Use GitHub from your Mac

Three ways to clone and push: a key on the Mac, agent forwarding, or the GitHub CLI.

Option 1: a key that lives on the Mac (best for CI)

On your RunMac, over SSH:

ssh-keygen -t ed25519 -C "runmac"
cat ~/.ssh/id_ed25519.pub

Copy the line it prints. In GitHub, go to your profile picture → Settings → SSH and GPG keys → New SSH key, paste it and save. For a CI runner that only needs one repository, add it as a deploy key in that repository’s settings instead. Then test:

ssh -T git@github.com

GitHub answers “Hi USERNAME! You’ve successfully authenticated, but GitHub does not provide shell access.”

Option 2: forward the key from your own computer

Your key never leaves your computer. Add ForwardAgent yes to the RunMac entry in your computer’s ~/.ssh/config (see the SSH shortcut):

Host runmac
  HostName k7p2x9.runmac.dev
  Port 2201
  User dev
  ForwardAgent yes

Make sure your key is loaded (ssh-add -L), connect with ssh runmac, and ssh -T git@github.com on the Mac answers as you. Only turn this on for hosts you trust, never for Host *. Use SSH URLs (git@github.com:…), not HTTPS.

Option 3: the GitHub CLI

brew install gh
gh auth login

Follow the prompts; it can sign in through a one-time code you enter at github.com on your own computer.