On Thu, 12 Sep 2019 19:03:02 +0200
Michał Górny <mgorny@gentoo.org> wrote:

> ebuild spire-0.8.1.ebuild fetch
> tar -xf ${DISTDIR}/spire-0.8.1.tar.gz
> cd spire-0.8.1/
> go mod vendor
> cd ../
> tar -cf spire-0.8.1-vendor.tar spire-0.8.1/vendor
> 
> Now you don't need special src_prepare() to unpack it.

Of course, that means if spire-0.8.1 and spire-0.8.2 use identical
vendor dirs, you can no longer trivially bump the version on the dist
without a manual re-tar.