docker-docs/data/buildx/docker_buildx_build.yaml

command: docker buildx build
aliases: docker buildx build, docker buildx b
short: Start a build
long: |-
    The `buildx build` command starts a build using BuildKit. This command is similar
    to the UI of `docker build` command and takes the same flags and arguments.

    For documentation on most of these flags, refer to the [`docker build`
    documentation](/engine/reference/commandline/image_build/).
    This page describes a subset of the new flags.
usage: docker buildx build [OPTIONS] PATH | URL | -
pname: docker buildx
plink: docker_buildx.yaml
options:
    - option: add-host
      value_type: stringSlice
      default_value: '[]'
      description: 'Add a custom host-to-IP mapping (format: `host:ip`)'
      details_url: /engine/reference/commandline/image_build/#add-host
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: allow
      value_type: stringSlice
      default_value: '[]'
      description: |
        Allow extra privileged entitlement (e.g., `network.host`, `security.insecure`)
      details_url: '#allow'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: annotation
      value_type: stringArray
      default_value: '[]'
      description: Add annotation to the image
      details_url: '#annotation'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: attest
      value_type: stringArray
      default_value: '[]'
      description: 'Attestation parameters (format: `type=sbom,generator=image`)'
      details_url: '#attest'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: build-arg
      value_type: stringArray
      default_value: '[]'
      description: Set build-time variables
      details_url: '#build-arg'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: build-context
      value_type: stringArray
      default_value: '[]'
      description: Additional build contexts (e.g., name=path)
      details_url: '#build-context'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cache-from
      value_type: stringArray
      default_value: '[]'
      description: |
        External cache sources (e.g., `user/app:cache`, `type=local,src=path/to/dir`)
      details_url: '#cache-from'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cache-to
      value_type: stringArray
      default_value: '[]'
      description: |
        Cache export destinations (e.g., `user/app:cache`, `type=local,dest=path/to/dir`)
      details_url: '#cache-to'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cgroup-parent
      value_type: string
      description: Set the parent cgroup for the `RUN` instructions during build
      details_url: /engine/reference/commandline/image_build/#cgroup-parent
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: compress
      value_type: bool
      default_value: "false"
      description: Compress the build context using gzip
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cpu-period
      value_type: int64
      default_value: "0"
      description: Limit the CPU CFS (Completely Fair Scheduler) period
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cpu-quota
      value_type: int64
      default_value: "0"
      description: Limit the CPU CFS (Completely Fair Scheduler) quota
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cpu-shares
      shorthand: c
      value_type: int64
      default_value: "0"
      description: CPU shares (relative weight)
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cpuset-cpus
      value_type: string
      description: CPUs in which to allow execution (`0-3`, `0,1`)
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: cpuset-mems
      value_type: string
      description: MEMs in which to allow execution (`0-3`, `0,1`)
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: detach
      value_type: bool
      default_value: "false"
      description: Detach buildx server (supported only on linux)
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: true
      kubernetes: false
      swarm: false
    - option: file
      shorthand: f
      value_type: string
      description: 'Name of the Dockerfile (default: `PATH/Dockerfile`)'
      details_url: /engine/reference/commandline/image_build/#file
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: force-rm
      value_type: bool
      default_value: "false"
      description: Always remove intermediate containers
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: iidfile
      value_type: string
      description: Write the image ID to the file
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: isolation
      value_type: string
      description: Container isolation technology
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: label
      value_type: stringArray
      default_value: '[]'
      description: Set metadata for an image
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: load
      value_type: bool
      default_value: "false"
      description: Shorthand for `--output=type=docker`
      details_url: '#load'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: memory
      shorthand: m
      value_type: string
      description: Memory limit
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: memory-swap
      value_type: string
      description: |
        Swap limit equal to memory plus swap: `-1` to enable unlimited swap
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: metadata-file
      value_type: string
      description: Write build result metadata to the file
      details_url: '#metadata-file'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: network
      value_type: string
      default_value: default
      description: Set the networking mode for the `RUN` instructions during build
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: no-cache
      value_type: bool
      default_value: "false"
      description: Do not use cache when building the image
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: no-cache-filter
      value_type: stringArray
      default_value: '[]'
      description: Do not cache specified stages
      details_url: '#no-cache-filter'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: output
      shorthand: o
      value_type: stringArray
      default_value: '[]'
      description: 'Output destination (format: `type=local,dest=path`)'
      details_url: '#output'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: platform
      value_type: stringArray
      default_value: '[]'
      description: Set target platform for build
      details_url: '#platform'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: print
      value_type: string
      description: Print result of information request (e.g., outline, targets)
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: true
      kubernetes: false
      swarm: false
    - option: progress
      value_type: string
      default_value: auto
      description: |
        Set type of progress output (`auto`, `plain`, `tty`). Use plain to show container output
      details_url: '#progress'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: provenance
      value_type: string
      description: Shorthand for `--attest=type=provenance`
      details_url: '#provenance'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: pull
      value_type: bool
      default_value: "false"
      description: Always attempt to pull all referenced images
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: push
      value_type: bool
      default_value: "false"
      description: Shorthand for `--output=type=registry`
      details_url: '#push'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: quiet
      shorthand: q
      value_type: bool
      default_value: "false"
      description: Suppress the build output and print image ID on success
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: rm
      value_type: bool
      default_value: "true"
      description: Remove intermediate containers after a successful build
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: root
      value_type: string
      description: Specify root directory of server to connect
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: true
      kubernetes: false
      swarm: false
    - option: sbom
      value_type: string
      description: Shorthand for `--attest=type=sbom`
      details_url: '#sbom'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: secret
      value_type: stringArray
      default_value: '[]'
      description: |
        Secret to expose to the build (format: `id=mysecret[,src=/local/secret]`)
      details_url: '#secret'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: security-opt
      value_type: stringSlice
      default_value: '[]'
      description: Security options
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: server-config
      value_type: string
      description: |
        Specify buildx server config file (used only when launching new server)
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: true
      kubernetes: false
      swarm: false
    - option: shm-size
      value_type: bytes
      default_value: "0"
      description: Size of `/dev/shm`
      details_url: '#shm-size'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: squash
      value_type: bool
      default_value: "false"
      description: Squash newly built layers into a single new layer
      deprecated: false
      hidden: true
      experimental: false
      experimentalcli: true
      kubernetes: false
      swarm: false
    - option: ssh
      value_type: stringArray
      default_value: '[]'
      description: |
        SSH agent socket or keys to expose to the build (format: `default|<id>[=<socket>|<key>[,<key>]]`)
      details_url: '#ssh'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: tag
      shorthand: t
      value_type: stringArray
      default_value: '[]'
      description: 'Name and optionally a tag (format: `name:tag`)'
      details_url: /engine/reference/commandline/image_build/#tag
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: target
      value_type: string
      description: Set the target build stage to build
      details_url: /engine/reference/commandline/image_build/#target
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
    - option: ulimit
      value_type: ulimit
      default_value: '[]'
      description: Ulimit options
      details_url: '#ulimit'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
inherited_options:
    - option: builder
      value_type: string
      description: Override the configured builder instance
      details_url: '#builder'
      deprecated: false
      hidden: false
      experimental: false
      experimentalcli: false
      kubernetes: false
      swarm: false
examples: |-
    ### Create annotations (--annotation) {#annotation}

