Project archive

This suite caught Brightway's LCA calculator, bw2calc 3.0.0, running its iterative solver about five times slower when the optional PyPardiso solver is missing. I reported it, and the maintainer's fix shipped in 3.1.0. It tracks speed across Brightway releases and checks each score against an independent calculation, on made-up databases shaped like ecoinvent.

BSD-3-Clause

Publishers sometimes revise a data file without saying so, and results built on it change. sourceledger, a Python library, stamps each row of a dataset with the download it came from (URL, time and SHA-256) and flags a source that has changed since. It writes Frictionless Data Packages and is on PyPI with a Zenodo DOI.

v0.5.1DOIMIT

A backup container once crash-looped 668 times over 19 hours while every monitor read green. So I redesigned CML's shared monitoring: now a scheduled job that stops checking in raises an alarm. Logs, traces and metrics come in through OpenTelemetry and link up in Grafana, and R9lab sends to it today.

Used by R9lab

I start new projects from these Copier templates for Python, TypeScript, Rust, Go and Docker. Each gets tests, CI and releases that need no stored keys, and copier update pulls in later template fixes.

DOIMIT

CodeMeta, a standard for describing research software, disagrees with itself. This tool compares its list of fields, its examples and its 46 mappings to other formats. In the development version, every one of the 46 mappings still listed a field the standard had dropped, which I raised with the maintainers.

DOIApache-2.0

Generate CITATION.cff, codemeta.json and .zenodo.json from a citation file or package metadata in the browser playground. The CLI and pre-commit hook keep them in sync using CodeMeta's crosswalks, as exported by codemeta-drift.

v0.5.0DOIApache-2.0

In The Hague, offices have 11% of the floor area but cause 79% of the greenhouse-gas emissions from cooling. I rebuilt the model from my MSc Industrial Ecology thesis (Leiden / TU Delft) as a Snakemake pipeline: an hourly heat balance for 59,381 buildings from the Dutch building register (BAG), followed by LCA.

GPL-3.0-or-later

A drawing and guessing game you play live with friends in the browser, built with Vue 3 and FastAPI. In a load test, one server container with one CPU kept about 200 rooms of 6 players going, with 95% of messages arriving within 250 ms.

My answer to the roadmap.sh file integrity checker exercise, written three times: in bash, Python and Rust. All three share one signed fingerprint format, and a test checks that they agree on random files. It has a written threat model and refuses an older signed record put back in place.

A period tracker that keeps every entry on your device and sends nothing anywhere. On the past records of 581 people in an open dataset, its next-period prediction is off by 2.0 days on average after six cycles, against 2.6 days for a fixed 28-day cycle.

Remembers where you parked your bike, the way a station bike park labels it (lane, rack level, rack number), with an optional photo and GPS position. It installs from the browser, works offline, keeps everything on your device, and speaks seven languages.

An unofficial table companion for the Scattergories party game. It draws each letter from the language's own alphabet, weighted by how often that language uses it, in nine languages. It also picks the categories and runs the timer.

A daily page for The Hague: the day's picture, a few sourced facts, the weather, a quiz and a list of daily web games, under a sky that follows the sun's position. Checkmarks and streaks stay in your browser, and the server keeps nothing beyond Cloudflare's request logs.

A FIRE and net-worth planner for Dutch households. Its tax engine covers Box 3, mortgage interest, transfer tax and fiscal partners, and every tax figure is dated and cites its source. The plan stays in a file on your machine, and a browser build runs the same Python engine client-side.

a proposed resource hub for the AI for industrial ecology working group, with 75 literature entries and in-browser demos.

a demo gallery of CML's research projects, one Markdown file per project, filtered in the browser.

a marimo course on environmentally extended input-output analysis that runs in the browser, with self-checks that rerun as you move the sliders.