unable to create new user on staging

[tansaku]

tried with and without resume:

[tansaku]

nothing helpful in the logs:

dokku> logs metplus-pets-staging
2018-12-21T13:03:07.439203059Z app[web.1]: [15] Puma starting in cluster mode...
2018-12-21T13:03:07.439257361Z app[web.1]: [15] * Version 3.12.0 (ruby 2.3.3-p222), codename: Llamas in Pajamas
2018-12-21T13:03:07.439266661Z app[web.1]: [15] * Min threads: 5, max threads: 5
2018-12-21T13:03:07.439270361Z app[web.1]: [15] * Environment: production
2018-12-21T13:03:07.439273861Z app[web.1]: [15] * Process workers: 2
2018-12-21T13:03:07.439277161Z app[web.1]: [15] * Preloading application
2018-12-21T13:03:13.651215670Z app[web.1]: [15] * Listening on tcp://0.0.0.0:5000
2018-12-21T13:03:13.651276173Z app[web.1]: [15] Use Ctrl-C to stop
2018-12-21T13:03:13.657989008Z app[web.1]: [15] - Worker 0 (pid: 212) booted, phase: 0
2018-12-21T13:03:13.658001809Z app[web.1]: [15] - Worker 1 (pid: 216) booted, phase: 0

[tansaku]

however did get an airbrake error on this:

[tansaku]

makes it look like the absence of the mailgun env/config vars is probably part of this. Ideally staging would have a mail setup so that any email was diverted to a small number of admin users ...