Architectures¶

snapcraft.yaml¶

The architectures how-to guide provides examples of how to use the platforms and architectures key.

core24¶

snapcraft.yaml¶

platforms:
    <platform 1>:
        build-on: [<arch 1>, <arch 2>]
        build-for: [<arch 1>]
    <platform 2>:
        build-on: [<arch 3>]
        build-for: [<arch 4>]
    ...

platform¶

The platform name describes a build-on/build-for pairing. If the platform name is a valid debian architecture, then build-on and build-for can be omitted (see below for details).

For a list of supported architectures, see Supported CPU architectures.

The recommended platform name is the build-for arch.

build-on¶

The build-on field is an optional list of architectures where the snap can be built. It can contain multiple architectures.

If the platform name is a valid architecture and build-for is not defined, then build-on can be omitted. build-on will assume the platform name.

build-for¶

The build-for field is an optional single-element list containing the architecture where the snap should run.

If the platform name is a valid architecture, then build-for will assume the platform name.

build-for: [all] is a special key to denote an architecture-independent snap. If the all key is used, no other build-on/build-for pairs can be defined. See this page to learn how to use the all key.

all cannot be used for build-on.

core22¶

The root key architectures defines a list of build-on->build-for pairs with the following syntax:

snapcraft.yaml¶

architectures:
  - build-on: [<arch 1>, <arch 2>]
    build-for: [<arch 1>]
  - build-on: [<arch 3>]
    build-for: [<arch 4>]

For a list of supported architectures, see Supported CPU architectures.

Data types¶

If the value is a single item, it can be written as a single element list or a scalar. For example:

snapcraft.yaml¶

architectures:
  - build-on: amd64
    build-for: arm64

is equivalent to:

snapcraft.yaml¶

architectures:
  - build-on: [amd64]
    build-for: [arm64]

Note

Using a list is the recommended syntax. Scalars are not recommended.

`build-on`¶

The build-on field is required and can contain multiple architectures.

`build-for`¶

The build-for field is optional and should be a single element list. If it is not defined, the build-for will be set the build-on for each build in the build plan.

all cannot be used for build-on.

The same architecture cannot be defined in multiple build-for entries.

core20¶

The above syntax and rules for core22 apply for core20 except that run-on is used in place of build-for. Additionally, core20 supports multiple architectures in the run-on field, which will create multi-architecture snaps.

Shorthand format¶

Legacy behavior

Shorthand architectures are resolved differently depending on the snap’s base. In core20 snaps, declaring multiple shorthand architectures yields a single multi-architecture artifact.

As an alternative to the explicit format described above, core20 snaps support a shorthand format can be used for simple multi-architecture build-on definitions.

snapcraft.yaml¶

architectures: [amd64, arm64]

is equivalent to:

snapcraft.yaml¶

architectures:
  - build-on: [amd64, arm64]

The explicit and shorthand format cannot be mixed.

Project variables¶

core24¶

Project variable	Description
`CRAFT_ARCH_BUILD_FOR`	The architecture of the platform the snap is built for.
`CRAFT_ARCH_BUILD_ON`	The architecture of the platform the snap is built on.
`CRAFT_ARCH_TRIPLET_BUILD_FOR`	The architecture triplet of the platform the snap is built for.
`CRAFT_ARCH_TRIPLET_BUILD_ON`	The architecture triplet of the platform the snap is built on.

core22¶

Project variable	Description
`CRAFT_ARCH_BUILD_FOR`	The architecture of the platform the snap is built for.
`CRAFT_ARCH_BUILD_ON`	The architecture of the platform the snap is built on.
`CRAFT_ARCH_TRIPLET_BUILD_FOR`	The architecture triplet of the platform the snap is built for.
`CRAFT_ARCH_TRIPLET_BUILD_ON`	The architecture triplet of the platform the snap is built on.
`CRAFT_ARCH_TRIPLET`	deprecated: use `CRAFT_ARCH_TRIPLET_BUILD_FOR` instead
`CRAFT_TARGET_ARCH`	deprecated: use `CRAFT_ARCH_BUILD_FOR` instead

core20¶

core20 snaps use the terminology run-on in the architectures field in the project file. The project variables and documentation use the preferred term build-for.

Project variable	Description
`SNAPCRAFT_ARCH_BUILD_FOR`	The architecture of the platform the snap is built for.
`SNAPCRAFT_ARCH_BUILD_ON`	The architecture of the platform the snap is built on.
`SNAPCRAFT_ARCH_TRIPLET_BUILD_FOR`	The architecture triplet of the platform the snap is built for.
`SNAPCRAFT_ARCH_TRIPLET_BUILD_ON`	The architecture triplet of the platform the snap is built on.
`SNAPCRAFT_ARCH_TRIPLET`	The architecture triplet specified by `--target-arch`. If a target arch is not provided, then the architecture of the build-on platform is used.
`SNAPCRAFT_TARGET_ARCH`	The architecture specified by `--target-arch`. If a target arch is not provided, then the architecture of the build-on platform is used.

SNAPCRAFT_ARCH_BUILD_FOR and SNAPCRAFT_ARCH_TRIPLET_BUILD_FOR are not available in any of the following scenarios:

when the build-for architecture is not in the list of supported architectures
when building a multi-architecture snap

Supported CPU architectures¶

core22 and higher¶

Local builds¶

Snapcraft supports building for these architectures locally:

amd64
arm64
armhf
ppc64el
riscv64
s390x

Launchpad builds¶

Launchpad supports remote building for these architectures:

amd64
arm64
armhf
ppc64el
riscv64
s390x

core20¶

Local builds¶

Snapcraft supports building for these architectures locally:

amd64
arm64
armhf
i386
powerpc
ppc64el
riscv64
s390x

Launchpad builds¶

Launchpad supports remote building for these architectures:

amd64
arm64
armhf
i386
ppc64el
riscv64
s390x

Environment variables and command line arguments¶

core22¶

The command line argument --build-for=<arch> or environment variable SNAPCRAFT_BUILD_FOR=<arch> is used to build a single snap package for an architecture. It selects a single build-on->build-for pair from the build plan. It does not allow building a snap not defined by the build plan.

The command line argument takes priority over the environment variable.

See Build plans for more information on how build plans are created.

core20¶

--target-arch=<arch> is used for cross-compiling in core20. It adds repositories for the target arch, which are used for stage-packages. The target arch does not need to be listed in the architectures key.

The --target-arch argument can only be used in destructive mode and with --enable-experimental-target-arch or the environment variable SNAPCRAFT_ENABLE_EXPERIMENTAL_TARGET_ARCH.

The full usage is snapcraft --destructive-mode --enable-experimental-target-arch --target-arch=<arch>.