I generally have used instructions from here in the past to create repositories using repo-add which has seems to be worked fine.

https://wiki.archlinux.org/title/Pacman/Tips_and_tricks#Custom_local_repository

An example is here:

https://github.com/sutarwadi/arch-hpcstack/blob/75c1db47995d6df4748cd23081442d7cc30b8b45/update#L16

This seemed to have been enough to generate everything needed to create a signed repo.

On Sun, 1 Jan 2023, 00:09 Polarian, <polarian@polarian.dev> wrote:

Hello,

For anyone else who is on this mailing list, do you know if an Arch Wiki
page exists on this topic, if so could you link it here.

I have checked the DeveloperWiki as well and I can't see any
documentation on this, only how to build for official repository, but
not explaining the layout.

I guess the best option you got so far is to just reverse engineer the
repositories unless someone else knows the location of an ArchWiki page
covering this topic.

Good luck,
Polarian