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Agile PHP Development Bookshelf
Extreme Programming Explained: Embrace ChangeExtreme Programming Explained: Embrace Change by Kent Beck
Buy new: £13.48 / Used from: £13.31
An essential starting point.
Agile Software Development with SCRUMAgile Software Development with SCRUM by Ken Schwaber
Buy used from: £26.98
Useful introduction to the basics of agile projects.
Essential PHP SecurityEssential PHP Security by Chris Shiflett
Buy new: £11.47 / Used from: £10.98
An essential, if lightweight, security primer that all PHP developers should read.
Advanced PHP Programming (Developer's Library)Advanced PHP Programming (Developer's Library) by George Schlossnagle
Buy new: £22.24 / Used from: £14.89
One of too few good advanced PHP books that get into the technical details.
Working Effectively with Legacy Code (Robert C Martin)Working Effectively with Legacy Code (Robert C Martin) by Michael Feathers
Buy new: £17.96 / Used from: £15.93
Clearly explains the use and usefulness of advanced development techniques.
Agile Estimating and Planning (Robert C. Martin)Agile Estimating and Planning (Robert C. Martin) by Mike Cohn
Buy new: £14.48 / Used from: £11.50
Well written and well-referenced guide that helps demistify one of the trickiest. aspects of software development
JavaScript: The Definitive GuideJavaScript: The Definitive Guide by David Flanagan
Buy new: £21.24 / Used from: £12.96
The only Javascript book that Crockford recommends, an absolute essential for any web2.0 developer.
Test Driven Development (The Addison-Wesley Signature Series)Test Driven Development (The Addison-Wesley Signature Series) by Kent Beck
Buy new: £14.98 / Used from: £3.99
Jumps between languages in a somewhat confusing fashion, but still a very good book for TDD.
PHP 5 Objects, Patterns, and PracticePHP 5 Objects, Patterns, and Practice by Matt Zandstra
Buy new: £26.59 / Used from: £16.94
Useful intro to objects & patterns - critically, it's PHP5 only rather than a confusing mix.
The Pragmatic ProgrammerThe Pragmatic Programmer by Andrew Hunt
Buy new: £15.91 / Used from: £12.97
The seminal guide to modern software development. Another good starting point.
Peopleware: Productive Projects and TeamsPeopleware: Productive Projects and Teams by Tom DeMarco
Buy used from: £73.95
Highly authoritative guide to the principles and psychology of development projects and teams.
Joel on Software: And on Diverse & Occasionally Related Matters That Will Prove of Interest etc..: And on Diverse and Occasionally Related Matters ... or Ill-Luck, Work with Them in Some CapacityJoel on Software: And on Diverse & Occasionally Related Matters That Will Prove of Interest etc..: And on Diverse and Occasionally Related Matters ... or Ill-Luck, Work with Them in Some Capacity by Joel Spolsky
Buy new: £11.25 / Used from: £12.00
Background rather than critical reading, but well worth it.
Smart and Gets Things Done: Joel Spolsky's Concise Guide to Finding the Best Technical Talent, Hardback: Joel Spolsky's Concise Guide to Finding the Best Technical TalentSmart and Gets Things Done: Joel Spolsky's Concise Guide to Finding the Best Technical Talent, Hardback: Joel Spolsky's Concise Guide to Finding the Best Technical Talent by Joel Spolsky
Buy new: £8.10 / Used from: £3.97
Read this before you hire another developer. Sound advice as ever from Joel.
Php|architect's Zend PHP 5 Certification Study GuidePhp|architect's Zend PHP 5 Certification Study Guide by Davey Shafik
Buy new: £18.99 / Used from: £28.24
The only guide to the rather tricky ZCE/5 certification. Proofreading is poor but the exam helps you round out your skills.
PHP|architect's Guide to PHP Design PatternsPHP|architect's Guide to PHP Design Patterns by Jason E. Sweat
Buy new: £13.49 / Used from: £12.23
A useful companion to the ZCE guide, although it also covers outdated PHP4 code.
JavaScript: The Good PartsJavaScript: The Good Parts by Douglas Crockford
Buy new: £11.61 / Used from: £8.70
Crockford has finally written his own Javascript book, and it looks to be excellent