It's often very difficult to come up with one, because there isn't really a silver bullet here. The draw to F# for me, when I was learning it, was I needed to

It's often very difficult to come up with one, because there isn't really a silver bullet here. The draw to F# for me, when I was learning it, was I needed to build a DSL in a large system I was working on (side note: there must be a law somewhere stating that any large system will have a DSL in it somewhere). I didn't know about libraries like FParsec or anything (or a C# equivalent), so I just googled "how to write a DSL C#" and ended up somewhere showing F# code. I was curious. A week later, I wrote the whole thing in F#, with tests, and all requirements were fulfilled. Upon re-writing in C# (because reasons...), I had to re-think the problem. I used F# types and pattern matching everywhere, and Active Patterns to make stuff really concise and readable. A lot of the branching logic in my C# rewrite didn't really exist in F# because of this, and it was really hard for me to track down how everything worked in C#. I'm still convinced that someone unfamiliar with F# could understand the F# version better than the C# version because of how much less code and branching logic was involved. For a more professional case study, Microsoft Security Risk Detection is a fuzz testing service written in F#: https://blogs.msdn.microsoft.com/dotnet/2016/12/13/project-springfield-a-cloud-service-built-entirely-in-f/ https://blogs.msdn.microsoft.com/dotnet/2016/12/13/project-s... We blogged about their experience, and they do have practical examples there.