> What does it even mean "a non-free service"?
A canonical definition may be difficult, but I think that we can agree
that at least, all the services for which their "core" software (core in
the sense of the service that they provide, different than other similar
services) is non-free, can be called "non-free services".
Interested people can have a look at
for some ideas about free/nonfree services.
About storm.debian.net, I can give some details since I am one of the
Service description: https://wiki.debian.org/
The software (sandstorm, Apache2 licensed, details in sandstorm.io) is
run in a machine by a Debian Developer, and kindly offered to the whole
Debian community, for any contributor that wants to use it.
Being myself user and admin, I can create and manage user accounts, send
invitations for people to join, explain how it works and assist in
questions/issues, etc. Ping me by mail off list or in #debian-outreach
if you need anything.
Does it work well? I would say yes! I see it used every day by several
different persons. I use it myself too!. I recall storm.debian.net being
used in the past for at least one GSoC project in Debian (the mentor
asked for an account for the student). Of course you can also find
Don't like the colors! Allows to sign in using GitHub/Google accounts!).
In summary, I would leave the decision about which tools to use to the
particular mentor+applicant pair. If anybody decides to try/use storm,
ping me for anything, I'm happy to help.