Ignore the counter above, the timeframe is from February 29 to March 8 in your timezone, pick a 7 day block to work within these dates.
Roguelikes are traditionally procedurally generated RPGs in the mould of Rogue, with turn-based interactions in a grid-based environment, where levels are procedurally generated each play-through and death is permanent.
In 2005, the roguelike community established a yearly event, the 7DRL Challenge, in which developers are challenged to create a roguelike in seven days. This allows one to have the shared misery of knowing you are not the only one tracking down a bad pointer at the 167th hour. The annual event occurs during a week in early March.
7DRL Challenges are NOT about being a fast coder, but rather proving you can release a finished, playable roguelike to the world. There is no winner of the challenge, but rather all those who finish are honored for their work, the criterion is completeness.
There are many interpretations of what a roguelike is which may serve as a guidance. However 7DRLs may bend of even break these interpretations in the name of Innovation.
How to participate
To date, there have been fifteen annual 7DRL challenges.