https://api.csswg.org/bikeshed/?force=1&url=https://raw.gith...
I’ve been using “libs/” for external libraries, but after reading this I’m considering “external/” for that purpose.
There is also a separate proposal from around the same time, dated one month later and very focused on C++ which I find less useful for C: “Canonical Project Structure” https://open-std.org/JTC1/SC22/WG21/docs/papers/2018/p1204r0...