@flexpay/core

Headless FlexPay SDK logic for Solana payments.

What It Does

• Reads payable SPL token balances for a wallet
• Fetches Jupiter quotes for exact-out USDC settlement
• Builds unsigned swap transactions
• Submits signed transactions and waits for confirmation
• Exposes a FlexPayClient class for full payment orchestration

Main Exports

• FlexPayClient
• fetchQuote
• buildSwapTransaction
• submitTransaction
• getTokenBalances
• getJupiterTokenList
• mergeTokenData

Example

import { FlexPayClient } from "@flexpay/core";

const client = new FlexPayClient({
  merchantWallet: "YOUR_MERCHANT_WALLET_OR_USDC_ATA",
  rpcEndpoint: "https://api.devnet.solana.com"
});

const result = await client.executePayment({
  inputMint: "So11111111111111111111111111111111111111112",
  amount: 29.99,
  userPubkey: wallet.publicKey.toBase58(),
  signTransaction: wallet.signTransaction
});

Notes

• This MVP follows the exact-out flow from the project brief.
• Jupiter URLs are configurable so you can migrate endpoints later without changing the public API.