In the 70s and early 80s, along with Mike Alexander, Victor Berman, Mark Hersey and Fred Swartz, Jack O’Keefe was team member and chess consultant of the program CHAOS  , at that time affiliated with the Computing Center of the University of Michigan. CHAOS was one of the strongest programs of its time, using an unique, knowledge based and selective best-first, iterative widening approach , keeping the search tree in memory.
The biggest and most powerful computers do that very well. In one second, they can examine thousands of possible moves. The problem is, they stop to consider lousy moves that a human player wouldn't waste a fraction of a second on. On the other side of the fence are the slower but "smarter" computer programs. They can't think about zillions of chess moves, so they need a lot of information about chess plugged into them. CHAOS is one of these latter, pumped with chess information from John J. O'Keefe, one of Michigan's top players.
- Photograph contributed by Carla Campbell, from Chess Note 5708. Jack O’Keefe (1930-2008) by Edward Winter
- John O'Keefe's Obituary by Ann Arbor News
- Norman Tweed Whitaker and the Search for Historical Perspective: A Tale Full of Genius and Devil by John S. Hilbert from Chess Archaeology
- State Champions from Michigan Chess Association
- Chaos' ICGA Tournaments
- The Eleventh ACM's North American Computer Chess Championship as pdf reprint from The Computer History Museum
- Computer vs. computer: Duel on the Chessboard, Boca Raton News - November 27. 1979 from Google News on ACM 1979