When we remove the prerequisite of the invite code, there's a risk we might get spammed with new accounts or have a large amount of signups, that our service cannot yet handle. We need to prepare for these. Note: This concerns account creation, not Wikibase creation, there already exists a limit of 6 for that. Current sign up rate is max. 4ish new Wikibases created per week. No metrics on accounts.
Based on the outcome of https://phabricator.wikimedia.org/T335960, we want to introduce alerting on our sign up rate, so that we know when we might run into a potential issue and act.
AC:
- We have metrics in place that allow us handling alerts as described in https://phabricator.wikimedia.org/T335960 (needs timeframe and amount)