Here is another "minimum viable" blockchain implementation in Haskell: https://github.com/adjoint-io/nanochain https://github.com/adjoint-io/nanochain. It's a

Here is another "minimum viable" blockchain implementation in Haskell: https://github.com/adjoint-io/nanochain https://github.com/adjoint-io/nanochain. It's a bit simpler in implementation; the relevant data structures are defined a bit differently, so it could give a nice alternate perspective about what a blockchain written in Haskell may look like.