Building an npm Package with Lightning Network Micropayments (L402)

Source: Dev.to

Overview

I just published my first npm package that uses the Lightning Network for micropayments: lightning-bitcoin-query.

Traditional API services charge $29‑199/month for unlimited requests, but most developers only need a few API calls per day. Why pay for unused quota?

Pay‑per‑query with Lightning Network micropayments

• 10 sats (~$0.01) per mempool check
• 20 sats (~$0.02) per transaction lookup
• No API keys
• No rate limits
• No subscriptions

Installation

npm install lightning-bitcoin-query

Usage

const BitcoinQuery = require('lightning-bitcoin-query');

const bitcoin = new BitcoinQuery({
  nwcUri: process.env.NWC_URI // From your Lightning wallet
});

// Makes HTTP request → Gets 402 → Pays invoice → Returns data
const mempool = await bitcoin.getMempool();

How It Works (L402 Protocol)

1. Try API request
2. Receive 402 Payment Required with a Lightning invoice
3. Pay invoice automatically via NWC wallet
4. Cache payment hash for 5 minutes
5. Retry request with payment proof
6. Return blockchain data

• Instant: Payments confirm in

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What other APIs would benefit from micropayments? Let me know in the comments!