ISiteRootPlugin

I have a Mantissa application (offering) which needs to expose a SOAP
web service interface for reasons beyond my control. I've written the
web code for this, so that's not the problem, but now I need to hook it
up to the URLspace of my application, and this is where things start to
get tricky. I believe the right thing to do is to have an
ISessionlessSiteRootPlugin (the service does its own authentication)
powerup which returns my web service resource, probably implemented
using PrefixURLMixin.

It seems like the right place for this powerup to go is in my app
store... except then WebSite won't find it, so I also need to power the
site store up for IS9sSiteRootPlugin with the app store. Unfortunately,
there don't seem to be any examples of this sort of thing in any of the
public Divmod applications, barring some code in Radical that seems to
be drastically out of date, and probably wrong anyway.

So, my question is, am I on the right track here? If so, how do I go
about getting all the powering up / installation to happen correctly? If
not, what should I be trying to do here?
-- 
mithrandi, i Ainil en-Balandor, a faer Ambar

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.6 (GNU/Linux)

iEYEARECAAYFAkb9qXYACgkQpNuXDQIV94r3PgCeMKb2YII+YsCZiA3GENyJR6T2
trQAn2V4Ydsqw1d6m+wuXbL5EnBj2bYs
=xObo
-----END PGP SIGNATURE-----