validation-sets

A validation set is an assertion that lists specific snaps that are either required to be installed together or are permitted to be installed together on a device or system.

They can be created using the snapcraft command, and monitored with the snap command. See How to manage validation sets for further details.

For devices running Ubuntu Core, they can be declared as part of the model definition. For Landscape-managed devices, see How to manage snaps in Landscape with validation sets after a validation set has been created.

Why use a validation set

A validation set can help a group of interdependent snaps maintain their testing and certification integrity, as well as help orchestrate their updates. But they can equally be used to simplify dependency deployment and to help manage devices.

In particular, if the model assertion for a device includes optional snaps, a validation set can be used to ensure specific collections of snaps are installed together on derivatives of the same devices.