Cascalog is a data processing library for Clojure for processing Big Data on top of Hadoop or doing analysis on a local computer from the REPL. Cascalog is inspired by Datalog and blends logic programming with functional programming. Cascalog's power comes from its nature as a library for Clojure (instead of being a custom language like SQL or Pig). This gives Cascalog amazing capabilities for abstraction and composition. After you learn Cascalog, you wonder how you ever did data processing any other way.