Software

Open-source software tools I have built or maintain:

dragon, a drag and drop source/target for X11. dragon file.jpg creates a window with a single entry you can drag into a file manager or web browser.
retail, a POSIX-compatible tail with regular expression support. retail -r REGEX will output the part of the file starting at the last match of REGEX, and retail -f -r REGEX1 -u REGEX2 will output the part of the file starting at the last occurrence of REGEX1, and keep outputting until REGEX2 matches.
jqjs, a JavaScript implementation of the jq query language, implementing the core language features in pure JavaScript that runs in the browser.
A tool to generate accurate Windows 3.x dither patterns in-browser.
Kernan and Minigrace, two implementations of the Grace language.
Tiled Grace, a block-based editor for Grace.
A regular expression analyser that runs in the browser, showing both NFA and DFA for a regex and simulating them against strings.
domejs, a JavaScript DOM library using proxies to make common operations shorter while still resembling the standard DOM API.
Exploratory tool for the 2020 New Zealand general election results, down to the level of individual polling places.