Sanvir K.

I design and build production-ready SaaS and enterprise applications with .NET, ASP.NET Core, C#, Azure, and modern frontend frameworks.

I’m a Senior .NET Full-Stack Developer and SaaS Architect with 15+ years of experience delivering multi-tenant platforms, CRM and workflow systems, business APIs, cloud applications, and AI-enabled products.

I work with companies that need more than isolated coding tasks—teams that need a senior engineer who can understand the business workflow, choose a maintainable architecture, and deliver reliable software through production.

Recent work includes a multi-tenant call center management SaaS (Twilio, role-based access, real-time dashboards), a dispatch management platform for logistics operations, a multi-channel sales system integrating 30+ marketplaces including Amazon and eBay, and a multi-tenant scheduling SaaS where I cut data sync time from hours to about 4-5 minutes.

What I build

• Multi-tenant SaaS platforms.
• CRM, ERP, and business management systems.
• Workflow and approval automation.
• Customer portals and admin dashboards.
• Enterprise web applications and APIs.
• Booking, scheduling, and operations platforms.
• Real-time applications and background processing.
• AI-enabled business applications.
• Legacy .NET modernization and migrations.
• Cloud-native applications on Microsoft Azure.

What I can help you with
• New product architecture and development.
• ASP.NET MVC or legacy .NET modernization.
• ASP.NET Core and .NET 8 application development.
• REST, GraphQL, gRPC, and SOAP APIs.
• Third-party API and payment integrations.
• Multi-tenant architecture and role-based access control.
• Authentication with JWT, OAuth, OpenID Connect, and SSO.
• Database design, query optimization, and performance improvement.
• Azure deployment, Docker, CI/CD, and production support.
• AI features using OpenAI, Azure OpenAI, LLM APIs, semantic search, and document processing.

Core technology stack
Backend: C#, .NET, ASP.NET Core, ASP.NET MVC, Entity Framework Core, Web API.
Frontend: Angular, React, TypeScript, JavaScript.
Cloud and DevOps: Microsoft Azure, AWS, Docker, Kubernetes, Azure DevOps, CI/CD. Data: SQL Server, PostgreSQL, Redis, Entity Framework. Architecture: Clean Architecture, DDD, microservices, event-driven systems, multi-tenant SaaS. Integrations: REST, GraphQL, gRPC, SignalR, Stripe, Twilio, SendGrid, QuickBooks, payment and business APIs. AI: OpenAI, Azure OpenAI, LLM integrations, document processing, summarization, intelligent search, and automation.