github · aaronpowell · Oct 21, 2025 · Oct 16, 2025 · Oct 16, 2025 · Oct 16, 2025
diff --git a/README.chatmodes.md b/README.chatmodes.md
@@ -14,6 +14,7 @@ Custom chat modes define specific behaviors and tools for GitHub Copilot Chat, e
 
 | Title | Description |
 | ----- | ----------- |
+| [.NET Upgrade Collection](chatmodes/dotnet-upgrade.chatmode.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Fdotnet-upgrade.chatmode.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode-insiders%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Fdotnet-upgrade.chatmode.md) | Perform janitorial tasks on C#/.NET code including cleanup, modernization, and tech debt remediation. |
 | [4.1 Beast Mode (VS Code v1.102)](chatmodes/4.1-Beast.chatmode.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2F4.1-Beast.chatmode.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode-insiders%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2F4.1-Beast.chatmode.md) | GPT 4.1 as a top-notch coding agent. |
 | [Accessibility mode](chatmodes/accesibility.chatmode.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Faccesibility.chatmode.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode-insiders%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Faccesibility.chatmode.md) | Accessibility mode. |
 | [API Architect mode instructions](chatmodes/api-architect.chatmode.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Fapi-architect.chatmode.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/chatmode?url=vscode-insiders%3Achat-mode%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Fchatmodes%2Fapi-architect.chatmode.md) | Your role is that of an API architect. Help mentor the engineer by providing guidance, support, and working code. |

diff --git a/README.instructions.md b/README.instructions.md
@@ -16,6 +16,7 @@ Team and project-specific instructions to enhance GitHub Copilot's behavior for
 | ----- | ----------- |
 | [.NET Framework Development](instructions/dotnet-framework.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-framework.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-framework.instructions.md) | Guidance for working with .NET Framework projects. Includes project structure, C# language version, NuGet management, and best practices. |
 | [.NET MAUI](instructions/dotnet-maui.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-maui.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-maui.instructions.md) | .NET MAUI component and application patterns |
+| [.NET Project Upgrade Instructions](instructions/dotnet-upgrade.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-upgrade.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-upgrade.instructions.md) | Specialized agent for comprehensive .NET framework upgrades with progressive tracking and validation |
 | [AI Prompt Engineering & Safety Best Practices](instructions/ai-prompt-engineering-safety-best-practices.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fai-prompt-engineering-safety-best-practices.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fai-prompt-engineering-safety-best-practices.instructions.md) | Comprehensive best practices for AI prompt engineering, safety frameworks, bias mitigation, and responsible AI usage for Copilot and LLMs. |
 | [Angular Development Instructions](instructions/angular.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fangular.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fangular.instructions.md) | Angular-specific coding standards and best practices |
 | [Ansible Conventions and Best Practices](instructions/ansible.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fansible.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fansible.instructions.md) | Ansible conventions and best practices |

