I'm happy to announce the first, experimental version of the time-lens library. http://hackage.haskell.org/package/time-lens https://github.com/feuerbach/time-lens Its goal is to simplify working with time and date data structures in Haskell by providing lens-based overloaded accessors for Data.Time types. E.g. to find the current hour you currently need to write something like todHour . localTimeOfDay . zonedTimeToLocalTime <$> getZonedTime With time-lens it becomes getL hours <$> getZonedTime The difference is even more impressive when you need to *update* the hour in a ZonedTime structure, but admittedly such a need is relatively rare. The library is pure Haskell 2010 code. It is also completely type-compatible with Data.Time, so it's very easy to start using it in existing projects. -- Roman I. Cheplyaka :: http://ro-che.info/