A nix flake is a directory containing, at least
flake.nix
flake.lock
You can create a flake, and a template, by running nix flake init in a folder.
A flake outputs expressions from its inputs
{
inputs = {
nixpkgs.url = "nixpkgs";
};
outputs = { self, nixpkgs }: {
# Define outputs here
};
}Resources and references: