Agile web development with rails by david heinemeier

Beta
Book
Agile publishing for agile developers
Under Construction The book you’re reading is still under development. As
part of our Beta book program, we’re releasing this copy well before a normal
book would be released. That way you’re able to get this content a couple of
months before it’s available in finished form, and we’ll get feedback to make
the book even better. The idea is that everyone wins!
Be warned. The book has not had a full technical edit, so it will contain
errors. It has not been copyedited, so it will be full of typos and other weirdness.
And there’s been no effort spent doing layout, so you’ll find bad page
breaks, over-long lines with little black rectangles, incorrect hyphenations,
and all the other ugly things that you wouldn’t expect to see in a finished
book. We can’t be held liable if you use this book to try to create a spiffy
application and you somehow end up with a strangely shaped farm implement
instead. Despite all this, we think you’ll enjoy it!
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Thank you for being part of the Pragmatic community!
Andy & Dave
Prepared exclusively for Anton Fonarev
Agile Web Development with Rails
Fourth Edition
Sam Ruby
Dave Thomas
David Heinemeier Hansson
with Leon Breedt
Mike Clark
James Duncan Davidson
Justin Gehtland
Andreas Schwarz
The Pragmatic Bookshelf
Raleigh, North Carolina Dallas, Texas
Prepared exclusively for Anton Fonarev
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Copyright © 2011 The Pragmatic Programmers LLC.
All rights reserved.
No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any
form, or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the
prior consent of the publisher.
Printed in the United States of America.
ISBN-10: 1-934356-54-9
ISBN-13: 978-1-934356-54-8
Printed on acid-free paper.
B13.0 printing, February 2, 2011
Version: 2011-2-2
Prepared exclusively for Anton Fonarev
Contents
Changes in the Beta Releases 10
Beta 13 — February 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Beta 12 — January 10 . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Beta 11 — November 24 . . . . . . . . . .