Design and implement a payment-provider abstraction layer and integrate card capture, payment, and refund flows for a client-facing e-commerce application. Modernize brownfield .NET systems spanning .NET Framework 4.5.x through .NET 6+, stabilize Angular and React interfaces, remediate security issues, and minimize PCI compliance exposure. Collaborate with delivery teams and client stakeholders while documenting incomplete ownership and systems.
N-iX is a global software development service company that helps businesses across the globe create next-generation software products. Founded in 2002, we unite 2,400+ tech-savvy professionals across 40+ countries, working on impactful projects for industry leaders and Fortune 500 companies. Our expertise spans cloud, data, AI/ML, embedded software, IoT, and more, driving digital transformation across finance, manufacturing, telecom, healthcare, and other industries. Join N-iX and become part of a team where your ideas make a real impact.
We are looking for a Senior .NET Fullstack Engineer to work on migrating a client-facing e-commerce/store application's payment processing from its current gateway to a new payment provider.
Key Responsibilities- Design and implement an abstraction layer that decouples the application from a single payment provider, enabling multiple providers to operate in parallel.
- Implement the integration with the new payment provider, including the card-capture and payment/refund flows, in a way that minimizes the application's compliance exposure.
- Collaborate closely with a small delivery team and client-side stakeholders where ownership or documentation is incomplete.
- Experience: 6+ years of professional .NET development on large production systems; brownfield / legacy modernization experience is mandatory — this is not a greenfield role.
- Core stack (Must-Have): expert C# and ASP.NET (MVC, Web API, Razor Pages); hands-on with both .NET Framework 4.5.x-era code and .NET 6+ migrations; EF / EF Core.
- Frontend (Must-Have): solid Angular, React and TypeScript for upgrading and stabilizing existing UIs.
- Security mindset: practical experience remediating security findings (OWASP classes, secrets handling, crypto usage) in existing code; PCI / payments / fintech exposure is a strong plus.
- English: fluent written and spoken English (B2+) for documentation, evidence packages and client calls.
- Nice-to-Haves: Azure PaaS (App Services, Functions, Service Bus, Cosmos DB); AWS (Lambda, S3, SNS/SQS); Azure AD B2C; Blazor; SignalR; Telerik / Kendo UI.
We offer*:
- Flexible working format - remote, office-based or flexible
- A competitive salary and good compensation package
- Personalized career growth
- Professional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)
- Active tech communities with regular knowledge sharing
- Education reimbursement
- Memorable anniversary presents
- Corporate events and team buildings
- Other location-specific benefits
*not applicable for freelancers
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