What I heard Eelco say in a recent conference is that 'nix build' will work with 'old flakes' but as soon as you do a 'nix flake update ' you might have to ada

What I heard Eelco say in a recent conference is that 'nix build' will work with 'old flakes' but as soon as you do a 'nix flake update ' you might have to adapt your flake to the new conventions.