Re: Best-practice to "develop" a system-config / service?

[Hartmut Goebel <h.goebel@crazy-compilers.com>]

Am 11.11.2017 um 12:31 schrieb Ludovic Courtès:
> I think all you want, to test your KDE service, is to:
>
>   1. Write an OS config that uses the service.
>
>   2. Run “./pre-inst-env guix system vm that-config.scm”, run the VM,
>      and check if it works.
>
> That’s really all it takes to develop and test a system service.

Not in my case. Plasma heavily relies on plugins and such. I have added
about 50 package to the system configuration to make Plasma start. Now I
need [1] to iterately remove (and re-add) packages (not services!) to
learn what are actual the minimum requirements.

Creating a new VM for each iteration is *much* too time-consuming – no
matter if using "vm-image" or "vm" –, let alone since this required to
reboot the machine each time. Even if I would try to write a test-case
for this [2], each cycle would take too much time.

On a Fedora-like system I would simply 'rpm -e PACKAGENAME`.
Unfortunately guix is not able to uninstall a package it does not know
(see <https://lists.gnu.org/archive/html/guix-devel/2017-11/msg00160.html>).

[1] It "need" since I want to deliver a high-qualify service definition.
Otherwise I could live with these 50 packages.
[2] Which is hard, since I would need to figure out how to test "the
Plasma beast is running".

> You seemed to be willing to start a GuixSD VM that does *not* use the
> service you want to test, 

Nope. I want to start a GuixSD VM that *does* use the service, but I
need to remove and add *package* in the machine.

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
| www.crazy-compilers.com | compilers which you thought are impossible |