How to Build a PayPal Alternative with a Global Payments API
An architecture guide for a wallet-and-payments platform with a ledger, funding rails, checkout, payouts, disputes, risk, FX, and developer APIs.
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Payment Api
Design patterns for payment intents, resources, state machines, idempotency, and developer contracts.
World Chain Payment API Guide: Mini Apps, WLD, and Stablecoin Flows
A developer-focused guide to payment flows in World App and World Chain, including Mini Apps, WLD, stablecoins, gas sponsorship, verification, and refunds.
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Crypto Invoice API for Bitcoin, Ethereum, and Solana: A Practical Design
Design a multi-chain crypto invoice API with quotes, addresses, confirmations, webhooks, refunds, and chain-aware reconciliation.
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ACH and Direct Deposit API Design: Files, Returns, and Reconciliation
A practical design for ACH credits and debits, direct deposit, authorization evidence, return handling, idempotency, and bank-grade reconciliation.
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USDT Payment Processing Guide: Networks, Treasury, and Risk Controls
How to design USDT collection, confirmation, treasury, reconciliation, and exception workflows without treating every token or network as interchangeable.
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USDC Payment API Integration Guide: From Intent to Reconciliation
A step-by-step guide to USDC payment intents, deposit addresses, network selection, confirmations, refunds, webhooks, and treasury operations.
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Stablecoin Payment API Architecture: A Production-Ready Blueprint
A practical architecture for payment intents, chain abstraction, confirmations, webhooks, compliance controls, and reconciliation across stablecoin rails.
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Explore all 10 implementation guides and their related payment architecture pages.