In Haskell and Elm! Nice project. I did not see any code "shared" (or Elm generated from the Haskell code) to enforce type-safety across the network barrier. Afaik there are a few projects that could help with this. Not saying you need this (small project, easy to manage) but it's very sweet to have type safety from db, through BE app layer, though the wire format, all the way to the FE model code.