I've been dabbling with the newer Cap'n Web, whose nicely descriptive README's first line says:

> Cap'n Web is a spiritual sibling to Cap'n Proto (and is created by the same author), but designed to play nice in the web stack.

It's just JSON, which has up and down sides. But things like promise pipelining are such a huge upside versus everything else: you can refer to results (and maybe send them around?) and kick off new work based on those results, before you even get the result back.

This is far far far superior to everything else, totally different ball-game.

I've been a little rebuffed by wasm when I try, keep getting too close to some gravitational event horizon & get sucked in & give up, but for more data-throughput oriented systems, I'm still hoping wrpc ends up being a fantastic pick. https://github.com/bytecodealliance/wrpc . Also Apache Arrow Flight, which I know less about, has mad traction in serious data-throughput systems, which being adjacent to amazingly popular Apache Arrow makes sense. https://arrow.apache.org/docs/format/Flight.html