Don't give up on privacy.

// Package.swift: .package(url: "https://github.com/julianbonomini/trueseal-sync-swift", from: "0.6.0")
import TruesealSync

let ts = try await TrueSeal.open(
    relay: "trueseal://9f2c…e41a@relay.example.com",
    storage: try FileManager.default.url(
        for: .applicationSupportDirectory, in: .userDomainMask,
        appropriateFor: nil, create: true)
)

ts.onMessage { message in
    try await store.save(message.id, message.body)
}
ts.onEvent { event in
    if case .joinRequest(let request) = event {
        try? ts.accept(requestId: request.id)
    }
}

let token = try ts.startPairing() // show it as a QR code
try ts.join(token: scannedToken) // on the other device
try ts.send(location)

// build.gradle.kts: implementation("dev.trueseal:trueseal-sync:0.6.0")
import dev.trueseal.sync.Storage
import dev.trueseal.sync.TrueSeal
import dev.trueseal.sync.TrueSealEvent
import kotlinx.coroutines.launch

val ts = TrueSeal.open(
    relay = "trueseal://9f2c…e41a@relay.example.com",
    storage = Storage.android(context),
)

ts.onMessage { message ->
    repository.save(message.id, message.body)
}
ts.onEvent { event ->
    if (event is TrueSealEvent.JoinRequestReceived) {
        scope.launch { ts.accept(event.request.id) }
    }
}

val token = ts.startPairing() // show it as a QR code
ts.join(scannedToken) // on the other device
ts.send(location)

// npm install @trueseal/sync
import { TrueSeal } from '@trueseal/sync'

const ts = await TrueSeal.open(
  'trueseal://9f2c…e41a@relay.example.com',
  { storageDir: './trueseal-state' },
)

ts.onMessage(async (message) => {
  await db.put(message.id, message.body)
})
ts.onEvent((event) => {
  if (event.type === 'joinRequest') {
    ts.accept(event.request.id)
  }
})

const token = ts.startPairing() // show it as a QR code
ts.join(scannedToken) // on the other device
await ts.send(location)