Clojure provides a nice, consistent interface for logging via clojure.tools.logging (one of the new, modular contrib libraries). It automatically wraps slf4j, commons logging, log4j and java.util.logging but you can override the implementation, if needed. At World Singles, we wanted to log some levels to a data store (initially MySQL, but later on to MongoDB) so we needed to write a custom log appender. I talked a bit about writing a custom log4j appender in Clojure in an earlier blog post but didn't go be[...]