[Remote] Principal .NET Software Engineer - Cloud Payments Platform

Note: The job is a remote job and is open to candidates in USA. Versapay is a company that transforms accounts receivable into a competitive advantage. They are seeking an experienced .NET Principal Software Engineer to modernize their payments infrastructure, improve scalability and security, and design new distributed services, while taking ownership of critical payment services and collaborating with various teams to enhance customer experience.ResponsibilitiesOwn and evolve core payment services for online (CNP), device-based EMV (CP), digital wallets (e.g., Apple Pay, Google Pay), and payment facilitator/orchestration flowsModernize and improve existing components into more cloud-native, distributed architectures using containers on AWS/AzureOwn and extend end-to-end payment workflows: authorization, capture, void, refund, tokenization, clearing, funding, settlement, and multi-source reconciliationExpand capabilities for international payments, including multi-currency and cross-border flowsIntegrate with payment service providers (PSPs), EMV card readers, and device SDKs using secure, standards-based messagingImprove and maintain CI/CD pipelines in GitHub Actions (automated builds, tests, security scans, packaging, deployments)Design and evolve test automation strategy, covering domain-level logic, API contracts, and integration with external processors and devicesStrengthen platform reliability through observability (metrics, logs, traces), fault-tolerant design, and automated operational workflowsPartner with Product, Security, Compliance, and Operations to deliver features that balance customer experience, regulatory requirements, risk, and operational robustnessMentor engineers, lead design and architecture discussions, and influence the long-term strategy for the payments platformSkillsSignificant experience (typically 10+ years) of professional engineering with expert proficiency in C#, .NET, and SQLDeep experience in payments: online payments, EMV device-based transactions, digital wallets (e.g., Apple Pay, Google Pay), PayFac/orchestration flows, bank account rails (ACH/EFT), and international/multi-currency payment flowsProven ability to modernize production financial systems into cloud-native, distributed architecturesFamiliarity with monitoring and observing distributed systems using modern observability toolingProven ability to work cross-functionally with Product, Security, Compliance, and Operations, and to represent engineering effectively to non-technical stakeholdersExperience using AI-assisted development tools to enhance productivity and code qualityStrong Knowledge Of: Modern API and integration design (RESTful services), asynchronous messaging/queueing, caching, event-driven architecture, high-availability patternsStrong Knowledge Of: AWS or Azure, containerization, orchestration, and CI/CD automationStrong Knowledge Of: PCI-DSS, encryption, tokenization, key-rotation, and secure coding principlesExperience with multi-region cloud architecture and distributed data patternsExperience with modern UX/front-end development (e.g., JavaScript/TypeScript)Deep Hands-on Experience With Several Of The Following: ISO 8583 transaction messagingDeep Hands-on Experience With Several Of The Following: ISO 20022 data models and payment messagingDeep Hands-on Experience With Several Of The Following: DUKPT key-management and secure device cryptographyDeep Hands-on Experience With Several Of The Following: Hardware Security Modules (HSMs) and secure key lifecycleDeep Hands-on Experience With Several Of The Following: EMV payment kernels and card/device authentication flowsCompany OverviewVersapay is a Fintech company offering an accounts receivable efficiency suite that simplifies the invoice-to-cash process. It was founded in 2006, and is headquartered in Miami, Florida, USA, with a workforce of 201-500 employees. Its website is http://www.versapay.com.Company H1B SponsorshipVersapay has a track record of offering H1B sponsorships, with 2 in 2024, 1 in 2023, 1 in 2021. Please note that this does not guarantee sponsorship for this specific role.