    ```text
    --annotation="key=value"
    --annotation="[type:]key=value"
    ```

    Add OCI annotations to the image index, manifest, or descriptor.
    The following example adds the `foo=bar` annotation to the image manifests:

    ```console
    $ docker buildx build -t TAG --annotation "foo=bar" --push .
    ```

    You can optionally add a type prefix to specify the level of the annotation. By
    default, the image manifest is annotated. The following example adds the
    `foo=bar` annotation the image index instead of the manifests:

    ```console
    $ docker buildx build -t TAG --annotation "index:foo=bar" --push .
    ```

    You can specify multiple types, separated by a comma (,) to add the annotation
    to multiple image components. The following example adds the `foo=bar`
    annotation to image index, descriptors, manifests:

    ```console
    $ docker buildx build -t TAG --annotation "index,manifest,manifest-descriptor:foo=bar" --push .
    ```

    You can also specify a platform qualifier in square brackets (`[os/arch]`) in
    the type prefix, to apply the annotation to a subset of manifests with the
    matching platform. The following example adds the `foo=bar` annotation only to
    the manifest with the `linux/amd64` platform:

    ```console
    $ docker buildx build -t TAG --annotation "manifest[linux/amd64]:foo=bar" --push .
    ```

    Wildcards are not supported in the platform qualifier; you can't specify a type
    prefix like `manifest[linux/*]` to add annotations only to manifests which has
    `linux` as the OS platform.

