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RailsBrain: Fast, AJAX-powered Rails documentation

By Peter Cooper / May 7, 2007


Rails documentation sites are almost ten a penny, but today I was surprised by a new site called RailsBrain. RailsBrain takes the usual "list of methods down the left" approach, but couples it with some nifty AJAX and (so far) a very quick server to serve up the docs in record time.

Being in Europe, I usually notice a couple of seconds here and there when loading pages, but RailsBrain is scarily quick at delivering pages when I click on a method name. Furthermore, RailsBrain makes it a lot easier to find the method you need to documentation for with a "live search" type effect in the left hand box. This definitely replaces for me in the short term.

(Note: If you're already using GotAPI, this isn't likely to interest you, as what it offers is no better, but is just easier to use on the quick.)


  1. dmauldin says:

    Wow! This is awesome. Totally love it.

  2. Matthew says:

    This makes looking for methods and classes so much easier than the current API. I'm glad I found this post about RailsBrain.

  3. court3nay says:

    this is neat, look great, but it's a terrible example of ajax.

    Most of the time when using the API there are a few things I want to do. Mainly, I'm either looking for information (navigating) or sharing a method with someone I'm helping (on IRC or otherwise).

    Navigation. It's fast, but there's no BACK BUTTON. This is the failing of over-eager ajax development. People moan about frames, but they're a zero-skill way of maintaining history.

    Sharing. I want to link to a method directly, or even bookmark it. Every link in this app is "#". This could be fixed by the developer by actually linking to the method directly and then using an onclick to capture the click.
    This would probably also allow users to open links in new tabs.

    These are all possible to do with ajax, and examples without them cast a bad light on rails in general.

  4. Brian Chamberlain says:

    Hi all,
    My thanks to the people at RubyInside (a site I read on the regular) for posting an article about my pet project. I'm glad some of you have found it useful.
    I'm not going to get into a discussion of the proper use of AJAX here since I think the whole web community is trying to figure that one out...still. I will say that the project is still under development. I've recieved some great feedback from a lot of people (especially from the people in my local ruby group and I'm going to be incorporating those ideas into the next version, which should be out soon.
    Yes, it will have back button support...and maybe even bookmarks!

  5. Jerrett says:

    GotAPI is actually quicker to use if you use - and it will go through Ruby Core, STDLIB, and Rails docs :)

  6. David Berube says: is pretty slick; it's PHP style documentation, so you can type into your location bar to get docs on the render method.

    Take it easy,


  7. James H says:

    Brain, if you're still reading this thread you should know the "about railsbrain" link is giving me a 404. I was hoping to find an email address on there to show you a style issue (scrunched text) I have with RailsBrain using FF 2.0.

  8. Logan Koester says:

    I second Jerrett's recommendation of GotAPI, mainly because it also includes documentation for JQuery, HTML, CSS, Javascript etc

  9. Ruby on Rails examples says:

    It is so cool. I really live it.
    The one on rubyonrails uses frames and it is very hard to surf.

    Thanks a lot!

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