Demo app that does OAuth integration for authentication and registration of user for multiple programming languages

We need expert developers to produce demo apps for us. You will need to know how OAuth works, and in the demo app, you need to integrate an OAuth service provide for authentication and user registration. The OAuth provider will be given in the chat, and you can read more about how their OAuth integration works at their docs page. Basically we need a simple, demo app with only the required web pages and code to demonstrate how the provider can be integrated in to an application written in a specific language such as Java, Node.js, C# etc. Currently we need the demo apps for the following languages Java (For spring boot) Node.js (For [login to view URL] and other major frameworks) C# (For ASP.NET) Python (For Django and Flask frameworks) Ruby (Rails framework) You will need to write the documentations page as well for this. In your bid, please mention what language and framework would you like to build the demo app for? you can mention multiple if you can do it.