    For more information about annotations, see
    [Annotations](/build/building/annotations/).

    ### Create attestations (--attest) {#attest}

    ```text
    --attest=type=sbom,...
    --attest=type=provenance,...
    ```

    Create [image attestations](/build/attestations/).
    BuildKit currently supports:

    - `sbom` - Software Bill of Materials.

      Use `--attest=type=sbom` to generate an SBOM for an image at build-time.
      Alternatively, you can use the [`--sbom` shorthand](#sbom).

      For more information, see [here](/build/attestations/sbom/).

    - `provenance` - SLSA Provenance

      Use `--attest=type=provenance` to generate provenance for an image at
      build-time. Alternatively, you can use the [`--provenance` shorthand](#provenance).

      By default, a minimal provenance attestation will be created for the build
      result, which will only be attached for images pushed to registries.

      For more information, see [here](/build/attestations/slsa-provenance/).

    ### Allow extra privileged entitlement (--allow) {#allow}

    ```text
    --allow=ENTITLEMENT
    ```

    Allow extra privileged entitlement. List of entitlements:

    - `network.host` - Allows executions with host networking.
    - `security.insecure` - Allows executions without sandbox. See
      [related Dockerfile extensions](/engine/reference/builder/#run---securitysandbox).

    For entitlements to be enabled, the `buildkitd` daemon also needs to allow them
    with `--allow-insecure-entitlement` (see [`create --buildkitd-flags`](buildx_create.md#buildkitd-flags)).

    ```console
    $ docker buildx create --use --name insecure-builder --buildkitd-flags '--allow-insecure-entitlement security.insecure'
    $ docker buildx build --allow security.insecure .
    ```

    ### Set build-time variables (--build-arg) {#build-arg}

    Same as [`docker build` command](/engine/reference/commandline/image_build/#build-arg).

    There are also useful built-in build arguments, such as:

    * `BUILDKIT_CONTEXT_KEEP_GIT_DIR=<bool>`: trigger git context to keep the `.git` directory
    * `BUILDKIT_INLINE_CACHE=<bool>`: inline cache metadata to image config or not
    * `BUILDKIT_MULTI_PLATFORM=<bool>`: opt into deterministic output regardless of multi-platform output or not

    ```console
    $ docker buildx build --build-arg BUILDKIT_MULTI_PLATFORM=1 .
    ```

    Learn more about the built-in build arguments in the [Dockerfile reference docs](/engine/reference/builder/#buildkit-built-in-build-args).

    ### Additional build contexts (--build-context) {#build-context}

    ```text
    --build-context=name=VALUE
    ```

    Define additional build context with specified contents. In Dockerfile the context can be accessed when `FROM name` or `--from=name` is used.
    When Dockerfile defines a stage with the same name it is overwritten.

    The value can be a local source directory, [local OCI layout compliant directory](https://github.com/opencontainers/image-spec/blob/main/image-layout.md), container image (with docker-image:// prefix), Git or HTTP URL.

    Replace `alpine:latest` with a pinned one:

    ```console
    $ docker buildx build --build-context alpine=docker-image://alpine@sha256:0123456789 .
    ```

    Expose a secondary local source directory:

    ```console
    $ docker buildx build --build-context project=path/to/project/source .
    # docker buildx build --build-context project=https://github.com/myuser/project.git .
    ```

    ```dockerfile
    # syntax=docker/dockerfile:1
    FROM alpine
    COPY --from=project myfile /
    ```

    #### Use an OCI layout directory as build context {#source-oci-layout}

    Source an image from a local [OCI layout compliant directory](https://github.com/opencontainers/image-spec/blob/main/image-layout.md),
    either by tag, or by digest:

    ```console
    $ docker buildx build --build-context foo=oci-layout:///path/to/local/layout:<tag>
    $ docker buildx build --build-context foo=oci-layout:///path/to/local/layout@sha256:<digest>
    ```

    ```dockerfile
    # syntax=docker/dockerfile:1
    FROM alpine
    RUN apk add git
    COPY --from=foo myfile /

    FROM foo
    ```

    The OCI layout directory must be compliant with the [OCI layout specification](https://github.com/opencontainers/image-spec/blob/main/image-layout.md).
    You can reference an image in the layout using either tags, or the exact digest.

