Andrew Kvalheim

Path decomposition diagram

iD and OSMCha follow the convention of distinguishing between changeset source and imagery_used, but JOSM by default overloads source to serve both purposes.

DMARC offers a mechanism for the public to report observations about mail claiming to be from your domain.

I was thinking recently about the various decisions we make around what technologies to let into our lives, and how my own decisions have changed over time.

pngquant is a convenient command-line utility for lossily reducing the data size of PNG images by selectively removing colors.

I check the weather in Celsius, weigh espresso beans in grams, measure water in milliliters, estimate distances in meters, use a 24-hour clock, and write dates in big-endian order.

For years I’ve been curious about type design but lacked sufficient reason to pursue it; creating a typeface is an ambitious and highly time-consuming project.

If GNOME Shell crashes it automatically disables all extensions in case they were responsible.

Two linguistic errors arising from technological ignorance have become commonplace: the mispronunciation of GIF, despite the term’s intended homage to a homonymous peanut butter the indiscriminate misreference to any moving picture as a GIF despite its li…

My camera writes photos in the High Efficiency Image File Format (HEIF) but darktable doesn’t yet support reading them.

The number keys on my laptop have been gradually failing, so a couple of weeks ago I borrowed a trick from my split keyboard and put a virtual number pad under the right hand’s home position, activated by the right Alt key: This is accomplished using a ke…

Before giving a spare Iris to a friend who’s never used a split keyboard, I wanted to reset the layout from my personalized one to something less formidable.

I’ve occasionally wanted to look back at past versions of OpenStreetMap, but the project’s architecture makes that resource intensive so there aren’t any public services offering the ability.

I’ve been interested in trying regular short breaks from the screen, but in practice scheduling them can be tricky.

As pretext for socializing during the COVID-19 lockdowns we’ve spent several evenings playing Minecraft with friends remotely.

After years of talking about upgrading our espresso equipment, we finally bought a used E61 single-boiler machine.

D'ni numerals on the web

The buildings added to OpenStreetMap as part of the Edmonds import contained many redundant points, i.e. points in a line that contribute nothing to the shape of the building: To clean these up I created a small script for the JOSM Scripting Plugin to det…

In his talk The math and magic of origami Robert Lang introduces TreeMaker, a computational origami tool that calculates paper crease patterns from stick figure–like tree diagrams.

I've created a rudimentary Git diff driver for Anki decks.

In a typical design of a nuclear reactor, control rods are suspended above the core by electromagnets such that, in the event of a power failure, they automatically fall under gravity into a safe configuration.

In contrast to popular opinion about work interruptions, I've found that being interrupted with a simple prompt to explain what I'm doing is actually often helpful.

Hairball, artist's rendition

After various experiments in rigging up more ergonomic mice, I’ve accepted that the primary contributor to my wrist pain is the traditional keyboard which traps the wrists at a strained position.

The feed template in middleman-blog uses file modification times to determine when articles were updated.

I recently saw the Circle of Friends symbol casually referred to as “the spinning logo”.

GSLUG has a server that's informally co-administered by several people.

I recently had occasion to display a terminal session on a web page.

I've created middleman-pry to replace Middleman's built-in console with a Pry console: andrew.kvalhe.im$ middleman console ruby:Middleman::Application$ Pry lets you explore the context of your code as you would a filesystem.

The manual for the Buon Caffé model 330 claims that the machine “provides outstanding steaming power”, but experience has shown it to be lacking.

Dropbox LAN sync is now included in Debian and Ubuntu's list of known services, so firewall configuration is as simple as: sudo ufw allow db-lsp

Honey bees

GitHub provides code frequency plots that show the number of lines added and removed within a repository over time: Here's a quick and dirty method to visualize this information from any local repository in more chronological detail, using the calendarHeat

A user survey.

Inspired by Ryan Alexander's Mycelium, I took a moment today to try to recreate something similar.

Visualization of time-dependent ordinal rankings

Quantal Quetzal's colors

This is my computer.

The search for a more ergonomic wrist position has led me to experiment with upside-down mice.

After a couple years of use my bike horn stopped making any noise when air flowed through.

For holiday gifts we decorated several travel mugs with illustrations of proteins such as α-hemolysin: The task of placing this on the surface of a mug poses some tricky questions.

Dot stickers make an excellent tool for customizing the Apple aluminum keyboard.

I drew a picture of ATP: That’s what it stands for, right?

Rockbox has the ability to generate Audioscrobbler logs for later submission to Last.fm.

I’m currently experimenting with a low-effort technique for mimicking the benefits of a hybrid solid state/hard disk drive.

Visual feedback for your moodbar scanner: This is a pseudo-graphical application of AWK.

The right birthday card for a Minecraft alpha gift code.

The backlight of this Canon PowerShot SD400 doesn’t work anymore, but the rest of the LCD is fine: I can order a new backlight for about $20 via eBay.

When Molecular Devices's MetaMorph software exports colorized images in the TIFF file format, it creates 8-bit palette color TIFFs but neglects to embed the color palette in format that is readable by conventional image viewers.

In the same vein as the “distraction-free writing” features of WriteRoom and PyRoom, a custom color scheme for gedit can be leveraged to hide all text except for the current line.