Interactive development tool that makes it easy to develop and debug Elm programs.
elm/compiler
In 2013, Laszlo Pandy figured out how to make a reliable Time Traveling Debugger for Elm. It became part of
elm-reactorin 2014 thanks to Michael James who adapted it for how we thought people would work with it in practice. Since then (1) the internal implementation of Elm has changed a decent amount and (2) we have learned a lot about what production users need to use this tool seriously. So time travel is not available in
elm-reactorright now, but it will be coming back with a new design focused on real workflows. I think this will lead us to a tool that is both more reliable and more broadly useful whether you are making games or web apps.
Debugmodule still makes it easy to peek at values in your program.