There was one place and only one place where we violated that, and it was in code I worked on. It was a low level module used everywhere else for bootstrapping, and so we collectively decided to do something sneaky in order to avoid making the entire code base async.

And while I find that most of the time people can handle making one special case for a rule, it was a complicated system and even “we” screwed it up occasionally for a good long while.

The problem was we needed to make a consul call at startup and the library didn’t have a synchronous way to make that call. So all bootstrapping code had to call a function and await it, before loading other things that used that module. At the end we had about a dozen entry points (services, dev and diagnostic tools). And I always got blamed because nobody seemed to remember we decided this together.

I hate singletons. And I ended up with one of only two in the whole project, and that hatred still wasn’t enough to prevent hitting the classical problems with singletons.