Haste
A GHC-based Haskell to JavaScript compiler
... of Vagrant, VirtualBox, GHC sources and other black magic. Concurrency and MVars with Haste.Concurrent. Unboxed arrays, ByteArrays, StableNames and other low level features. Low-level DOM base library. You have three options for getting Haste: installing from Hackage, from Github or from one of the pre-built binary packages.