"random check" approach to Guix QA?

[Andy Tai <atai@atai.org>]

Hi, currently Guix QA tries to rebuild all dependent packages impacted
by a change (in majority of cases updates to a new version of a
package).  When there are a large number of dependent packages like
say 500 or 1000 or more, rebuilding all that takes a long time and
often the rebuild cannot complete, leaving the patch submission
dangling with no results.

For some things where safety is important, for example import food
safety, the regulatory authority may use random check or random
sampling as a way to check for safety, in case that there is no
resource to physically check every package.

Can the same approach be borrowed here, so when there is large number
of impacted packages from a patch, say larger than 200, Guix QA just
randomly select a subset sample out of these packages and build them,
and in case of (new) failures ask the submitter to fix the (new)
failure? And repeat this as needed.   This way patches can go thru the
QA process more quickly.