kkachi

Client SDK for kkachi — a blind Web Push server for Nostr gift-wrap (kind:1059) notifications.

• Derive a per-epoch inbox key (HKDF → secp256k1) that never leaves the device.
• Register/unregister with the push server via NIP-98 (with timeout + retry).
• Shared wire contract (protocol.ts) so the server and SDK never drift.

Ships TypeScript source (bundler/Bun consumers). Receiving/decrypting is the client's responsibility, not this SDK's.

Install

bun add kkachi
# npm i kkachi

Usage

import { createInboxSigner, subscribe, unsubscribe } from 'kkachi/register'
import { deriveInboxPub } from 'kkachi/inbox-key'
import type { PushMaterial } from 'kkachi/protocol'

const signer = await createInboxSigner(walletSeed, '2026-09') // rotate monthly
const inboxPub = signer.inboxPub // hand to senders (gift-wrap `#p`)

const push = subscription.toJSON() as PushMaterial
await subscribe('https://push.example', signer, push, ['wss://inbox.example'])
await unsubscribe('https://push.example', signer)

Subpaths: kkachi/protocol, /inbox-key, /register.

License

MIT