Plain Russian or English schedules → cron, RRULE and systemd.
"every weekday at 9:30" → 30 9 * * 1-5

▶ Playground

Offline Russian production calendar: workdays, holidays, hour norms.
Publishes itself to npm when a new year is approved.

Operator and region of a Russian phone number, offline.
From the official numbering registry, refreshed weekly.

▶ Playground

Bank of Russia BIK directory offline
and checks for INN, SNILS, OGRN and bank accounts.

▶ Playground