Custom software for the way you actually work.

A dashboard fed pre-computed totals can only answer the questions whoever prepared the data had anticipated. The first different question needs a change, a release and a week.

The browser receives the municipal detail — 7,896 rows — and aggregates on the fly. Changing level, indicator or filter is not a request to a server: it is a loop over an array.

The map weighs 99 KB because it is TopoJSON: quantised coordinates, points stored as deltas, and borders shared between neighbouring regions rather than duplicated. The same drawing as GeoJSON weighs 2,700.

Fifty-one checks that reconcile the totals by every route and test them against facts that do not come from the data. On the first run Italy’s population came out at 118 million: the ISTAT file carries a total row per municipality, and summing it with the detail counts everything twice.

A contrast ratio is a single number, and on its own it decides nothing: the same pair of colours passes at 24 px and fails at 16. The tools you find show the number with two fixed ticks beside it, and the real question goes unanswered — from what size up is this colour fine?

The threshold moves with size and weight, because that is how the standard is written. Transparency is composited before it is measured: rgba(0,0,0,.5) on white is #808080 and scores 3.95:1, not 21:1 — a tool that ignores alpha returns a number that exists on no screen.

And when it fails, it says which colour to use instead. The fix moves in lightness only, inside OKLCh, so the hue stays put and a corrected red stays red rather than turning pink. Sometimes, though, the right answer is that the background is wrong: on a mid grey no text colour whatsoever reaches 7:1, and saying so is worth more than offering a colour that does not solve it.

The real work is not one pair but a whole theme, where the pairs are n×n: paste the custom properties of a stylesheet and they all come out at once.

A hundred and eighty-one checks, eight of them against numbers published by other people that I did not compute anywhere myself. The expectations are recomputed by a second implementation written in Python from the specification, not by the engine they are meant to test. And the page’s own theme passes its own tool against AAA, not AA: the check re-reads the stylesheet from disk, so a colour changed without looking at the contrast makes it fail.

Measuring the rendered page, rather than the declared colours alone, it found a defect of its own: on the matrix diagonal a grey dash at 12 px sat at 4.05:1. It was decoration disguised as text, and it is now a hatch.