Snapcraft 9.1 release notes¶

08 September 2026

Learn about the new features, changes, and fixes introduced in Snapcraft 9.1.

Requirements and compatibility¶

See System requirements for information on the minimum hardware and installed software.

What’s new¶

Snapcraft 9.1 brings the following features, integrations, and improvements.

Support for Ubuntu Pro-compliant snaps¶

Snapcraft 9.1 supports packing snaps containing the extended security maintenance fixes and compliance features of Ubuntu Pro. System requirements and guidance on packing Pro-compliant snaps can be found in Pack a Pro-compliant snap.

Kernel and initrd plugins¶

The Kernel plugin has been reworked and is no longer experimental.

A companion Initrd plugin has also been added for building the initial ramdisk used by a kernel snap.

Experimental ROS 2 Lyrical extension¶

The experimental ros2-lyrical extension has been added for core26 snaps, joining the existing ros2-humble and ros2-jazzy extensions for core22 and core24, respectively.

Experimental .NET 11 extension¶

The experimental dotnet11 extension has been added for apps targeting .NET 11.

Support for armv8l¶

64-bit ARM systems can now natively build ARMHF snaps by setting the environment variable CRAFT_BUILD_ON=armhf. Snapcraft recognizes the armv8l machine type, reported by these systems when running a 32-bit userspace, and maps it to ARMHF.

Minor features¶

Snapcraft 9.1 brings the following minor changes.

Conditional repacking¶

To speed up redundant snapcraft pack commands, Snapcraft now only repacks snaps if the source changed or the snap’s metadata need to be updated. This is useful when iterating with snapcraft test, as unchanged snaps aren’t rebuilt between test runs.

Per-component compression¶

Components can now set their own compression in the project file, overriding the compression algorithm used for the snap itself. This is useful when a component’s payload is already heavily compressed, such as a large language model’s weights. Compressing it again with the snap’s default algorithm increases decompression time at runtime without meaningfully reducing its size.

Agents file¶

An AGENTS.md file has been added to the root of the repository, describing the codebase and practices for developers using AI coding agents to assist with their contributions to Snapcraft.

Backwards-incompatible changes¶

The following changes are incompatible with previous versions of Snapcraft.

Removed Matter SDK plugin¶

The experimental Matter SDK plugin has been removed. It was originally added to simplify building the Matter SDK, which required patches to the upstream source code. Those patches have since been merged into the Matter project, so the plugin is no longer needed. If your snap used the Matter SDK plugin, follow Matter’s compilation guide as done in the Chip Tool snap.

Feature deprecations¶

The following features are deprecated in Snapcraft 9.1:

`ua-services` key for core24 and higher¶

The ua-services key was unused for core24 and higher snaps. It’s now been deprecated in favor of the new --pro=<services> command-line option described in Pack a Pro-compliant snap.

Non-SPDX compliant licenses¶

Setting the license key to a value that isn’t a valid SPDX license expression is now deprecated. Non-SPDX values are still accepted, but won’t be allowed in future bases.

Fixed bugs and issues¶

The following issues have been resolved in Snapcraft 9.1.

Snapcraft 9.1.0¶

craft-application#1073 --debug wouldn’t enter a debug shell for failures after the prime step, such as a failure to run snap pack.
craft-archives#229 When retrieving the signing key for a package repository, GPG wouldn’t use the system’s proxy.
craft-cli#449 Deprecated commands appeared in the See also section of command help text.
craft-parts#1396 Certain network errors while downloading file sources produced a raw traceback instead of a clear error message.
craft-parts#1562 The organize key allowed organizing files from outside the install directory.
snapcraft#6327 Desktop extensions incorrectly set LD_LIBRARY_PATH, preventing Snapcraft from setting its own default value and breaking library loading.
snapcraft#6399 GPU and desktop extensions tried to write to /snap/command-chain/ at build time.

Contributors¶

We would like to express a big thank you to all the people who contributed to this release.

@asanvaq, @bepri, @canon-cat, @cmatsuoka, @dilyn-corner, @EdmilsonRodrigues, @elijahgreenstein, @florcabral, @gcomneno, @giusebar, @imatrisciano, @jahn-junior, @kubiko, @lengau, @mateusrodrigues, @medubelko, @MirkoFerrati, @Mohit-Chachada, @mr-cal, @PraaneshSelvaraj, @shaloo, @smethnani, @soumyaDghosh, @steinbro, @Tejas-Raj01, @tigarmo, @upils, and @zhijie-yang