Drupal Developer Days will feature sprints that run from Monday, March 24, to Sunday, March 30, 2014, where like-minded Drupal developers will meet, discuss and build together to fix issues and (among other things) help bring Drupal 8 closer to release. Given the need for attention on Drupal 8 critical issues and release blockers, we will heavily work on core, but there are several other topics to join as well that don't even require coding skills. It is amazing what can happen when we bring everyone together!
Previous years' sprint topics included Multilingual, Views, Mobile, Configuration management, Theme system, WSCCI, Field API, Project applications, Documentation, Accessibility, User experience.
Coding experience is not required to participate on most of these sprints, several sprints welcome people testing changes, writing text, making suggestions, and so on. Sprints are not about Drupal 8 only, although many will focus on Drupal 8.