1 · curl install (recommended)
Fetches the current App ZIP, verifies its SHA-256, and installs to ~/Applications/Fathom Pro.app.
curl -fsSL https://chopstickshq.com/fathom-pro/install-fathom-pro.sh | bash
Also: https://fathompro.chopstickshq.com/install-fathom-pro.sh once DNS is set.