The earliest memory I have of ‘programming’ is in the early/mid 90s when my father brought home a computer from work. We could play games on it … so of course I took the spreadsheet program he used (LOTUS 123, did I date myself with that?) and tried to modify it to print out a helpful message for him. It … halfway worked? At least I could undo it so he could get back to work…

After that, I picked up programming for real in QBASIC (I still have a few of those programs lying around), got my own (junky) Linux desktop from my cousin, tried to learn VBasic (without a Windows machine), and eventually made it to high school… In college, I studied computer science and mathematics, mostly programming in Java/.NET, although with a bit of everything in the mix. A few of my oldest programming posts on this blog are from that time.

After that, on to grad school! Originally, I was going to study computational linguistics, but that fell through. Then programming languages (the school’s specialty). And finally I ended up studying censorship and computer security… before taking a hard turn into the private sector to follow my PhD advisor.

Since then, I’ve worked in the computer security space at a couple of different companies. Some don’t exist any more, some you’ve probably heard of. I still program for fun too, and not just in security.

But really, I still have a habit of doing a little bit of everything. Whatever seems interesting at the time!

Generating YouTube user RSS feeds

2015-05-11

On 4 March 2014, YouTube deprecated the v2.0 API for YouTube (source). One of the unfortunate side effects was that RSS feeds for user uploads were included in what was deprecated.

Previously, you could get an RSS feed with a link of the form: https://gdata.youtube.com/feeds/base/users/{user}/uploads For the longest time, even after the deprecation, those links still worked, but a couple weeks ago, more and more of the video feeds I was subscribed to started redirecting to YouTube Help account. As thrilling as that channel is, it’s not what I’m looking for.

Let’s fix it.

Tupper's self-referential formula

2015-05-07

Quick post today. Let’s implement Tupper's self-referential formula in Racket!

\frac{1}{2} < \left \lfloor mod \left ( \left \lfloor \frac{y}{17} 2^{-17 \lfloor x \rfloor - mod(\lfloor y \rfloor, 2)} \right \rfloor, 2 \right ) \right \rfloor

(tupper 960939379918958884971672962127852754715004339660129306651505519271702802395266424689642842174350718121267153782770623355993237280874144307891325963941337723487857735749823926629715517173716995165232890538221612403238855866184013235585136048828693337902491454229288667081096184496091705183454067827731551705405381627380967602565625016981482083418783163849115590225610003652351370343874461848378737238198224849863465033159410054974700593138339226497249461751545728366702369745461014655997933798537483143786841806593422227898388722980000748404719)

That’s the result of graphing the above function at a point rather far away from the origin. Specifically, where y is around that crazy big number. Look familiar?

It's all Greek to me

2015-04-17

A few days ago an interesting article came across my RSS feeds: It’s All Greek (or Chinese or Spanish or…) to Me. Basically, in English, when you’re confused, you’ll often say ‘It’s all Greek to me’. It turns out that man (if not all) languages around the world have a similar saying, but the target varies. Luckily, Wikipedia has a lovely page about it: Greek to me.

A Quick Look at RC4

2015-04-14

In cryptography work, RC4 (Rivest Cipher 4) is well known as both one of the easiest to implement and fastest to run symmetric encryption algorithms. Unfortunately, over time there have been a number of attacks on RC4, both in poorly written protocols (such as in the case of WEP) or statistical attacks against the protocol itself.

Still, for how well it formed, it’s an amazingly simple algorithm, so I decided to try my hand at implementing it.

Generating perfect portmanteaus

2015-04-07

A quick programming post, since it’s been a while, inspired by this video:

I’m not going to go quite as far as that, but I thought it would be interesting to write up some quick code to generate portmanteaus¹.

Performance problems with Flask and Docker

2015-04-03

I had an interesting problem recently on a project I was working on. It’s a simple Flask-based webapp, designed to be deployed to AWS using Docker. The application worked just fine when I was running it locally, but as soon as I pushed the docker container…

Latency spikes. Bad enough that the application was failing AWS’s healthy host checks, cycling in and out of existence¹:

Parsing AWS instance data with jq

2015-04-01

Semi-random amusing code snippet of the day:

aws ec2 describe-instances | jq << EOF
    .[][].Instances[]
    | select(.Tags[]?.Value == "production")
    | .PrivateIpAddress
EOF

gif shrinkage with ImageMagick

2015-03-05

I have a gif collection now. :)

ts: Timestamping stdout

2015-02-26

Loving data as much as I do, I like to optimize things. To make sure I’m actually going the right way, it’s useful to time things. While it’s trivial in most languages to add timing, it’s even easier if you don’t have to.

update-dotfiles encryption

2015-02-11

I do like having my dotfiles on GitHub. For one, it means that they’re always available when I set up a new machine. For two, others can see them and take whatever is interesting for their own dotfiles. But all that has a disadvantage: what if I want to store my SSH configs?