Date and DateTime are among the slowest classes in ruby's standard library. They are slow enough that they are often the bottleneck in any code that uses them. home_run is a new ruby library that provides fast Date and DateTime classes that are mostly compatible with the ones in the standard library. This presentation will discuss why the standard Date and DateTime classes are slow. It will go over previous attempts to speed them up. It will discuss the approach that home_run takes to make Date and DateTime fast, and the tradeoffs involved. There will be some discussion of the Ragel parsing library, C gotchas that may trip rubyists up, and how to write leak-free ruby extensions in C. Finally, it will discuss how home_run has affected the greater ruby ecosystem.