1. I don't know about you, but in my experience there's plenty of new code to be written. Most of it falls squarely in the category of "Joe code" -- I don't spend my days implementing constraint optimization systems or Fibonacci heaps (sigh); rather, I write data munging scripts for in-house tools. CPAN modules help, but they don't do all that I need.

   So even reusing as much code as I can, I still have the chance to write plenty of code, and most of it's low level glue code, dealing with strings, hashes, refs, and regexes: Perl fundamentals. My coding style gets a good work-out, my Perl-slinging stays in shape, and I get a warm fuzzy feeling from all the wonderful code reuse.

2. There's plenty of existing code that hasn't been fully tested or debugged, or that's architecturally flawed. "Don't reinvent the wheel" doesn't necessarily apply when the wheel's more of an ellipse.

3. I do a lot of coding on my own time, where "maintaining productivity" isn't as great a concern as maintaining interest in whatever I'm doing, which usually means that I should spend more time writing code than figuring out what design pattern to follow with the dozen or so modules I can get off of CPAN.

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:wq