Great writeup and comparison. Also, serverlessq looks really interesting. I've struggled with queues quite often in the past – can't wait to give this one a try.
Author here. Haha! You are right. I admire Stripe's API and there's absolutely a lot of things in it that are my "benchmark" when it comes to good APIs. However, they return UNIX timestamps, for example, which I don't like that much (as stated in the post). They also use POST for updates, because, if I recall correctly, PUT/PATCH wasn't a thing yet when Stripe was built initially. Thanks for the comment.
Author here. I read that a couple of times already. RFC 3339 is what you should use - I should probably change that (it's what I actually meant). :) Thanks for pointing that out.
Author here. Thanks for the nice words - I appreciate it. I've read that a couple of times in the comments already. Definitely something worth considering, Stripe does this as well. Thanks for your comment.
Author here. I generally agree - IF something goes terribly wrong within the application, a 500 is definitely the way to go. The thing is - these just shouldn't happen that often. Because in that case we're having a bigger problem. :D For example I have never seen Stripe return a HTTP 500 from their API. Thing just works.