As a non-Haskeller, the only tool I can think of interacting with that has any Haskell is Hasura's graphql-engine[0], which GitHub stats say is 28% Haskell (and then like 55% web languages, so I assume the backend is all Haskell and the web languages are for the UI it presents etc)
Are there other popular Haskell tools? Or is it more of an academic language? I was surprised to see it on the GitHub repo.