Insufficient mock data in the staging environment? Like no BYOIP prefixes at all? Since even one prefix should have shown that it would be deleted by that subtask...

From all the recent outages, it sounds like Cloudflare is barely tested at all. Maybe they have lots of unit tests etc, but they do not seem to test their whole system... I get that their whole setup is vast, but even testing that subtask manually would have surfaced the bug

Testing the "whole system" for a mature enterprise product is quite difficult. The combinatorial explosion of account configurations and feature usage becomes intractable on two levels: engineers can't anticipate every scenario they need their tests to cover (because the product is too big understand the whole of), and even if comprehensive testing was possible - it would be impractical on some combination of time, flakiness, and cost.

I think Cloudflare does not sufficiently test lesser-used options. I lurk in the R2 Discord and a lot of users seem to have problems with custom domains.

It was also merged 15 days prior to production release...however, you're spot on with the empty test. That's a basic scenario that if it returned all...is like oh no.

Just crazy. Why does a staging environment matter? They should be running some integration tests against eg an in memory database for these kinds of tasks surely?

my guess is the company is rotting from the inside and drowning in tech debt