Currently when a user deletes themselves in MusicBrainz, their username and email gets updated and propagated to Discourse. However, it doesn't fully delete the account on Discourse, so we can increase the anonymisation and also unclutter the Discourse user database.

Useful Discourse API calls:

DELETE https://community.metabrainz.org/admin/users/{Discourse user id}.json

Takes boolean parameter `delete_posts` (which should be false, per IRC discussion); see API documentation for details.

GET https://community.metabrainz.org/users/by-external/{MusicBrainz account id}.json

E.g., https://community.metabrainz.org/users/by-external/229784.json - json's .user.id is the Discourse user id that can be deleted with the above call.