snapcraft fails if snapcraft.yaml contains apps keys with underscores: apps: pg_restore: command: pg_restore The failure message is confusing: Issues while validating snapcraft.yaml: The 'apps' property does not match the required schema: Additional properties are not allowed ('pg_basebackup', 'pg_dump', 'pg_restore', 'pg_dumpall', 'pg_isready' were unexpected) Allowing underscore here is important so my commands match the extensive documentation.