@cgenie spotted a bug I have introduced as part of !415 (merged) . In particular, the extractNgramsFromDocument function is catching all exceptions, and it's doing so using Control.Monad.Catch and not Control.Exception.Safe, which means that it will intercept things like the KillWorkerSafely exceptions being thrown when we hard-quit the server with ctrl^c.

I think that extractNgrams should be given the ability of throw a specialised exception (like NgramsExtractionException or similar) that can be used to wrap any HttpException in the implementation of the main instance, so that we can catch the correct exception, leaving the other be.