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The software equivalent of a tool-and-die specialist; one who specialises in making the tools with which other programmers create applications. Many hackers consider this more fun than applications per se; to understand why, see uninteresting. Jon Bentley, in the "Bumper-Sticker Computer Science" chapter of his book "More Programming Pearls", quotes Dick Sites from DEC as saying "I'd rather write programs to write programs than write programs".