Geoff Cant Whitelabel Erlang covers the trials, tribulations and technologies used in building a whitelabel ejabberd hosting service. The talk explains the rationale behind the choices of web server, templating system, email module, page optimizers and other web framework components. The talk also covers the documented and undocumented DNS query and caching modules in OTP and introduces 'dns' - a convenient new API for using them. Finally, the talk describes some tips and tricks useful for whitelabel hosting solutions that require customer DNS updates.