Modernize intelligent apps and agents with .NET that scale as you grow | OD801
Andrew Westgarth and Gaurav Seth explain how to modernize legacy .NET applications using Managed Instance on Azure App Service, focusing on removing migration blockers without code rewrites and moving to a scalable PaaS foundation. They also show how GitHub Copilot can support AI-assisted modernization and MCP-driven API interactions.
Overview
This Microsoft Build 2026 session covers a modernization approach for existing .NET applications that need to scale, reduce operational overhead, and keep legacy dependencies intact.
Key themes include:
- Using Managed Instance on Azure App Service to modernize legacy .NET apps without a full rewrite
- Addressing common legacy modernization blockers (especially dependency constraints)
- Applying agentic application patterns and modular design concepts
- Using GitHub Copilot for AI-assisted modernization workflows
- Secure connectivity and operational capabilities on App Service (including Bastion, scaling, and resiliency)
- Using GitHub Copilot to access an MCP server and interact with REST APIs
Session chapters (from the video)
Overview of Managed Instance on Azure App Service
- Introduces Managed Instance on Azure App Service as a path to move legacy .NET workloads to a scalable PaaS foundation.
Understanding modernization challenges: legacy system dependencies
- Discusses how legacy apps often have dependencies that make migrations difficult.
- Positions Managed Instance on App Service as a way to retain dependencies while removing blockers that typically force rewrites.
Agentic application patterns and modular design
- Covers patterns for building or evolving applications toward agentic and more modular architectures.
GitHub Copilot for AI-assisted app modernization
- Shows how GitHub Copilot can be used to support modernization work, including guidance and assistance during refactoring and migration-related tasks.
Demo: modernizing a .NET app with GitHub Copilot
- Walks through a demo flow for modernizing a .NET application using GitHub Copilot.
Provisioning and automatic deployment overview
- Describes the provisioning process and how deployment can be automated as part of the modernization approach.
Secure remote connectivity via Bastion for Managed Instance on App Service
- Demonstrates using Azure Bastion to enable secure remote connectivity to the managed environment.
Scaling, deployment slots, authentication, and resiliency options on App Service
- Reviews operational capabilities available on Azure App Service, including:
- Scaling
- Deployment slots
- Authentication options
- Resiliency considerations
Using GitHub Copilot to access an MCP server and interact with REST APIs
- Demonstrates GitHub Copilot being used to connect to an MCP server and work with REST APIs as part of the workflow.