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I’m not the author of this, but it’s a relatively new tool to turn F# into javascript. It uses Babel to do so.

Works directly on F# source code, no compilation to .NET bytecode needed. Optimizes F# code to generate as clean JavaScript as possible. Passes location data to Babel to generate source maps. Compatible with all Babel plugins and other JS development tools, like Webpack. Support for most of the F# core library and a bit of .NET Base Class Library. Tiny core library included (around 20KB minified and gzipped) with no runtime. Organizes code using ES6 modules. Interacts seamlessly with other JavaScript libraries. *Bonus: compile NUnit tests to Mocha.