@peltier/core

Any ERC-20 on any chain → USDC at your destination. This is the React-free protocol core every other Peltier package builds on: payment flow primitives, a fetch-based API client, EIP-712 signing, stealth-address derivation, webhook verification, and x402 wire types.

No React, no DOM, no node: imports — runs in Node 18+, Bun, Deno, edge runtimes, browsers, and React Native.

npm install @peltier/core viem

Which package do I want?

| You are building | Install | |---|---| | A backend (402 gate, webhooks, subscriptions) | @peltier/node — re-exports all of core | | A React web app | @peltier/react — widgets + hooks | | A React Native app | @peltier/react-native — RN widgets + hooks | | Anything else (CLI, agent, worker, custom UI) | this package |

Quickstart

import { createPeltierClient } from '@peltier/core'

const peltier = createPeltierClient({
  apiUrl: 'https://api.peltier.dev',
  publishableKey: 'pk_live_…', // or secretKey: 'sk_live_…' on a server
})

// Register a deposit session, then watch it settle
const session = await peltier.registerSession({ /* … */ })
peltier.watchSession(session.id, (update) => {
  console.log(update.status)
})

Every session / merchant / subscription method is bound to the one config object. The free functions (registerSession, watchSession, getQuote, createPaymentSession, …) remain exported as the low-level escape hatch — same behavior, explicit apiUrl argument.

What's inside

• Flow primitives — deposit, request/receive (createRequestSession, buildOpenTokenIntent), send, and stealth flows; createBurnerWallet for ephemeral depositor keys.
• API client — createPeltierClient plus free functions: registerSession, commitIntent, getQuote, fetchBalances, createPaymentSession, watchSession (SSE with automatic reconnect + polling fallback), and more.
• EIP-712 signing — signIntent, signRefund, signStandingRefund, typed-data builders (intentTypedData, refundTypedData) that byte-match the on-chain PeltierDelegate contracts.
• Stealth addresses — meta-address derivation, announcements, and withdrawal helpers for EVM and Solana (StealthMetaAddress, StealthKeys).
• Webhooks — verifyWebhookSignature(payload, signature, secret) (async) and verifyWebhookSignatureDetailed returning { ok, reason }.
• x402 — parse402 and the X402Body / X402Accepts wire types for agent-side handling of HTTP 402 payment challenges.
• Subscriptions — subscriptionTypedData, subscriptionId, and the typed REST surface for recurring on-chain charges.
• Test mode — Stripe-style key parity: pk_test_ / sk_test_ keys route to testnets automatically (keyMode, chainsForMode, TESTNET_CHAINS).

Error handling

Every API call throws a typed PeltierApiError instead of a bare Error:

import { isPeltierApiError } from '@peltier/core'

try {
  await peltier.getSession(id)
} catch (err) {
  if (isPeltierApiError(err)) {
    // err.status, err.endpoint, err.kind: 'http' | 'network' | 'timeout' | 'parse'
  }
}

Every call also accepts trailing opts?: { timeoutMs?, signal?, fetch? } — default timeout 30 s.

Supported chains

Mainnet: Ethereum, Arbitrum, Base, Optimism, Polygon, Monad, HyperEVM (destination-only), and Solana (deposit source + settlement destination). Each EVM chain has a testnet counterpart reached automatically with pk_test_ / sk_test_ keys. Full matrix: peltier.dev/docs/supported-chains.

Docs

Full documentation lives at peltier.dev/docs.

License

MIT