What job postings actually ask for

Public job postings published by employers on their own career sites, retrieved through the official Greenhouse, Lever and Ashby job-board APIs — documented, unauthenticated endpoints, not scraping. The corpus currently holds 12,425 postings across 37 role families with enough coverage to report on.

Each posting's full text is read once and the skills it names are extracted. A term is counted a single time per posting no matter how often it repeats, so one keyword-stuffed listing cannot inflate a figure. The percentage is that count divided by the number of postings in the role family, and every page shows both numbers.

Postings are re-checked every six hours, and a posting drops out of the window once it hasn't been seen for 90 days. Every figure therefore describes roles being hired for now, not a historical archive.

A role is published only once at least 50 postings back it. Below that a percentage swings wildly on a handful of listings, so nothing is shown at all.