F# that transpiles to Javascript! Wait, what? While at NDC is Oslo, Carl and Richard chatted with Tomas Petricek about the Fabel project, combining F# and the Babel project to turn F# into some tight Javascript code. Tomas talks about the easy parts of Fabel first, because Javascript does have some functional elements, and it is possible to write immutable-style code in Javascript if you really want to. Then come the more difficult parts, like typing. There's a judgement call to make about what makes sense in Javascript and what doesn't. But with the choices in where to run Javascript, writing in F# offers some interesting possibilities!