Sure! So far, Odin has been awesome for doing custom allocation. Everything in the core library that allocates takes an optional allocator parameter, which means that you can use quite a few of the core libraries comfortably even in embedded contexts, and make it all sit on top of an arena in WASM's weird memoryland if you need to without an issue.

Outside of the WASM context where Odin runs into some difficult friction, systems-level work has been reasonable. I wrote a good chunk of a C/DWARF debugger in both C and Odin to compare, and Odin was by far the more pleasant language to write it in, my Odin code was much smaller because I didn't need xmacros, and I had proper namespaced enums, tagged unions, and slices, but still looked/read pretty similarly to well-written C or Go. I did have to wrap a few syscalls myself though, because the core library doesn't quite cover things like ptrace or networking yet.

I've put a fair bit of work into getting cross-platform networking into Odin's core library, hopefully we'll see it show up soon enough, and get some of those common nice-to-haves crossed off.