MacOS Docker Desktop

Since Docker 18.09, you can the BuildKit feature to take advantages of improved performance and extra features when building images — see Build images with BuildKit from the Docker docs.

MacOS users using Docker Desktop, can enable this be update the Docker daemon JSON config file to:

  "experimental": false,
  "debug": true,
  "features": {
    "buildkit": true

This is done via the Preferences > Docker Engine menu option in the GUI.

(This is accurate as of Docker Desktop v3.0.3)