Holiday data used by Holitide: source and license

Holitide's holiday dates (src/data/holidays.json, bundled into the app) are generated by scripts/gen-holiday-data.ts from the date-holidays package by commenthol and contributors, version pinned in package.json (3.37.0 at first release).

• Project: github.com/commenthol/date-holidays
• Code license: ISC.
• Data license: Creative Commons Attribution-ShareAlike 3.0 (CC BY-SA 3.0), because most of the data comes from Wikipedia articles. The per-country attributions are in the project's data/countries/*.yaml files.

What we did with it

We evaluated the project's holiday rules for the years 2025 to 2036, kept public, bank and optional holidays (dropping school holidays and observances), kept countries and their first-level regions (states, provinces, nations, cantons), and stored the resulting dates and names in a compact table. That table is an adaptation of the date-holidays data and is therefore licensed under CC BY-SA 3.0: anyone may reuse src/data/holidays.json under that license, with attribution to the date-holidays project and contributors. The rest of Holitide (its code, design and copy) is proprietary to Great Work LLC and is not covered by that license.

Where we show the attribution

• In the app, at the bottom of the main page.
• On the listing (long description, "Your data").
• On the docs page (built from DOCS.md) and here.