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#1	# Crypto Payments
#2
#3	Accept cryptocurrency payments in your applications.
#4
#5	## Simple SOL Payment
#6
#7	```tsx
#8	import { useSolana, useAccounts } from "@phantom/react-sdk";
#9	import { Connection, PublicKey, SystemProgram, VersionedTransaction, TransactionMessage } from "@solana/web3.js";
#10
#11	function PayButton({ recipient, amountSol }: { recipient: string; amountSol: number }) {
#12	const { solana } = useSolana();
#13	const { isConnected } = useAccounts();
#14	const [status, setStatus] = useState<"idle" \| "paying" \| "success" \| "error">("idle");
#15
#16	async function handlePay() {
#17	setStatus("paying");
#18	try {
#19	const connection = new Connection("https://api.mainnet-beta.solana.com");
#20	const { blockhash } = await connection.getLatestBlockhash();
#21	const wallet = await solana.getPublicKey();
#22
#23	const message = new TransactionMessage({
#24	payerKey: new PublicKey(wallet),
#25	recentBlockhash: blockhash,
#26	instructions: [
#27	SystemProgram.transfer({
#28	fromPubkey: new PublicKey(wallet),
#29	toPubkey: new PublicKey(recipient),
#30	lamports: Math.floor(amountSol * 1e9),
#31	}),
#32	],
#33	}).compileToV0Message();
#34
#35	const tx = new VersionedTransaction(message);
#36	await solana.signAndSendTransaction(tx);
#37	setStatus("success");
#38	} catch {
#39	setStatus("error");
#40	}
#41	}
#42
#43	return (
#44	<button onClick={handlePay} disabled={!isConnected \|\| status === "paying"}>
#45	{status === "paying" ? "Processing..." : `Pay ${amountSol} SOL`}
#46	</button>
#47	);
#48	}
#49	```
#50
#51	## SPL Token Payment (USDC)
#52
#53	```tsx
#54	import { getAssociatedTokenAddress, createTransferInstruction, createAssociatedTokenAccountInstruction, getAccount } from "@solana/spl-token";
#55
#56	const USDC_MINT = "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v";
#57
#58	async function payWithUSDC(solana: any, recipient: string, amount: number) {
#59	const connection = new Connection("https://api.mainnet-beta.solana.com");
#60	const { blockhash } = await connection.getLatestBlockhash();
#61	const wallet = await solana.getPublicKey();
#62
#63	const mint = new PublicKey(USDC_MINT);
#64	const from = new PublicKey(wallet);
#65	const to = new PublicKey(recipient);
#66
#67	const fromAta = await getAssociatedTokenAddress(mint, from);
#68	const toAta = await getAssociatedTokenAddress(mint, to);
#69
#70	const instructions = [];
#71
#72	// Create recipient's token account if needed
#73	try {
#74	await getAccount(connection, toAta);
#75	} catch {
#76	instructions.push(createAssociatedTokenAccountInstruction(from, toAta, to, mint));
#77	}
#78
#79	// Transfer (USDC has 6 decimals)
#80	instructions.push(createTransferInstruction(fromAta, toAta, from, amount * 1e6));
#81
#82	const message = new TransactionMessage({
#83	payerKey: from,
#84	recentBlockhash: blockhash,
#85	instructions,
#86	}).compileToV0Message();
#87
#88	return await solana.signAndSendTransaction(new VersionedTransaction(message));
#89	}
#90	```
#91
#92	## Checkout with Backend Verification
#93
#94	### Client
#95
#96	```tsx
#97	async function checkout(orderId: string, solana: any) {
#98	// 1. Create payment on backend
#99	const { paymentId, transaction } = await fetch("/api/payments/create", {
#100	method: "POST",
#101	body: JSON.stringify({ orderId }),
#102	}).then(r => r.json());
#103
#104	// 2. Sign and send
#105	const { hash } = await solana.signAndSendTransaction(
#106	Buffer.from(transaction, "base64")
#107	);
#108
#109	// 3. Confirm with backend
#110	const { success } = await fetch("/api/payments/confirm", {
#111	method: "POST",
#112	body: JSON.stringify({ paymentId, txHash: hash }),
#113	}).then(r => r.json());
#114
#115	return success;
#116	}
#117	```
#118
#119	### Server
#120
#121	```ts
#122	// /api/payments/create.ts
#123	export async function POST(req: Request) {
#124	const { orderId } = await req.json();
#125
#126	// Get order, calculate amount
#127	const order = await db.orders.findUnique({ where: { id: orderId } });
#128	const solAmount = order.total / await getSolPrice();
#129
#130	// Create payment record
#131	const payment = await db.payments.create({
#132	data: { orderId, solAmount, status: "pending" }
#133	});
#134
#135	// Build transaction (partial - user will sign)
#136	// Return serialized transaction
#137
#138	return Response.json({ paymentId: payment.id, transaction: "..." });
#139	}
#140
#141	// /api/payments/confirm.ts
#142	export async function POST(req: Request) {
#143	const { paymentId, txHash } = await req.json();
#144
#145	// Verify transaction on-chain
#146	const connection = new Connection("https://api.mainnet-beta.solana.com");
#147	const tx = await connection.getTransaction(txHash, { commitment: "confirmed" });
#148
#149	if (!tx) return Response.json({ success: false });
#150
#151	// Verify amount and recipient match
#152	// Update payment status
#153	// Fulfill order
#154
#155	return Response.json({ success: true });
#156	}
#157	```
#158
#159	## Price Display with Live Rates
#160
#161	```tsx
#162	function PriceDisplay({ usdAmount }: { usdAmount: number }) {
#163	const [solPrice, setSolPrice] = useState(0);
#164
#165	useEffect(() => {
#166	async function fetchPrice() {
#167	const res = await fetch("https://api.coingecko.com/api/v3/simple/price?ids=solana&vs_currencies=usd");
#168	const data = await res.json();
#169	setSolPrice(data.solana.usd);
#170	}
#171	fetchPrice();
#172	const interval = setInterval(fetchPrice, 60000);
#173	return () => clearInterval(interval);
#174	}, []);
#175
#176	const solAmount = solPrice ? (usdAmount / solPrice).toFixed(4) : "...";
#177
#178	return (
#179	<div>
#180	<p>${usdAmount} USD</p>
#181	<p>≈ {solAmount} SOL</p>
#182	</div>
#183	);
#184	}
#185	```
#186
#187	## Best Practices
#188
#189	1. Always verify on-chain - Don't trust client-side alone
#190	2. Use unique payment IDs - Track each payment
#191	3. Handle price volatility - Lock prices or use stablecoins
#192	4. Set expiration - Payment requests should expire
#193	5. Wait for confirmations - Confirm before fulfilling
#194

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