[chowells]

You can compile haskell programs with type errors (in GHC, anway) if you want. They crash when you attempt to execute code that has a type error, but if that's what you want, feel free to use it.

It's not something I've ever needed. It's got little to do with quickly exploring design space.

Edit:

I guess I should include a couple words about why it's not really necessary in real coding. A side effect of good module boundaries is that you can test breaking changes in isolation in the REPL. Change a few things that are tightly coupled at the same time, load their module, don't worry about fixing any other modules until the first one works the way you like. In practice, this means you almost never need the option to defer type errors to runtime.