If the command specified in the YAML doesn't actually exist, snapcraft provides the following non-helpful message: Command '['snap', 'pack', '--filename', 'liquidctl_test_amd64.snap', '--compression', 'xz', PosixPath('/root/prime'), PosixPath('/root/project')]' returned non-zero exit status 1. Failed to execute pack in instance. I used the following example snapcraft.yaml: name: liquidctl summary: empty description: | empty version: test base: core22 confinement: strict parts: liquidctl: plugin: python source: . stage-packages: - python3-usb apps: liquidctl: command: wrongname # Here is the line that makes it fails. plugs: - raw-usb - hardware-observe If the file could be checked, that would help to provide a helpful message for developers. snapcraft --version snapcraft 8.0.1