Senior Backend Engineer - Payments (Go, TypeScript, Node.js)

SPD Technology is a global software product development company specializing in fintech and digital payment solutions, data engineering, AI/ML, and cloud technologies. Founded in 2006, it has delivered over 460 custom projects for high-growth startups, SMBs, and enterprises worldwide, partnering with Fortune 500 firms and emerging startups. The company has over 650 engineers across 35 countries, with main expertise in fintech and digital payments. Four of its clients generate over $4B in annual revenue each.

• 6+ years of professional software engineering experience.
• At least 3 years of hands-on experience with payment systems or payment processing.
• Strong backend engineering experience with Go, TypeScript, and Node.js.
• Direct experience owning production payment flows beyond basic payment API integrations.
• Experience integrating payment processors or acquirers such as Stripe, Adyen, Braintree, Checkout.com, Worldpay, Fiserv, or similar.
• Strong understanding of card payment lifecycle: authorization, capture, settlement, refunds, chargebacks, disputes.
• Understanding of bank payment rails and ACH/NACHA concepts including returns and timing.
• Experience with payment reconciliation and settlement.
• Strong understanding of webhooks, retries, idempotency, asynchronous processing, and distributed-system failure scenarios.
• Experience designing relational data models for transaction-heavy systems.
• Understanding of PCI DSS and payment-security patterns like tokenization and isolation of sensitive payment data.
• Strong attention to correctness and handling edge cases in financial systems.
• Fluency with modern AI-assisted development tooling.
• Strong English communication skills and confidence working directly with a US-based team.
• Ability to work with 4–6 hours of daily overlap with US Central Time.

• Own end-to-end payment flows in TypeScript/NestJS services including authorization, capture, void, refund, dispute handling, and payout initiation and confirmation.
• Build and maintain acquirer and processor integrations, maintaining acquirer-agnostic abstractions.
• Design embedded and hosted checkout experiences that keep sensitive data out of internal systems and reduce PCI scope.
• Implement fee calculation and rate logic including tiers, interchange-plus, flat structures, rounding rules, and special cases.
• Build reconciliation and settlement layers matching processor reports and settlement files.
• Design event handling with idempotency keys, handling out-of-order and duplicate webhooks, retries with backoff, and state machines.
• Integrate fraud, bank-account verification, and KYC providers with tuned decisioning based on real outcomes.
• Handle ACH mechanics including submission windows, returns, return codes, NOCs, and retry rules.
• Ensure domain correctness with complete audit trails and reconciliation evidence.
• Act as the payments expert advising product on rail capabilities and reviewing payment-adjacent code.