I want to enable a Haskell benchmarking bot that would upload its data to a Google Fusion Table each time it runs.  That seems to require the "service-to-service" mode for Google's OAuth2:

   https://developers.google.com/accounts/docs/OAuth2ServiceAccount

There are a bunch of libraries on Hackage for different flavors of OAuth.  But I haven't yet found one that handles this signing of JWT headers and claimsets.  Is there something I'm missing?

Thanks,
 -Ryan