On the server side, is Duo deployed at the IdP or the SP?
Actually, you can choose how best to deploy Duo in your environment. At the SP, Duo Web supports client libraries for Python, Ruby, Classic ASP, ASP.NET, Java, PHP, Node.js, ColdFusion, and Perl. At the IdP, Duo provides a custom login handler for Shibboleth IdP 2.3.5.