[joeycodes]

Having worked on the performance bits of that code base, I always appreciated that the well-performing parts wouldn't have happened without leadership setting explicit performance goals and allocating resources to pay for monitoring and much engineering time to reach said goals.

[candiodari]

If you worked on it ... is there some doc describing the general architecture? It looks like the "frontend" is typescript + c++ and the backend is ... perhaps rust, with rust being a sort of "document server". Like: one instance of the backend code manages one savefile, for potentially many clients that then see eachother's changes.

How does webassembly <> backend communication work? I imagine it's somehow websockets. How do you proxy websocket connections to the appropriate backend? How does the C++ <> rust communication work? Protobuf perhaps?

[paulgb]

> How does webassembly <> backend communication work? I imagine it's somehow websockets. How do you proxy websocket connections to the appropriate backend?

I don't think there's much public info about this, besides what you can infer from looking at what goes over the wire (zstd-encoded binary messages). But to your question about routing wss connections to the appropriate backend, we've been working on a proxy/DNS server that does just that (by giving each backend its own ephemeral hostname). We've talked to some Figma engineers and at least on a conceptual level they do something similar (although their routing is path-based rather than DNS-based).

Our source is here if you're interested: https://github.com/drifting-in-space/spawner