Performance in OpenSim

Jun 17, 2020

Yay, I have a new job! I’m now an Open-Source Software Developer at TU Delft, where I’m going to be working on biomechanical simulation software.

Why do I mention this? Because I’m initially tasked with trying to make OpenSim faster, which is something that beautifully ties together a few of my loves (research software, systems development, and low-level perf optimizations) with a few of my hates (software written by researchers, C++, and diagnosing cache misses) and I’ve been wanting to learn+write about performance for a while.

TextAdventurer: Rust Edition

May 9, 2020

Just as a little fun, I decided to rewrite textadventurer in Rust, source).

The server was initially written in ~600 LOC of Java with a basic websocket library. The Java implementation worked fine–it was essentially just a tiny tech demo to demo a jobson feature–but I decided to rewrite it in Rust so I could understand where the pain-points are in an application like this.

Jobson 1.0.0

Nov 5, 2018

After many weekends and evenings of fixing little bugs, cleaning up the codebase, and polishing the build, I’ve finally managed to publish v1.0.0 of jobson.

I open-sourced jobson late November 2017. The version I demoed here was already close to release-grade in terms of implementation (the server had >200 tests, was used in prod, etc.). However, the deployment, installation, documentation, and maintenance needed work.

Side Project: Rust: fo2dat

Jun 26, 2018

tl;dr: I used Rust to make this CLI utility for extracting Fallout 1+2 DAT files.

I love the occasional playthrough of Fallout 1 and 2. They were some of the the first “serious” games I played. Sure, DOOM/Quake/Command & Conquer were also “mature”—I played them around the age of ~10, which marked me as doomed (heh) by the kind of adults that would also think eating sweets is a surefire path to heroin addition or something—but F1+2 included prostitutes, drugs, slavery, and infanticide: irresistibly entertaining topics for a teenager.

Integrating Software

Apr 26, 2018

tl;dr: If you find you’re spending a lot of time integrating various pieces of software across multiple computers and are currently using a mixture of scripts, build systems, and manual methods to do that, look into configuration managers. They’re easy to pick up and automate the most common tasks. I’m using ansible, because it’s standard, simple, and written in python.

Research software typically requires integrating clusters, high-performance numerical libraries, 30-year-old Fortran applications by geniuses, and 30-minute-old python scripts written by PhD students.

(Not so) Fancy-Pants new Website

Mar 10, 2018

So, I just spent an evening + morning refactoring the site into a, uh, “new” design.

I only ocassionally work on this site these days—I now see it as the sparse journal of a madman that also likes to distribute mobile-friendly versions of his CV—but I thought it would be a nice and easy blog post to reflect on how the site has changed over the last 3 years.

The original version of adamkewley.com was launched in May 2015 and was the fanciest design:

State Machines in ReactJS

Jan 6, 2018

I’m currently implementing job resubmission in Jobson UI and found that state machines greatly simplify the code needed to render a user workflow.

Cheeky Hackers

Dec 15, 2017

I’ve been running several webservers behind custom domains for a while now (plateyplatey.com, textadventurer.tk, and this site) and it never ceases to amaze me how cheeky bots are getting.

For example, certbot recently started complaining that textadventurer.tk’s TLS certificate is about to expire. That shouldn’t happen because there’s a nightly cronjob for certbot renew.

On SSHing into the server I found an immediate problem: the disk was full. Why? Because some bot, listed as from contabotserver.net decided to spam the server with >10 million requests one afternoon and fill the HTTP logs. Great. Looks like I’m finally going to implement some log compression+rotation.

Then there’s the almost hourly attempts to find a PHPMyAdmin panel on my sites. That one always surprised me: surely only a small percentage of PHP sites are misconfigured that badly? Lets look at the stats:

Percentage of websites using PHP

Even if 1 % of them are misconfigured, we’re doomed.

Jobson: Now in 2D

Nov 25, 2017

I recently made screencasts that explain Jobson in more detail. The first explains what Jobson is and how to install it. Overall, Jobson seems well-recieved. The first video seems to be leveling off at around 2700 views and Jobson’s github repo has seen a spike in attention.

Will other teams start adopting it or not? Only time will tell.