Senior C# .NET Developer for SaaS Platform, Azure & Microservices

We are a growing B2B SaaS company, and we're looking for a Senior .NET Architect for a paid consultation on our platform's architecture and our upcoming migration. About our product Our platform is a web application for managing client portals, documents and workflows. It's built on ASP.NET (.NET Framework 4.8) with a SQL Server database. The frontend is mixed: older pages use jQuery/JavaScript, and newer modules are in React. We also have a small Windows desktop application that some customers use for document uploads. As we grow, we are running into problems with performance, deployments and scaling. We want to move to .NET Core / ASP.NET Core and to Azure, but first we need an expert opinion on the right approach. What we need help with Reviewing our current architecture and codebase, and identifying the main risks and bottlenecks A legacy modernization strategy: a phased migration from .NET Framework to .NET Core, or a rewrite, plus the trade-offs of each Cloud development recommendations: Azure App Service vs. containers, Azure Functions for background jobs, and Azure SQL Deciding whether to break the monolith into microservices or keep a modular monolith API development best practices: a REST API design for our public API and third-party API integration (CRM, payment gateway) Frontend direction: keep React, consider Blazor, or a hybrid approach Optional: how to integrate AI features (document classification, smart search) into our SaaS platform Deliverables 2–3 consultation calls (60–90 min each) A written architecture recommendation with a target-state diagram A step-by-step migration roadmap with rough effort estimates A list of quick wins we can implement right away Requirements 7+ years with C# and .NET, including recent hands-on work with ASP.NET Core Proven experience migrating legacy .NET applications to .NET Core and Azure Strong knowledge of SaaS architecture: multi-tenancy, scalability and security Experience with SQL Server performance and data migration Ability to explain technical decisions clearly to non-technical stakeholders Nice to have Experience with FinTech or payment integrations (Stripe, Adyen, etc.) Background in CRM, portal, document management or workflow system projects AWS experience, for comparison Full stack experience with React or Angular .NET MAUI / cross-platform experience, since we may replace the desktop app with a mobile app later Engagement Hourly, around 10–15 hours to start If the consultation goes well, there's a strong chance of a long-term contract to lead the migration Timezone: at least 3–4 hours overlap with CET To apply, please answer: Describe a .NET Framework → .NET Core migration you led. What was the approach and the result? In your opinion, when do microservices make sense for a SaaS product, and when don't they? Share 1–2 relevant projects (SaaS, Azure, legacy modernization). Generic proposals will be ignored. Please start your proposal with the word ""Architecture"" so we know you've read this.