Probably the most commonly known kata in the coding dojo and retreat 'scene'. We choose this one to start running on as big as possible known ground.

Conway's Game of Life

The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970. The "game" is a zero-player game, meaning that its evolution is determined by its initial state, requiring no further input. One interacts with the Game of Life by creating an initial configuration and observing how it evolves.

Why One Kata For All Locations?

The global day of code retreat was nearing and since we really liked the idea and wanted to join we started discussing if we shouldn't do something like that just for us web developers. So we can learn more and just practice only on JavaScript ... and from there it started. Out of a simple local event this evolved, let's see what it becomes.
Martin and me we sat together and discussed what we think could be a cool format for this code retreat and what we think could and should be done to enhance the experience and get even more out of it for us web developer.
After some forth and back we thought of the following:

1. A pure JavaScript Code Retreat
2. All locations working on the same code (a Kata we have to find together before)
3. All locations do the same exercises on that code
4. Joined retrospective after every session across all locations (that will be the fun part I guess)