I architect and maintain modular, production-grade financial abstractions engineered to eliminate double-charging, guarantee ACID consistency, enforce strict Address Verification Systems (AVS), and orchestrate complex settlement lifecycles at scale:

• 💳 checkout-core — High-reliability transactional payment processing engine with ACID compliance, AVS postal/street risk validation, ISO-3166 region mapping, and cryptographic idempotency.
• 💸 payout-engine — Automated disbursement and batch settlement gateway built for Go runtime environments, featuring distributed retry queues, multi-phase commit (2PC), and scheduled rolling reserves.
• 🛡️ refund-guard — Idempotent dispute and chargeback management middleware supporting real-time webhook state synchronization, SHA-256 cryptographic audit ledgers, and automated balance protection.

• Languages & Runtimes: TypeScript, Node.js, Go (Golang), SQL, Modern JavaScript (ESNext).
• Distributed Systems & State: PostgreSQL (Serializable/Repeatable Read ACID Isolation), Redis Enterprise (Distributed Locking & BullMQ Clusters), Kafka/RabbitMQ Event Streams.
• Payment Gateways & Compliance: Stripe API (PaymentIntents & Connect), Adyen Webhooks, PCI-DSS Scope Reduction Architecture, AVS & Fraud Mitigation Policies, ISO-4217 Currency Standards.
• Reliability & Observability: OpenTelemetry Tracing, Structured JSON Logging (Pino/Winston), Automated Integration Test Sandboxes, CI/CD Pipeline Hardening.

Building financial-grade infrastructure requires rigorous edge-case testing, continuous vulnerability audits, and automated integration testing against complex payment gateway sandboxes.

Your sponsorship directly fuels:

• 🛠️ Maintenance of production-ready, zero-dependency modules for modern e-commerce architectures.
• 🔒 Zero-day security patching, strict dependency auditing, and compliance research.
• ⚡ Continuous integration environments and robust mock webhook test suites.

👉 Become a GitHub Sponsor to support ongoing open-source maintenance