    ### Override the configured builder instance (--builder) {#builder}

    Same as [`buildx --builder`](buildx.md#builder).

    ### Use an external cache source for a build (--cache-from) {#cache-from}

    ```text
    --cache-from=[NAME|type=TYPE[,KEY=VALUE]]
    ```

    Use an external cache source for a build. Supported types are `registry`,
    `local`, `gha` and `s3`.

    - [`registry` source](https://github.com/moby/buildkit#registry-push-image-and-cache-separately)
      can import cache from a cache manifest or (special) image configuration on the
      registry.
    - [`local` source](https://github.com/moby/buildkit#local-directory-1) can
      import cache from local files previously exported with `--cache-to`.
    - [`gha` source](https://github.com/moby/buildkit#github-actions-cache-experimental)
      can import cache from a previously exported cache with `--cache-to` in your
      GitHub repository
    - [`s3` source](https://github.com/moby/buildkit#s3-cache-experimental)
      can import cache from a previously exported cache with `--cache-to` in your
      S3 bucket

    If no type is specified, `registry` exporter is used with a specified reference.

    `docker` driver currently only supports importing build cache from the registry.

    ```console
    $ docker buildx build --cache-from=user/app:cache .
    $ docker buildx build --cache-from=user/app .
    $ docker buildx build --cache-from=type=registry,ref=user/app .
    $ docker buildx build --cache-from=type=local,src=path/to/cache .
    $ docker buildx build --cache-from=type=gha .
    $ docker buildx build --cache-from=type=s3,region=eu-west-1,bucket=mybucket .
    ```

    More info about cache exporters and available attributes: https://github.com/moby/buildkit#export-cache

    ### Export build cache to an external cache destination (--cache-to) {#cache-to}

    ```text
    --cache-to=[NAME|type=TYPE[,KEY=VALUE]]
    ```

    Export build cache to an external cache destination. Supported types are
    `registry`, `local`, `inline`, `gha` and `s3`.

    - [`registry` type](https://github.com/moby/buildkit#registry-push-image-and-cache-separately) exports build cache to a cache manifest in the registry.
    - [`local` type](https://github.com/moby/buildkit#local-directory-1) exports
      cache to a local directory on the client.
    - [`inline` type](https://github.com/moby/buildkit#inline-push-image-and-cache-together)
      writes the cache metadata into the image configuration.
    - [`gha` type](https://github.com/moby/buildkit#github-actions-cache-experimental)
      exports cache through the [GitHub Actions Cache service API](https://github.com/tonistiigi/go-actions-cache/blob/master/api.md#authentication).
    - [`s3` type](https://github.com/moby/buildkit#s3-cache-experimental) exports
      cache to a S3 bucket.

    The `docker` driver only supports cache exports using the `inline` and `local`
    cache backends.

    Attribute key:

    - `mode` - Specifies how many layers are exported with the cache. `min` on only
      exports layers already in the final build stage, `max` exports layers for
      all stages. Metadata is always exported for the whole build.

    ```console
    $ docker buildx build --cache-to=user/app:cache .
    $ docker buildx build --cache-to=type=inline .
    $ docker buildx build --cache-to=type=registry,ref=user/app .
    $ docker buildx build --cache-to=type=local,dest=path/to/cache .
    $ docker buildx build --cache-to=type=gha .
    $ docker buildx build --cache-to=type=s3,region=eu-west-1,bucket=mybucket .
    ```

    More info about cache exporters and available attributes: https://github.com/moby/buildkit#export-cache

    ### Load the single-platform build result to `docker images` (--load) {#load}

    Shorthand for [`--output=type=docker`](#docker). Will automatically load the
    single-platform build result to `docker images`.

    ### Write build result metadata to the file (--metadata-file) {#metadata-file}

    To output build metadata such as the image digest, pass the `--metadata-file` flag.
    The metadata will be written as a JSON object to the specified file. The
    directory of the specified file must already exist and be writable.

