We support a variety of languages (https://www.hackerrank.com/environment) Can you tell me which examples you're talking about?
If you have any questions about setting it up, send a message to the `fsharp-opensource` group (https://groups.google.com/forum/?fromgroups#!forum/fsharp-op...) and we'll provide whatever help you need.
And if you guys do add F# support, send out a tweet with the `#fsharp` hashtag -- many F#'ers watch that hashtag for F# news/announcements.
I am interested in using Javascript fyi.