[bug#50054] [PATCH] gnu: Add bgfx

[Andy Tai]

> First things first, this still does a build of everything at once
> rather than one package per repo.  Have you looked into the one package
> per repo thing and decided that it's not possible or do you simply
> continue with the package as-is because it builds?
>

Hi, the author of the upstream is very opinionated; this is how how
arranges the things for this package and his documentation on how to
build mentions checking out all three repos and build them together.
I can look into his build system setup to try to build each repo
separately but that means I  need to maintain custom build inside the
package and normally I don't think distribution package maintainers
want to  go into inside the package to setup alternative build
processes separate from upstream--what goes inside the package is best
left to the author.  If you maintain essentially separate build
scripts in the original package in terms of cmake or genie, that is
outside the scope of guix and hard to maintain as you need to keep up
with new releases.

> Even if you want to do a merged build, binaries, vendored dependencies,
> etc. ought to be removed in the origins, not at build time.  I suggest
> you use a computed origin to merge the three and remove all those
> things.
>

Is there a "computed origin" example in existing package receipts in guix?