It is a WordPress theme that I developed from scratch. It is minimalist, and that is mainly why I haven’t gone through the child theme approach.
Development wise, the blog is a work in progress and a base for experimental techniques. This is the way I like to do things when it comes to my own stuff. So in case it doesn’t display well on your IE6/IE7 or even IE8 browser, I advise you to switch to a more progressive culture. One that doesn’t tie a rope around your neck. However, I will be addressing these old browsers in my spare time.
The markup is mostly HTML5 new semantic elements, for which you will hardly find two persons that agree on the same way to markup structure for a certain content. For that reason, this area needs to be improved in the theme. I will keep re-thinking and adjusting as long as I keep discovering semantic holes in my markup (which might be useless at the end). If you want to have an idea of the struggle that is currently happening, read this article by Divya Manian. I advise you to read the comments to Divya’s article as well.
As for CSS, I am using normalize.css as a base start. It is basically an alternative to CSS resets and more inline with modern standards. You can also customize it for your own styles. I did tweak it a little bit myself.
For twitter updates, I use Remy Sharp’s twitter.js library.
The core? Should I tell you it is PHP? I think you already know: WordPress is written in PHP. So it is PHP plus MySQL at the back end.
As I said earlier, it will be a work in progress and a lab for research and experiments.