Ask HN: MFA for SSH. Any recommendations/experiences?

Hey HN! My employer(University) has enacted a security policy that mandates MFA on any public facing SSH servers. So far, I have found Authy(1) (whose SSH integration seems unmaintained?) and Duo (2) Any experiences or recommendations to share? (1) - https://github.com/authy/authy-ssh (2) - https://duo.com/pricing/duo-mfa