λ sh <(curl https://nixos.org/nix/install) --daemon
λ source /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh
λ nix-build https://github.com/hercules-ci/nix-darwin/archive/hercules-ci-agent.tar.gz -A installer
λ ./result/bin/darwin-installer
~/.nixpkgs/darwin-configuration.nix
services.nix-daemon.enable = true;
services.hercules-ci-agent.enable = true;
λ source /etc/static/bashrc
λ sudo chown -R hercules-ci-agent:hercules-ci-agent /var/lib/hercules-ci-agent/
λ sudo install \
-o hercules-ci-agent \
-m 0600 \
cluster-join-token.key \
/var/lib/hercules-ci-agent/secrets/cluster-join-token.key
λ rm cluster-join-token.key