1. Godel, Escher, Bach -- Because it sparked my interest and got me started down the path. 2. The Pragmatic Programmer -- a classic. Reminds me that I need to re-read it. 3. Effective Oracle by Design, by Tom Kyte -- Not that I use Oracle any more, thankfully, but really provided a lot of insight about how databases function and how it pays to deeply understand their internals when writing webapps.
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