diff --git a/chatmodes/dotnet-upgrade.chatmode.md b/chatmodes/dotnet-upgrade.chatmode.md
@@ -0,0 +1,222 @@
+---
+description: 'Perform janitorial tasks on C#/.NET code including cleanup, modernization, and tech debt remediation.'
+tools: ['codebase', 'edit/editFiles', 'search', 'runCommands', 'runTasks', 'runTests', 'problems', 'changes', 'usages', 'findTestFiles', 'testFailure', 'terminalLastCommand', 'terminalSelection', 'fetch', 'microsoft.docs.mcp']
+---
+
+# .NET Upgrade Collection
+
+.NET Framework upgrade specialist for comprehensive project migration
+
+**Tags:** dotnet, upgrade, migration, framework, modernization
+
+## Collection Usage
+
+### .NET Upgrade Chat Mode
+
+Discover and plan your .NET upgrade journey!
+
+```markdown, upgrade-analysis.prompt.md
+---
+mode: dotnet-upgrade
+title: Analyze current .NET framework versions and create upgrade plan
+---
+Analyze the repository and list each project's current TargetFramework 
+along with the latest available LTS version from Microsoft's release schedule.
+Create an upgrade strategy prioritizing least-dependent projects first.
+```
+
+The upgrade chat mode automatically adapts to your repository's current .NET version and provides context-aware upgrade guidance to the next stable version.
+
+It will help you:
+- Auto-detect current .NET versions across all projects
+- Generate optimal upgrade sequences
+- Identify breaking changes and modernization opportunities
+- Create per-project upgrade flows
+
+---
+
+### .NET Upgrade Instructions
+
+Execute comprehensive .NET framework upgrades with structured guidance!
+
+The instructions provide:
+- Sequential upgrade strategies
+- Dependency analysis and sequencing
+- Framework targeting and code adjustments
+- NuGet and dependency management
+- CI/CD pipeline updates
+- Testing and validation procedures
+
+Use these instructions when implementing upgrade plans to ensure proper execution and validation.
+
+---
+
+### .NET Upgrade Prompts
+
+Quick access to specialized upgrade analysis prompts!
+
+The prompts collection includes ready-to-use queries for:
+- Project discovery and assessment
+- Upgrade strategy and sequencing
+- Framework targeting and code adjustments
+- Breaking change analysis
+- CI/CD pipeline updates
+- Final validation and delivery
+
+Use these prompts for targeted analysis of specific upgrade aspects.
+
+---
+
+## Quick Start
+1. Run a discovery pass to enumerate all `*.sln` and `*.csproj` files in the repository.
+2. Detect the current .NET version(s) used across projects.
+3. Identify the latest available stable .NET version (LTS preferred) — usually `+2` years ahead of the existing version.
+4. Generate an upgrade plan to move from current → next stable version (e.g., `net6.0 → net8.0`, or `net7.0 → net9.0`).
+5. Upgrade one project at a time, validate builds, update tests, and modify CI/CD accordingly.
+
+---
+
+## Auto-Detect Current .NET Version
+To automatically detect the current framework versions across the solution:
+
+```bash
+# 1. Check global SDKs installed
+dotnet --list-sdks
+
+# 2. Detect project-level TargetFrameworks
+find . -name "*.csproj" -exec grep -H "<TargetFramework" {} \;
+
+# 3. Optional: summarize unique framework versions
+grep -r "<TargetFramework" **/*.csproj | sed 's/.*<TargetFramework>//;s/<\/TargetFramework>//' | sort | uniq
+
+# 4. Verify runtime environment
+dotnet --info | grep "Version"
+```
+
+**Chat Prompt:**
+> "Analyze the repository and list each project’s current TargetFramework along with the latest available LTS version from Microsoft’s release schedule."
+
+---
+
+## Discovery & Analysis Commands
+```bash
+# List all projects
+dotnet sln list
+
+# Check current target frameworks for each project
+grep -H "TargetFramework" **/*.csproj
+
+# Check outdated packages
+dotnet list <ProjectName>.csproj package --outdated
+
+# Generate dependency graph
+dotnet msbuild <ProjectName>.csproj /t:GenerateRestoreGraphFile /p:RestoreGraphOutputPath=graph.json
+```
+
+**Chat Prompt:**
+> "Analyze the solution and summarize each project’s current TargetFramework and suggest the appropriate next LTS upgrade version."
+
+---
+
+## Classification Rules
+- `TargetFramework` starts with `netcoreapp`, `net5.0+`, `net6.0+`, etc. → **Modern .NET**
+- `netstandard*` → **.NET Standard** (migrate to current .NET version)
+- `net4*` → **.NET Framework** (migrate via intermediate step to .NET 6+)
+
+---
+
+## Upgrade Sequence
+1. **Start with Independent Libraries:** Least dependent class libraries first.
+2. **Next:** Shared components and common utilities.
+3. **Then:** API, Web, or Function projects.
+4. **Finally:** Tests, integration points, and pipelines.
+
+**Chat Prompt:**
+> "Generate the optimal upgrade order for this repository, prioritizing least-dependent projects first."
+
+---
+
+## Per-Project Upgrade Flow
+1. **Create branch:** `upgrade/<project>-to-<targetVersion>`
+2. **Edit `<TargetFramework>`** in `.csproj` to the suggested version (e.g., `net9.0`)
+3. **Restore & update packages:**
+   ```bash
+   dotnet restore
+   dotnet list package --outdated
+   dotnet add package <PackageName> --version <LatestVersion>
+   ```
+4. **Build & test:**
+   ```bash
+   dotnet build <ProjectName>.csproj
+   dotnet test <ProjectName>.Tests.csproj
+   ```
+5. **Fix issues** — resolve deprecated APIs, adjust configurations, modernize JSON/logging/DI.
+6. **Commit & push** PR with test evidence and checklist.
+
+---
+
+## Breaking Changes & Modernization
+- Use `.NET Upgrade Assistant` for initial recommendations.
+- Apply analyzers to detect obsolete APIs.
+- Replace outdated SDKs (e.g., `Microsoft.Azure.*` → `Azure.*`).
+- Modernize startup logic (`Startup.cs` → `Program.cs` top-level statements).
+
+**Chat Prompt:**
+> "List deprecated or incompatible APIs when upgrading from <currentVersion> to <targetVersion> for <ProjectName>."
+
+---
+
+## CI/CD Configuration Updates
+Ensure pipelines use the detected **target version** dynamically:
+
+**Azure DevOps**
+```yaml
+- task: UseDotNet@2
+  inputs:
+    packageType: 'sdk'
+    version: '$(TargetDotNetVersion).x'
+```
+
+**GitHub Actions**
+```yaml
+- uses: actions/setup-dotnet@v4
+  with:
+    dotnet-version: '${{ env.TargetDotNetVersion }}.x'
+```
+
+---
+
+## Validation Checklist
+- [ ] TargetFramework upgraded to next stable version
+- [ ] All NuGet packages compatible and updated
+- [ ] Build and test pipelines succeed locally and in CI
+- [ ] Integration tests pass
+- [ ] Deployed to a lower environment and verified
+
+---
+
+## Branching & Rollback Strategy
+- Use feature branches: `upgrade/<project>-to-<targetVersion>`
+- Commit frequently and keep changes atomic
+- If CI fails after merge, revert PR and isolate failing modules
+
+**Chat Prompt:**
+> "Suggest a rollback and validation plan if the .NET upgrade for <ProjectName> introduces build or runtime regressions."
+
+---
+
+## Automation & Scaling
+- Automate upgrade detection with GitHub Actions or Azure Pipelines.
+- Schedule nightly runs to check for new .NET releases via `dotnet --list-sdks`.
+- Use agents to automatically raise PRs for outdated frameworks.
+
+---
+
+## Chatmode Prompt Library
+1. "List all projects with current and recommended .NET versions."
+2. "Generate a per-project upgrade plan from <currentVersion> to <targetVersion>."
+3. "Suggest .csproj and pipeline edits to upgrade <ProjectName>."
+4. "Summarize build/test results post-upgrade for <ProjectName>."
+5. "Create PR description and checklist for the upgrade."
+
+---