Small tools I’ve built and put online.
If you want one harness that works across several coding agents, this shows what each of today’s agents supports out of the box: instruction files, skills, hooks, MCP servers, policy and packaging. Every cell is sourced, and each review is logged.
A study guide for the Claude Certified Architect (Foundations) exam. It has 14 prep pages, a drill with a 134-question bank and 36 recall cards, and a 16-chapter companion book, compiled into one HTML file you can read offline. No runtime dependencies.
A diff tool built on the Monaco diff editor. Side-by-side or inline view, drag-and-drop files, and live stats on what was added, removed and changed.
Paste some JSON, browse it as an expandable tree, and query it with JSONata. Results update as you type, and there’s autocomplete.
Berlin’s official street-cleaning classes, the Reinigungsklassen, on an interactive MapLibre GL map of the whole city. In German and English, with address search and a filter for each class.
Generates wall patterns you can paint with masking tape: straight lines only and no more than three colors. Exports to PNG.
The 40 classic Rush Hour-style puzzles. Slide the other vehicles out of the way to get the red car out. Has a move counter and a timer, and installs as an app for offline play.
Shows one short poem at a time, picked at random from a small collection.