Nostr Book of NIPs

NIP-78

Arbitrary custom app data

draft optional relay

The goal of this NIP is to enable remoteStorage-like capabilities for custom applications that do not care about interoperability.

Even though interoperability is great, some apps do not want or do not need interoperability, and it wouldn’t make sense for them. Yet Nostr can still serve as a generalized data storage for these apps in a “bring your own database” way, for example: a user would open an app and somehow input their preferred relay for storage, which would then enable these apps to store application-specific data there.

These kinds are not meant to be used as a generic interchange format for data that should be public or exchanged between different applications. Applications that need such interoperability should use dedicated kinds instead.

Nostr event

This NIP specifies the use of event kinds 30078 (an addressable event) with a d tag containing some reference to the app name and context – or any other arbitrary string. content and other tags can be anything or in any format.

It also defines the kind 78 (a normal event) for when the app needs to store and query multiple events of the same type. Apps should use some unique tag (even a d tag) for grouping these events together.

AUTH

Because this data is private to the user, relays SHOULD require clients to perform the NIP-42 AUTH flow before accepting or serving kind 78 and kind 30078 events, and SHOULD only serve these events to the authenticated owner, i.e. the client must authenticate with the same pubkey as the event author.

Some use cases