    ```console
    $ docker buildx build --load --metadata-file metadata.json .
    $ cat metadata.json
    ```

    ```json
    {
      "containerimage.config.digest": "sha256:2937f66a9722f7f4a2df583de2f8cb97fc9196059a410e7f00072fc918930e66",
      "containerimage.descriptor": {
        "annotations": {
          "config.digest": "sha256:2937f66a9722f7f4a2df583de2f8cb97fc9196059a410e7f00072fc918930e66",
          "org.opencontainers.image.created": "2022-02-08T21:28:03Z"
        },
        "digest": "sha256:19ffeab6f8bc9293ac2c3fdf94ebe28396254c993aea0b5a542cfb02e0883fa3",
        "mediaType": "application/vnd.oci.image.manifest.v1+json",
        "size": 506
      },
      "containerimage.digest": "sha256:19ffeab6f8bc9293ac2c3fdf94ebe28396254c993aea0b5a542cfb02e0883fa3"
    }
    ```

    ### Ignore build cache for specific stages (--no-cache-filter) {#no-cache-filter}

    The `--no-cache-filter` lets you specify one or more stages of a multi-stage
    Dockerfile for which build cache should be ignored. To specify multiple stages,
    use a comma-separated syntax:

    ```console
    $ docker buildx build --no-cache-filter stage1,stage2,stage3 .
    ```

    For example, the following Dockerfile contains four stages:

    - `base`
    - `install`
    - `test`
    - `release`

    ```dockerfile
    # syntax=docker/dockerfile:1

    FROM oven/bun:1 as base
    WORKDIR /app

    FROM base AS install
    WORKDIR /temp/dev
    RUN --mount=type=bind,source=package.json,target=package.json \
        --mount=type=bind,source=bun.lockb,target=bun.lockb \
        bun install --frozen-lockfile

    FROM base AS test
    COPY --from=install /temp/dev/node_modules node_modules
    COPY . .
    RUN bun test

    FROM base AS release
    ENV NODE_ENV=production
    COPY --from=install /temp/dev/node_modules node_modules
    COPY . .
    ENTRYPOINT ["bun", "run", "index.js"]
    ```

    To ignore the cache for the `install` stage:

    ```console
    $ docker buildx build --no-cache-filter install .
    ```

    To ignore the cache the `install` and `release` stages:

    ```console
    $ docker buildx build --no-cache-filter install,release .
    ```

    The arguments for the `--no-cache-filter` flag must be names of stages.

    ### Set the export action for the build result (-o, --output) {#output}

    ```text
    -o, --output=[PATH,-,type=TYPE[,KEY=VALUE]
    ```

    Sets the export action for the build result. In `docker build` all builds finish
    by creating a container image and exporting it to `docker images`. `buildx` makes
    this step configurable allowing results to be exported directly to the client,
    OCI image tarballs, registry etc.

    Buildx with `docker` driver currently only supports local, tarball exporter and
    image exporter. `docker-container` driver supports all the exporters.

    If just the path is specified as a value, `buildx` will use the local exporter
    with this path as the destination. If the value is "-", `buildx` will use `tar`
    exporter and write to `stdout`.

    ```console
    $ docker buildx build -o . .
    $ docker buildx build -o outdir .
    $ docker buildx build -o - - > out.tar
    $ docker buildx build -o type=docker .
    $ docker buildx build -o type=docker,dest=- . > myimage.tar
    $ docker buildx build -t tonistiigi/foo -o type=registry
    ```

    Supported exported types are:

    #### `local`

    The `local` export type writes all result files to a directory on the client. The
    new files will be owned by the current user. On multi-platform builds, all results
    will be put in subdirectories by their platform.

    Attribute key:

    - `dest` - destination directory where files will be written

    #### `tar`

    The `tar` export type writes all result files as a single tarball on the client.
    On multi-platform builds all results will be put in subdirectories by their platform.

    Attribute key:

    - `dest` - destination path where tarball will be written. “-” writes to stdout.

    #### `oci`

    The `oci` export type writes the result image or manifest list as an [OCI image
    layout](https://github.com/opencontainers/image-spec/blob/v1.0.1/image-layout.md)
    tarball on the client.

    Attribute key:

    - `dest` - destination path where tarball will be written. “-” writes to stdout.

    #### `docker`

    The `docker` export type writes the single-platform result image as a [Docker image
    specification](https://github.com/docker/docker/blob/v20.10.2/image/spec/v1.2.md)
    tarball on the client. Tarballs created by this exporter are also OCI compatible.

    The default image store in Docker Engine doesn't support loading multi-platform
    images. You can enable the containerd image store, or push multi-platform images
    is to directly push to a registry, see [`registry`](#registry).

