However, recently I discovered Halogen [0]. It is very similar to Elm Architecture, however, every component has its own _internal_ state, so you do not have to thread all state changes to the top-level component. It does this by existentially quantifying over the State [1].

Halogen is written in Purescript, which is a transpiler for javascript (yes transpiler, not compiler). Which means you basically get javascript semantics with a haskell typesystem + very good interop with JS, and no runtime system. The code purescript generates is actually readable. [2]

[0] https://github.com/slamdata/purescript-halogen/tree/master/d... [1] https://wiki.haskell.org/Existential_type [2] https://purescript.org/ [3] http://try.purescript.org