DotNetOpenAuth - DotNetOpenAuth is a free-to-use compiled library that comes with the real support to your site visitor to login with the help of openIDs via getting control of the ASP.NET control onto the page.
Procore - Procore is the world's most widely used construction project management software. Easy to use, mobile platform with unlimited user licenses.
ASP.NET SAML - ASP.NET SAML is an open-source authentication utility that has been used for exchanging authentication and authorization data between the channels.
CoConstruct - CoConstruct's project management software helps custom builders & remodelers coordinate projects, communicate with clients & crew, and control.
IdentityServer - An open-source, standards-compliant, and flexible OpenID Connect and OAuth 2.x framework for ASP.NET Core
BuilderTREND - Buildertrend is the #1 construction management software and construction app for home builders, remodelers, specialty contractors and commercial construction.