    Attribute keys:

    - `dest` - destination path where tarball will be written. If not specified,
      the tar will be loaded automatically to the local image store.
    - `context` - name for the Docker context where to import the result

    #### `image`

    The `image` exporter writes the build result as an image or a manifest list. When
    using `docker` driver the image will appear in `docker images`. Optionally, image
    can be automatically pushed to a registry by specifying attributes.

    Attribute keys:

    - `name` - name (references) for the new image.
    - `push` - Boolean to automatically push the image.

    #### `registry`

    The `registry` exporter is a shortcut for `type=image,push=true`.

    ### Set the target platforms for the build (--platform) {#platform}

    ```text
    --platform=value[,value]
    ```

    Set the target platform for the build. All `FROM` commands inside the Dockerfile
    without their own `--platform` flag will pull base images for this platform and
    this value will also be the platform of the resulting image.

    The default value is the platform of the BuildKit daemon where the build runs.
    The value takes the form of `os/arch` or `os/arch/variant`. For example,
    `linux/amd64` or `linux/arm/v7`. Additionally, the `--platform` flag also supports
    a special `local` value, which tells BuildKit to use the platform of the BuildKit
    client that invokes the build.

    When using `docker-container` driver with `buildx`, this flag can accept multiple
    values as an input separated by a comma. With multiple values the result will be
    built for all of the specified platforms and joined together into a single manifest
    list.

    If the `Dockerfile` needs to invoke the `RUN` command, the builder needs runtime
    support for the specified platform. In a clean setup, you can only execute `RUN`
    commands for your system architecture.
    If your kernel supports [`binfmt_misc`](https://en.wikipedia.org/wiki/Binfmt_misc)
    launchers for secondary architectures, buildx will pick them up automatically.
    Docker desktop releases come with `binfmt_misc` automatically configured for `arm64`
    and `arm` architectures. You can see what runtime platforms your current builder
    instance supports by running `docker buildx inspect --bootstrap`.

    Inside a `Dockerfile`, you can access the current platform value through
    `TARGETPLATFORM` build argument. Refer to the [`docker build`
    documentation](/engine/reference/builder/#automatic-platform-args-in-the-global-scope)
    for the full description of automatic platform argument variants .

    You can find the formatting definition for the platform specifier in the
    [containerd source code](https://github.com/containerd/containerd/blob/v1.4.3/platforms/platforms.go#L63).

    ```console
    $ docker buildx build --platform=linux/arm64 .
    $ docker buildx build --platform=linux/amd64,linux/arm64,linux/arm/v7 .
    $ docker buildx build --platform=darwin .
    ```

    ### Set type of progress output (--progress) {#progress}

    ```text
    --progress=VALUE
    ```

    Set type of progress output (`auto`, `plain`, `tty`). Use plain to show container
    output (default "auto").

    > **Note**
    >
    > You can also use the `BUILDKIT_PROGRESS` environment variable to set its value.

    The following example uses `plain` output during the build:

    ```console
    $ docker buildx build --load --progress=plain .

    #1 [internal] load build definition from Dockerfile
    #1 transferring dockerfile: 227B 0.0s done
    #1 DONE 0.1s

    #2 [internal] load .dockerignore
    #2 transferring context: 129B 0.0s done
    #2 DONE 0.0s
    ...
    ```

    > **Note**
    >
    > Check also our [Color output controls guide](https://github.com/docker/buildx/blob/master/docs/guides/color-output.md)
    > for modifying the colors that are used to output information to the terminal.

    ### Create provenance attestations (--provenance) {#provenance}

    Shorthand for [`--attest=type=provenance`](#attest), used to configure
    provenance attestations for the build result. For example,
    `--provenance=mode=max` can be used as an abbreviation for
    `--attest=type=provenance,mode=max`.

    Additionally, `--provenance` can be used with Boolean values to enable or disable
    provenance attestations. For example, `--provenance=false` disables all provenance attestations,
    while `--provenance=true` enables all provenance attestations.

    By default, a minimal provenance attestation will be created for the build
    result. Note that the default image store in Docker Engine doesn't support
    attestations. Provenance attestations only persist for images pushed directly
    to a registry if you use the default image store. Alternatively, you can switch
    to using the containerd image store.

    For more information about provenance attestations, see
    [here](/build/attestations/slsa-provenance/).

    ### Push the build result to a registry (--push) {#push}

    Shorthand for [`--output=type=registry`](#registry). Will automatically push the
    build result to registry.

