Fossil not only implies a self-hosted solution, just as Gitlab does, but it also implies switching to a largely unknown tool.
If we are happy with a self-hosted solution, I'll state that the thought of offering hosting (and paying for hosting) GNUstep's infrastructure occurred to me -- however it implies taking over sysadmin responsibilities, including responsibility for users' credentials. Less responsibility for third-party data = "" ivucica.
And I'm also not sure we want to self host. Delegating sysadmin responsibilities is a good thing. But if we do want to run our own infrastructure, I'm happy to offer to set up a nice environment for the contributors (and document what was done along the way). This would be built around Samba4-based authentication database, which conveniently means the possibility of using the same credentials in any tool that can authenticate against LDAP, or even authenticate using Kerberos.
(And if FSF or some other kind and trusted party has spare hardware capacity, that's even better.)