# Nostr Mail Settings

This document defines the protocol for storing and synchronizing user settings across devices in Nostr Mail using NIP-78 application-specific data.

# Overview

User settings are stored as replaceable parameterized events (kind 30078). This enables seamless synchronization across multiple devices while maintaining privacy through encryption.

# Event Kind

# Kind 30078: Application-Specific Data

Settings use NIP-78 replaceable parameterized events with the d tag for namespacing.

# Public Settings

Public settings are stored unencrypted and can be read by anyone.

{
  "kind": 30078,
  "pubkey": "<user_pubkey>",
  "tags": [["d", "nostr-mail/settings"]],
  "content": "{\"dm_copy\": true}"
}

# Fields

Field	Type	Description
`dm_copy`	boolean	Request bridges to send a DM copy of incoming emails

# Private Settings

Private settings MUST be encrypted to self using NIP-44.

{
  "kind": 30078,
  "pubkey": "<user_pubkey>",
  "tags": [["d", "nostr-mail/settings/private"]],
  "content": "<nip44_encrypted_json>"
}

# Decrypted Content

After decryption, the content contains:

Field	Type	Description
`default_address`	string	Default "From" address (e.g. `npub1...@bridge.com`)
`signature`	string	Email signature appended to outgoing emails
`bridges`	string[]	List of preferred bridge domains

# Example (Decrypted)

{
  "default_address": "npub1abc...@nostr.mail",
  "signature": "Sent via Nostr Mail",
  "bridges": ["nostr.mail", "bridge.example.com"]
}

# Example (Encrypted Event)

{
  "kind": 30078,
  "tags": [["d", "nostr-mail/settings/private"]],
  "content": "<nip44_encrypted_blob>"
}