The idea is to use the F# language for writing both client and server-side part of the web application, to develop client-side code in a type-safe programming language using a subset of the F# library, and to provide a way to write both server-side and client-side code as a part of single homogeneous module defining the web page logic. It includes a first translator from an ML-family functional language to JavaScript. The concept is described in the paper Tomáš Petříček Don Syme. AFAX: Rich client/server web applications in F#, there is a tutorial like introduction and there is some upcoming software.