There appear to be postgresql18-server, postgresql17-server, and postgresql16-server packages (and possibly others) in today’s Fedora 43. These packages are not parallel-installable. That said, having postgresql16-server available is admittedly very useful as a “compat” package in F43, since users upgrading from F42 can continue using PostgreSQL 16 without a data directory upgrade.

The Conflicts page touches on this topic:

It is acceptable to use Conflicts: in some cases involving compat packages. These are the cases where it is not feasible to patch applications to look in alternate locations for the -compat files, so the foo-devel and foo-compat-devel packages need to Conflict:. Whenever possible, this should be avoided.

However, at least postgresql17-server is not a true compat package (it's just a leaf alternative). Could we document this practice of providing “alternatives” as acceptable (with Conflicts:)?

Also, should we document somewhere the recommended way for users to switch between such package versions?