Bit-player runs on WordPress software, currently version 3.4. The theme is built on Twenty Ten, one of the standard themes included in all WordPress distributions, but I’ve done a lot of tinkering. Another important software component is MathJax, the extraordinary JavaScript program that puts all of LaTeX’s math mode in a browser window.
I do most of my writing with Daniel Jalkut’s MarsEdit, rather than the built-in WordPress TinyMCE editor.
The web site is hosted on a virtual private server provided by Linode at an undisclosed location in Newark, New Jersey. The server operating system is Ubuntu Linux 12.04 (Precise Pangolin).
If you run into technical difficulty with the site, or have comments or questions, please send a note to brian@bit-player.org. (Backup address: bhayes@amsci.org.)