We had covered all of these eventualities. We had an uptime badge on the repo to say whether it worked or not, and we encouraged developers to tag us on a GitHu

We had covered all of these eventualities. We had an uptime badge on the repo to say whether it worked or not, and we encouraged developers to tag us on a GitHub issue or email us directly if something seemed wrong. We were also keen to stress that this should take far less than an hour of their time. We didn't want to see dependency injection, metaprogramming, or anything overboard that showcased a developers knowledge - this is purely just to see if they can deliver code that matches a requirement in the time provided. In the case where we had downtime (once in 18 months), I just forwarded their email to HR and we spent some extra time going over code in the sit-down interview.