Preloading Ajax data as JSON has helped improve the load time and perceived performance of our family software application. Most of the pages in our web client are dynamically generated in the browser from a complex set of JavaScript and CSS, so we're always looking out for ways to make them appear more quickly.

More at the Cozi Tech Blog.

I formed a Bike to Work team at Cozi. More at the Cozi Connections Blog

I find it useful to have multiple Firefox profiles for developing and testing. A clean profile for testing allows you to replicate most users' environments, who don't install extensions. Running a development profile in a separate profile lets you restart the browser without messing with your default environment. You can also run Firefox 2 and Firefox 3 side-by-side in separate profiles.

More at the Cozi Tech Blog.

It's not at all obvious how to use Visual Web Developer 2008 Express Edition to debug JavaScript in Internet Explorer. So I wrote it up at the Cozi Tech Blog.

The JavaScript engines in Firefox 2 (Windows) and IE6 can't handle the new Daylight Savings Time rules in the U.S. The Date() function returns a value that is off by an hour if the system time is between the second Sunday of March and the first Sunday of April.

More at the Cozi Tech Blog.

Update 2008/03/14: Mea culpa. This is not a widespread problem. It is caused by the presence of set TZ=PST8PDT in my C:\AutoExec.bat. Per KB932590, the existence of the TZ environment variable will cause the CRT to use the old DST rules. (I can't remember why I set TZ several years ago. It's part of the accumulated mess of files that I bring everywhere with me.)

Over at Cozi, we've started a new technical blog. I just put my first post up, describing a nasty problem we had late last year.

Here's the summary:

Internet Explorer 6 does not support transparency in PNG images. The best-known solution is to use the DirectX AlphaImageLoader CSS filter. It's less well known that using AlphaImageLoader sometimes leads to a deadlock in IE6. There are two workarounds. Either wait until after the image has been downloaded to apply the filter to the image's style, or use the little-known transparent PNG8 format instead of the filter.

More here.

Miscellaneous links.

• Via Dilip, the epic struggle between an animation and its animator.

• Sparky gets himself tasered. Deliberately. Geesh!

• We at Cozi partnered with Whirlpool to produce an edition of the Cozi software running on a fridge. It has been demonstrated at this year's CES (Consumer Electronics Show), where it's getting favorable reviews. Dory Devlin likes it. Watch Walt Mossberg talk about it too.

My first project at Cozi is to build a simple REST-style Web Service. Nobody here has done that before.

The first thing that I'm trying to get going is a simple URL rewriter, using an ASP.NET HttpModule.

I'm running Vista as my development desktop for the first time. So far, not bad, but there are lots of new quirks to get used to. I've been a good boy so far and I've left the User Access Control stuff enabled, so that I'm not running with administrative privileges by default.

It's my first exposure to IIS 7. I must say that the IIS UI is much improved (a low bar to surmount).

My first problem was that Skype was squatting on port 80, preventing browser requests going to localhost. This happens to me about once a year on a new dev machine, and I always forget.

To get the HttpModule going, I had to follow Mark Rasmussen's detailed instructions on making URL rewriting on IIS 7 work like IIS 6. The code will be deployed on Windows Server 2003, so IIS 6 compatibility is more important to me than IIS 7 purity.

I was trying to get some debug output appearing in DebugView, but my Trace.WriteLines were not showing up. Some Googling eventually showed me that I had to enable Capture Global Win32, which I never had to do before. Presumably because ASP.NET is executing in a different desktop session.

Cozi is the PC Mag Site of the Week.

This is the collaboration application to have for organizing your family life. It has simple, intuitive functionality that suits its family target audience perfectly.