At least until there's actual support from NixOS for the new M1 chip...
The Ethereum dapptools suite relies on the NixOS package management system. Installation was pretty simple in previous architectures, but if you find yourself with a new Mac with the M1 chip, there is an extra step.
NixOS is the prerequisite, so you need to install that first. Using a terminal, do
# You must be a sudoer
curl -L https://nixos.org/nix/install | sh
# Run this or login again to use Nix
. "$HOME/.nix-profile/etc/profile.d/nix.sh"
Now, before trying to install dapptools, you need to edit /etc/nix/nix.conf and add the following line, if it doesn't exist:
system = x86_64-darwin
This tells NixOS to use the old Intel architecture (via Rosetta) for its packages.
Note you will need to edit /etc/nix/nix.conf via sudo.
After you've done this, you should be good to go to install dapptools:
curl https://dapp.tools/install | sh