The Cult of the Bound Variable: The 9th Annual ICFP Programming Contest

The annual ICFP Programming Contest has become one of the premiere programming competitions in the world. The 9th incarnation of the contest, “The Cult of the Bound Variable,” was held in July 2006 and organized by the Principles of Programming group at Carnegie Mellon University. This report details the contest tasks, the technology used to produce the contest, and the contest results. Several tasks draw ideas from programming languages research. For example, participants implemented a simple virtual machine, played an adventure game based on a substructural logic, and programmed in a two-dimensional circuit language with a discordantly high-level operational semantics. The contest technology includes an optimizing compiler for a high-level functional language that targets our virtual machine. By the end of the three day contest, 365 teams, composed of 700 programmers from all over the world, solved at least one of the contest tasks.