• The hidden centralization in every dApp
• A different path: Nostr as the delivery network
• What this means for you as a developer
• Real code, real simple
• Free tier, Pro tier, and beyond
• Try it today

You’ve done the hard work. Smart contracts – checked. Transactions – flowing.
Frontend – talking to the blockchain.
Everything is decentralized, trustless, transparent.

Then you need a price. A simple Bitcoin price.

And suddenly you’re back in Web2: API keys, rate limits, CORS errors, and a single provider you have to trust.

Sound familiar?

Discover how we bring verifiable, key‑less price data to Bitcoin developers.

§The hidden centralization in every dApp

Decentralized applications have a dirty secret: the price data that powers them is almost always pulled from a centralized API.

• CoinGecko – great service, but requires an API key and trust.

• CoinMarketCap – similar model, central point of failure.

• Direct exchange APIs – even worse: expose your frontend to CORS and key theft.

You embed an API key in your frontend code (because you have no backend). That key gets scraped. Your quota is burned by someone else. Or the API changes its terms, and your dApp breaks overnight.

On‑chain oracles exist, but they’re clunky for frontend use: gas costs, transaction delays, and smart contract complexity. For a simple price display, it’s overkill.

§A different path: Nostr as the delivery network

We asked: what if price data was distributed like Bitcoin transactions – but designed for developers?

Then we shipped PriceStr.

PriceStr is a signed Bitcoin price feed built natively for the Nostr protocol. Here’s how it works:

1. Aggregate – We pull prices from Binance, Kraken, and Coinbase every cycle and compute the median (eliminating outliers and manipulation).

2. Sign – Each price event is cryptographically signed by PriceStr’s Nostr keypair. The signature is deterministic – any Nostr library can verify it in one function call.

3. Broadcast – The signed event is published to the Nostr relay network.

4. Consume – Your dApp queries any relay. It doesn’t matter which one. The signature is the truth, not the relay.

No API key. No database. No central point of control.

§What this means for you as a developer

You can now build truly static frontends – hosted on IPFS, served from a CDN – that fetch and verify live Bitcoin prices without a backend, without an API key, and without trusting us.

§Real code, real simple

Using nostr-tools in your browser:

import { relayInit, verifyEvent } from 'nostr-tools';

const relay = relayInit('wss://relay.pricestr.xyz');
await relay.connect();

const sub = relay.sub([
  { kinds: [31890], authors: [PRICESTR_PUBKEY] }
]);

sub.on('event', event => {
  if (verifyEvent(event)) {
    const price = JSON.parse(event.content).aggregate;
    document.getElementById('btc-price').innerText = `$${price}`;
  } else {
    console.warn('Invalid signature – discarding');
  }
});

That’s it. No API calls. No headers. No keys. Just a verified price appearing on your page.

§Free tier, Pro tier, and beyond

We believe price data should be open and verifiable for everyone.

• Free – BTC/USD every 60 seconds, broadcast to public relays. Perfect for hobby projects, testing, and static sites.

• Pro ($15/month) – 10‑second updates, dedicated PriceStr relay + backups, forex pairs, webhooks.

• Enterprise – Private relay, custom pairs, SLA, and dedicated support.

All payments are Bitcoin‑only via Lightning – because a Bitcoin price feed should be paid for with Bitcoin.

§Try it today

Visit pricestr.xyz to get the public key, see the live feed, and start integrating.

Your dApp deserves better than an API key on a sticky note.

PriceStr is developed by HexQuarter. Built on Nostr. Powered by Bitcoin.