* The NixOS module now sets the default network name to the project name (commonly referred to as `<name>` in the option path).
If this is not desired, for instance if you need the projects to be on the same network, set `networks.default.name` in each of them.
* The NixOS module now sets the default project name. You can still set your own value with the `project.name` option.
If you did not set one, docker compose heuristically determined the name to be `store`, so you may want to set `project.name = "store"` or prepare to rename the network manually.
*`useHostStore` now uses an image derived from the `image.*` options. You may
need to enable `enableRecommendedContents` because with this change, files
like `/bin/sh` aren't added by default anymore.
* Drop obsolete NixOS 19.03, 19.09 and 20.03 from CI.
### Added
* NixOS-based containers can now run on Podman when it is configured to provide a docker socket. See the [installation docs](https://docs.hercules-ci.com/arion/#_nixos).