I'm moving to nix. I use a combination of macports and brew, and brew's current behavior is unusable for me, so it's going to be relegated to "use brew for package X until I find an alternate solution for package X".

I don't want to have to keep updating brew just to keep from having to wait ever-increasing amounts of time when I want to install a new package or upgrade a specific one. I never have these issues with macports, and won't have them with nix.