Matchcraft, founded in 1998, is a technology driven media solutions company that maximizes Return-On-Investment for interactive advertisers. Matchcraft tracks, analyzes, and optimizes the “matches” to maximize results. We are a very large user of Google and Overture paid ads and their respective API’s.
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9 Jobs at ITA Software that mention Lisp.

Lisp is just one of the many “technological requirements” for this position, but I know some of the people in these labs, and it would be a good place to work, probably with lots of freedom to choose how you do things. In Chicago or Palo Alto.

(Whatever that is).  “Service Optimization Developer, IT, Common Lisp, Java, Prototyper.” In Los Altos, CA.
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Three jobs posted here. This one mentions Lisp.

Senior Software Engineer, Ingenuity.
Development team for Ingenuity development platform (used for developing enterprise knowledge management applications) and high-availability, high-volume, web-based scientific applications.

Senior Developer, Chrysalis
“A big plus if you are skilled in Scheme or Common Lisp.”. Via Dice.

Senior Research Scientist, Lockheed Martin