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The latest version of the book is B4.0, released 2 months ago. If you've bought a PDF of the book and would like to update it to this version (for free), visit your home page.

By default this page displays the errata for the latest version of the book. If you have a previous version, select it here:

If you've found a new error, please submit it.

  • Typo
  • Tech. error
  • Suggestion
  • Maybe next edition
  • Not a problem
  • Reported in: B4.0 (09-Apr-20)
Paper page: 9
It doesn't actually say it anywhere there, but in order to get yarn running, you'd need to install node.js and npm install yarn. Otherwise you get ...more...
  • Reported in: B4.0 (11-Apr-20)
PDF page: 14
Paper page: xii
The setup process probably requires some work. Running ruby bin/setup for introduction / 01 stops with multiple problems. There are simple things li...more...
  • Reported in: B4.0 (16-Apr-20)
PDF page: 44

In the package.json section you reference a library called “actionstorage”. I believe you meant *active*storage. --Julian Pinzon Eslava

  • Reported in: B4.0 (23-May-20)
PDF page: 72
On page 72, near the bottom, we are told to include <%= stylesheet_pack_tag("application") %> in layouts/application.html.erb. It stands to reason tha...more...
  • Reported in: B4.0 (17-Apr-20)
PDF page: 162

It should be @status not status. I couldn't update the seats without changing that--André Furquim Xotta

  • Reported in: B3.0 (22-Mar-20)
PDF page: 197
Paper page: 189
The code snippets moving forward are probably from the wrong chapter, that is, /server rather than /state. The text says things like "It’s just cal...more...