    ### Create SBOM attestations (--sbom) {#sbom}

    Shorthand for [`--attest=type=sbom`](#attest), used to configure SBOM
    attestations for the build result. For example,
    `--sbom=generator=<user>/<generator-image>` can be used as an abbreviation for
    `--attest=type=sbom,generator=<user>/<generator-image>`.

    Additionally, `--sbom` can be used with Boolean values to enable or disable
    SBOM attestations. For example, `--sbom=false` disables all SBOM attestations.

    Note that the default image store in Docker Engine doesn't support
    attestations. Provenance attestations only persist for images pushed directly
    to a registry if you use the default image store. Alternatively, you can switch
    to using the containerd image store.

    For more information, see [here](/build/attestations/sbom/).

    ### Secret to expose to the build (--secret) {#secret}

    ```text
    --secret=[type=TYPE[,KEY=VALUE]
    ```

    Exposes secret to the build. The secret can be used by the build using
    [`RUN --mount=type=secret` mount](/engine/reference/builder/#run---mounttypesecret).

    If `type` is unset it will be detected. Supported types are:

    #### `file`

    Attribute keys:

    - `id` - ID of the secret. Defaults to base name of the `src` path.
    - `src`, `source` - Secret filename. `id` used if unset.

    ```dockerfile
    # syntax=docker/dockerfile:1
    FROM python:3
    RUN pip install awscli
    RUN --mount=type=secret,id=aws,target=/root/.aws/credentials \
      aws s3 cp s3://... ...
    ```

    ```console
    $ docker buildx build --secret id=aws,src=$HOME/.aws/credentials .
    ```

    #### `env`

    Attribute keys:

    - `id` - ID of the secret. Defaults to `env` name.
    - `env` - Secret environment variable. `id` used if unset, otherwise will look for `src`, `source` if `id` unset.

    ```dockerfile
    # syntax=docker/dockerfile:1
    FROM node:alpine
    RUN --mount=type=bind,target=. \
      --mount=type=secret,id=SECRET_TOKEN \
      SECRET_TOKEN=$(cat /run/secrets/SECRET_TOKEN) yarn run test
    ```

    ```console
    $ SECRET_TOKEN=token docker buildx build --secret id=SECRET_TOKEN .
    ```

    ### Size of /dev/shm (--shm-size) {#shm-size}

    The format is `<number><unit>`. `number` must be greater than `0`. Unit is
    optional and can be `b` (bytes), `k` (kilobytes), `m` (megabytes), or `g`
    (gigabytes). If you omit the unit, the system uses bytes.

    ### SSH agent socket or keys to expose to the build (--ssh) {#ssh}

    ```text
    --ssh=default|<id>[=<socket>|<key>[,<key>]]
    ```

    This can be useful when some commands in your Dockerfile need specific SSH
    authentication (e.g., cloning a private repository).

    `--ssh` exposes SSH agent socket or keys to the build and can be used with the
    [`RUN --mount=type=ssh` mount](/engine/reference/builder/#run---mounttypessh).

    Example to access Gitlab using an SSH agent socket:

    ```dockerfile
    # syntax=docker/dockerfile:1
    FROM alpine
    RUN apk add --no-cache openssh-client
    RUN mkdir -p -m 0700 ~/.ssh && ssh-keyscan gitlab.com >> ~/.ssh/known_hosts
    RUN --mount=type=ssh ssh -q -T git@gitlab.com 2>&1 | tee /hello
    # "Welcome to GitLab, @GITLAB_USERNAME_ASSOCIATED_WITH_SSHKEY" should be printed here
    # with the type of build progress is defined as `plain`.
    ```

    ```console
    $ eval $(ssh-agent)
    $ ssh-add ~/.ssh/id_rsa
    (Input your passphrase here)
    $ docker buildx build --ssh default=$SSH_AUTH_SOCK .
    ```

    ### Set ulimits (--ulimit) {#ulimit}

    `--ulimit` is specified with a soft and hard limit as such:
    `<type>=<soft limit>[:<hard limit>]`, for example:

    ```console
    $ docker buildx build --ulimit nofile=1024:1024 .
    ```

    > **Note**
    >
    > If you don't provide a `hard limit`, the `soft limit` is used
    > for both values. If no `ulimits` are set, they're inherited from
    > the default `ulimits` set on the daemon.
deprecated: false
hidden: false
experimental: false
experimentalcli: false
kubernetes: false
swarm: false