I have written a patch for that some time ago, that oas never merged. See https://issues.guix.gnu.org/39530 :)

Let's see if I can make progress on this!

Le 24 novembre 2020 12:01:41 GMT-05:00, Abraham Jose <abraham.juegos1237@gmail.com> a écrit :
>For people like me with an inestable internet having to download big
>packages is a pain because as soon as the package download is cancelled
>due
>to networking issues you have to start all over again. Having a
>rsync-like
>way of cancelling/stop a download and continue it later could improve
>the
>QOL of many users.