NIP: Decentralized appointment scheduling (kind 31927)

[geralt-debugs]

Summary

Adds a new NIP defining a privacy-preserving, decentralized appointment scheduling protocol built on Nostr, a
drop-in alternative to Calendly/Cal.com with no central intermediary.

What this proposes

• Kind 31927 - Scheduling Page: NIP-44 encrypted availability config; only readable by those with the share URL's
  view key.
• Kind 32680 - Key Index: Self-encrypted host-side record for recovering the view key on new devices.
• Kind 31926 - Public Busy List: Free/busy publishing without leaking appointment details (already defined in
  NIP-52E).
• Kind 1057/57 - Booking Request: NIP-59 gift-wrapped request from booker to host, carrying a pre-generated d tag
  and view key so the booker can add the event to their calendar immediately.
• Kind 1058/58 - Booking Response: NIP-59 gift-wrapped approval or decline from host to booker.
• Kind 32678/1052 - Private Calendar Event: Confirmed appointment encrypted with the booker's key (per NIP-52E);
  neither relay nor third party learns the appointment details.

Privacy model

• Scheduling page body is encrypted; only the d tag is public.
• Booking messages are gift-wrapped under ephemeral keys.
• The confirmed appointment is encrypted with a key the booker generates; the host never has exclusive control
  over it.
• Busy list reveals when but not what or with whom.

Dependencies

Depends on NIP-52E (Private Calendar Events) for kinds 32678 and 1052. It is possible to create public calendar events as well

[samuelmanzanera]

This is interesting, is it based on an existing implementation?

[geralt-debugs]

Hey @samuelmanzanera yes we have implemented it at https://calendar.formstr.app/ or Calendar android app along with the companion nips(52 and its proposed extensions)

github: https://github.com/formstr-hq/nostr-calendar

[samuelmanzanera]

Hey @samuelmanzanera yes we have implemented it at https://calendar.formstr.app/ or Calendar android app along with the companion nips(52 and its proposed extensions)

github: https://github.com/formstr-hq/nostr-calendar

Thanks . I will definitely check it out