Payments guides

Every guide, concept, and reference under the Payments tab, grouped by what you're trying to do.

Send and transfer

• Send your first USDT0 — Native and ERC-20 transfers on the same balance.
• Zero gas transactions — Transfer USDT0 with the fee covered by a Gas Waiver.
• Work with USDT0 as gas — Construct transactions correctly: priority tip 0, value in USDT0.
• Bridge USDT0 to Stable — Bridge from Ethereum Sepolia using LayerZero OFT.

Build a payment flow

• Learn P2P payments — Wallet + send + receive + history in one app.
• Subscribe and collect — Pull-based recurring billing via EIP-7702.
• Paying with invoice — ERC-3009 with deterministic nonces for invoice settlement.
• Build a pay-per-call API — Monetise HTTP endpoints with x402 middleware.

Protocols and references

• ERC-3009 — Transfer With Authorization: the signed-settlement primitive.
• x402 (HTTP-native payments) — Server responds 402, client signs, facilitator settles on-chain.
• P2P payments reference — Model overview and comparison to traditional rails.
• Subscriptions reference — Pull-based billing model and trade-offs.
• Invoices reference — Deterministic-nonce settlement model.
• Pay-per-call reference — x402 pricing and endpoint discovery model.
• Upcoming use cases — Guaranteed settlement, confidential payments, agent-to-agent.