[zzo38computer]

> I’m wondering if the design space for new protocols should really be constrained to layers on top of HTTP

It shouldn't. For some cases it helps, but other times it doesn't. Sometimes it helps but there would be better ways to do it, making it on a simpler protocol or making an entirely new protocol (which might or might not use TCP; sometimes it is better to use TCP and sometimes not) depending on the specific case.

> Stuff like file sharing or groupware, mail, calendars, and so on—these things could be a lot more efficient and don’t really need the overhead of JSON as the message interchange format, IMHO

I dislike JSON. I think it has many problems, and that DER is a better format.

(There are also the "small web" protocols such as Gemini and Scorpion and Spartan and Titan, which avoids some of the complexity of HTTP; I had considered using DER-over-Scorpion rather than JSON-over-HTTP. It is also possible to use SSH, although SSH does not have virtual hosting.)

[afiori]

Is der the same as ASN.1?

[zzo38computer]

DER is one of the formats of ASN.1 (in my opinion it is the only good one).