Updated a pet project of mine and got a minor break:
var pixels = new uint[renderers.width * renderers.height];
var pixels2 = MemoryMarshal.Cast<uint, ulong>(pixels);
pixels2[idx] = ...
Spans is such a fundamental tool for low level programming. It is really unfortunate they were added relatively late to the language. Now every new version includes a slew of improvements related to them but they will never be as good as if they were there from the start or at least as early as generics were.