Giraffe is a fantastic little project that is a thin layer on top of ASP.NET Core. Works out of the box with the provided template, test locally, deploy to Azure, etc.
Thanks but I'm looking for something simple like returning plain text in 200 HTTP response using only built-in API. Completely minimal example. Using framework for me now would be like learning JavaScript by writing SPA in React.
FSSnip usually has those things. If you're talking that minimal I would just look up existing C# docs and translate them over to F#... ASP.NET Core is very lightweight w/ Kestrel though.