Angband is versioned x.y.z.
- A release that changes X carries major changes with far-reaching implications
- A release that changes Y carries gameplay changes of a less paradigm-shattering kind
- A release that changes Z may have small gameplay changes and bugfixes.
Savefile compatibility will be ensured across X.Y.*, X.* releases would be able to import Y-1 releases, and X releases make no guarantees.
There will be no 'stable' and 'unstable' releases, but we will keep Git HEAD playable as much as possible, with nightlies for people who want to be on the bleeding edge.