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Hi. I’m David. I’m a security geek. Mostly. Well, that’s my job, anyway. In real life, I like to program, goof around with network stuff, hunt for geocaches, watch movies, and other typical geek-like activities. Though I also have three kids, so really what I like most is making them laugh. Which is good, ‘cause that’s about all I have time for. :)

I started this blog because I do periodically have geeky ideas and ramblings that I’d like to share with others, and because my main personal site is so out-of-date that I have trouble even admitting it exists. (see aforementioned lack of time).

I hope you find the things I have to say useful, or at least, entertaining. Feel free to throw virtual Shmooballs at me on Twitter (@DarthNull), but be warned, I have access to a pretty strong rebuttal mechanism! If you’d like to talk in more than single-sentence fragments, my email is david (at) dasnet (dot) org. You can find my PGP key on Keybase, and at the MIT PGP Keyserver.

About the Site

I’ve been playing with websites and blogs and such for quite a while now. First it was static files built from XML sources. Then I self hosted a couple sites using Drupal for a while. I eventually got tired of how complicated that was, and moved to self-hosted Wordpress, then in 2010 I moved to a Wordpress.com hosted site. Then I kind of went back to the beginning, with a static site built from simple files (this time around, it’s built using Markdown instad of XML). For a few years (2014-2017), I used a system based on Second Crack, originally built by Marco Arment. I made a few tweaks, to support a couple different taxonmy structures (lists, as well as tags), but never really went too much further with it. And the overall style was pretty much a direct lift from Marco’s blog, as well – which I liked, because it was simple and straightforward… But eventually I realized it still needed some work.

Which brings us to today – a new and improved version of the site. I’m still trying to keep the overall look simple – with a header that’s still inspired by marco.org but with some extra features. You can read everything in the “Everyting” section, or you can also focus on specific areas of interest, so perhaps those who are interested in puzzles but don’t care about the infosec community can just bookmark the Puzzles and Fun section of the site and ignore everything else. It’s also built using a new system - Hugo. Just like Secondcrack, it very quickly builds a static site, complete with home and sectional pages and tags. But it natively supports multiple, arbitrary taxonomies (so I can have lists, and “series” posts, and just anything else I like). It’s also got a pretty strong templating system, which makes building out the theme much easier.

The site doesn’t have comments (I never got many anyway). RSS feeds are available – most any time you can fetch a page using .html, just add .xml instead (for example, http://darthnull.org/rss.xml for a feed of the main site, or http://darthnull.org/tag/puzzles.xml for a feed of posts tagged “puzzles.")

You can also follow this blog on Twitter. New posts will be tweeted out by @NullBits

About the Content

In addition to my (frequently overdue) efforts to document various crypto puzzles and contests, I try to write about things that I’ve found interesting, neat tricks I’ve discovered or built, bugs I’ve found, and occasionally some crazy ideas. I’ve added a few details to the Second Crack system: in particular, support for cross-posts (local copies of posts I wrote for my employer’s site), references (so I can have a good place for talk slides, white papers, etc.), and lists (basically, special categories which serve to collect specific items together, like a list of all presentations, for example).

You can find tags/categories, lists, and post types all collected on the Topics page.