Most A/B testing solutions, including Visual Website Optimizer, fall into a category known as client-side testing. What “client-side” means is that a variation of your test page is created (before displaying to the visitor) by doing manipulations on the browser using clever JavaScript. Your web server always sends the same default version of the page as it would normally do. Since the changes needed to display a variation happen on visitor browser (and not your server), this technology is called “client-side”.
There is another breed of testing frameworks known as “server-side” A/B testing. Using such frameworks, no modification happens on browser level. In fact, when the browser requests your page, a randomly picked version of your test page is sent from your server. While this means you need to involve your developers for implementing changes in your website code, it does give you unlimited flexibility of testing.
The server-side A/B testing framework for PHP that we officially support is (unsurprisingly) called phpA/B . It’s free to use (for personal websites). If you know PHP, see the documentation for this library. Just as VWO appeals to marketers because it lets them do A/B testing without making any code changes, we are sure phpA/B will appeal to developers who prefer to dive into code. The library provides integration with Google Analytics out-of-the-box. It also filters out all bots and shows them your control page so that it doesn’t affect your SEO efforts. If you are a Ruby on Rails developer, you may be interested in A/Bingo or Vanity.
Why are we supporting server-side testing frameworks? Aren’t they in competition with us? Not really! Our focus with Visual Website Optimizer is to make A/B and multivariate testing easier by taking technical hassles out of the picture. In fact, ideally, we want our users never to touch any code (be it HTML, JavaScript, CSS or PHP). So, VWO is suited for people who don’t want to rely on developers or IT team for doing even the simplest kind of testing (thereby lengthening the time involved in getting the test up and running).
On the other hand, server-side testing frameworks such as phpA/B are better suited to companies which want to tightly integrate A/B testing in their development process. This is in line with the upcoming “lean-startup” or “test-driven-development” scene.
Different companies, different needs, different A/B testing solutions! We hope you find the best fit for your needs.
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What I’m curious about is if there is any way I can determine what test is running by the user’s cookies, which are accessible from the server-side?
If I had a variation ID of 13, I could wrap some conditional views with an “if (Testing::getVariation() === 13) { … }”, which would be pretty sweet
Comment by Eric Clemmons — August 17, 2010 @ 12:41 am
Hi Eric,
I created phpA/B, and I think that’s a great idea! I have a way to call out the current variation in {phpab} tags but not using PHP. I’ll implement soon and update the version.
Cheers!
Brian
Comment by Brian Cray — August 18, 2010 @ 12:59 am