I've never used libp2p. When ported to zig it could possibly run on a small embedded system, say something like a ESP32? What requirements RAM/flash am I looking at, for a minimal system?
Yes, there is already a Rust version (https://github.com/libp2p/rust-libp2p) that behaves well at this level but I think we can reach a higher level of performance on this point with Zig. Also, if you look at the long term roadmap of libp2p (https://github.com/libp2p/specs/blob/master/ROADMAP.md), the mobile devices and IoT integrations for example are part of the considerations.
I would say in the coming weeks, I believe in the capacity of Zig for decentralized applications due to its intrinsic nature (simple, secure and very close to the computer), which makes me think that we could have here a viable alternative to everything that is currently done on Rust.