post: upgrading seedfolder to .NET 10 LTS

solrevdev · solrevdev · commit 88e8925d1bb4 · 2025-11-14T11:14:50.000Z
Add blog post documenting the process of upgrading SeedFolder to support .NET 10 while maintaining backward compatibility with .NET 8 and 9. Covers: - Multi-targeting strategy - Dependency management - CI/CD pipeline updates - Testing approach - Best practices for .NET global tools Related to: solrevdev/seedfolder#17
diff --git a/_posts/2025-11-14-upgrading-seedfolder-to-dotnet-10-lts.md b/_posts/2025-11-14-upgrading-seedfolder-to-dotnet-10-lts.md
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+---
+layout: post
+title: Upgrading SeedFolder to .NET 10 LTS - Maintaining Multi-Target Framework Support
+description: How to upgrade a .NET Global Tool to support .NET 10 while maintaining backward compatibility with .NET 8 and 9
+summary: A walkthrough of upgrading SeedFolder to support .NET 10 (LTS) while maintaining full backward compatibility with .NET 8 and 9. Covers multi-targeting, dependency management, CI/CD updates, and testing strategies for .NET global tools.
+cover_image: /images/seedfolder-dotnet10-upgrade.svg
+tags:
+- dotnet-global-tools
+- dotnet
+- csharp
+- dotnet10
+- multi-targeting
+- nuget
+- ci-cd
+
+---
+**Overview** ☀
+
+With .NET 10 now released as the latest Long-Term Support (LTS) version, it was time to update [SeedFolder](https://github.com/solrevdev/seedfolder) to support the newest framework while maintaining compatibility with .NET 8 and 9. This post walks through the process of adding .NET 10 support to a global tool, managing dependencies, updating CI/CD pipelines, and ensuring a smooth upgrade path for users.
+
+**Why .NET 10?** 🎯
+
+.NET 10 is the latest LTS release, providing long-term support until November 2028. By adding .NET 10 support alongside existing .NET 8 and 9 targets, SeedFolder users get:
+
+- **Latest LTS**: Long-term support until November 2028
+- **Performance improvements**: Built-in performance enhancements from .NET 10
+- **Forward compatibility**: Automatic use of the highest installed SDK
+- **Backward compatibility**: Continued support for .NET 8 (LTS) and .NET 9 (STS)
+
+The beauty of multi-targeting is that users with any of these SDK versions can install and run the tool. When multiple SDKs are installed, the .NET CLI automatically selects the highest compatible version.
+
+**The Upgrade Process** 🚀
+
+The upgrade was surprisingly straightforward, thanks to .NET's excellent multi-targeting support. Here's the step-by-step process I followed:
+
+**1. Research and Planning** 📚
+
+Before making any changes, I researched the .NET 10 requirements:
+
+- **Target Framework Moniker (TFM)**: `net10.0`
+- **SDK Version**: `10.0.100` or later
+- **Breaking Changes**: Reviewed Microsoft docs for any breaking changes (none affecting SeedFolder)
+
+I also reviewed the git history to understand how previous SDK upgrades were handled:
+
+```bash
+git log --all --grep=".NET" --oneline | head -20
+```
+
+This showed that the last major upgrade ([PR #259c452](https://github.com/solrevdev/seedfolder/commit/259c45284d67cb8ab6b1ff2f65d9fe2c5bfa8223)) added .NET 8 and 9 support, following a similar pattern I could replicate.
+
+**2. Update Project File** 🔧
+
+The key change was adding `net10.0` to the `TargetFrameworks` property in the `.csproj` file:
+
+```diff
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+-   <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
++   <TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
+    <LangVersion>latest</LangVersion>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <PackAsTool>true</PackAsTool>
+    <ToolCommandName>seedfolder</ToolCommandName>
+    <PackageOutputPath>./nupkg</PackageOutputPath>
+    <NoDefaultExcludes>true</NoDefaultExcludes>
+-   <Version>1.3.3</Version>
++   <Version>1.4.0</Version>
+    <!-- ... other properties ... -->
+  </PropertyGroup>
+</Project>
+```
+
+**Important considerations:**
+- Use semicolon-separated list for multiple targets
+- Bump the version number for NuGet release (1.3.3 → 1.4.0)
+- Maintain existing targets for backward compatibility
+
+**3. Update CI/CD Pipeline** ⚙️
+
+The GitHub Actions workflow needed to install the .NET 10 SDK alongside existing versions:
+
+```diff
+- name: setup .net core sdk
+  uses: actions/setup-dotnet@v4
+  with:
+      dotnet-version: |
+        8.0.x
+        9.0.x
++       10.0.x
+```
+
+This ensures the CI pipeline can build all three target frameworks.
+
+**4. Dependency Management** 📦
+
+I ran `dotnet outdated` to check for package updates:
+
+```bash
+dotnet tool install -g dotnet-outdated-tool
+dotnet outdated
+```
+
+This revealed that Figgle (the ASCII art library) had a newer version (0.6.5). However, upon investigation, version 0.6.x introduced breaking changes by splitting fonts into a separate package. Since the upgrade goal was .NET 10 support, not dependency updates, I kept Figgle at 0.5.1 to avoid unnecessary complexity.
+
+**5. Build and Test** ✅
+
+Building for multiple frameworks is straightforward with multi-targeting:
+
+```bash
+dotnet build solrevdev.seedfolder.sln --configuration Release
+```
+
+Output showed successful builds for all three targets:
+
+```
+solrevdev.seedfolder -> src/bin/Release/net8.0/solrevdev.seedfolder.dll
+solrevdev.seedfolder -> src/bin/Release/net9.0/solrevdev.seedfolder.dll
+solrevdev.seedfolder -> src/bin/Release/net10.0/solrevdev.seedfolder.dll
+```
+
+**Testing the Tool Locally** 🧪
+
+Before publishing, I packaged and tested the tool locally:
+
+```bash
+# Package the tool
+dotnet pack -c Release -o /tmp/seedfolder-test
+
+# Install from local package
+dotnet tool uninstall -g solrevdev.seedfolder
+dotnet tool install -g --add-source /tmp/seedfolder-test solrevdev.seedfolder
+
+# Verify installation
+seedfolder --version
+# Output: seedfolder version 1.4.0
+```
+
+Then I tested various commands in `/tmp` to ensure functionality:
+
+```bash
+# Test dry-run mode
+seedfolder --dry-run -t node test-node-app
+
+# Create Python project
+seedfolder -t python test-python-app
+
+# Create .NET project
+seedfolder --template dotnet test-dotnet-app
+
+# Verify help and template listing
+seedfolder --help
+seedfolder --list-templates
+```
+
+All tests passed successfully! 🎉
+
+**6. Update Documentation** 📝
+
+Documentation updates included:
+
+**README.md** - Updated requirements section:
+```diff
+## Requirements
+
+- This tool requires **.NET 8.0 or .NET 9.0 SDK** to be installed
++ This tool requires **.NET 8.0, .NET 9.0, or .NET 10.0 SDK** to be installed
+
+- **Runtime**: .NET 8.0 or later
+```
+
+**CLAUDE.md** - Updated framework information:
+```diff
+## Multi-Target Framework Support
+- The project targets .NET 8.0 (LTS) and 9.0 (STS)
++ The project targets .NET 8.0 (LTS), 9.0 (STS), and 10.0 (LTS)
++ .NET 10 is the latest LTS release providing long-term support until November 2028.
+```
+
+**Multi-Targeting Best Practices** 💡
+
+From this experience, here are some best practices for multi-targeting .NET global tools:
+
+**1. Use Multi-Targeting, Not Multiple Projects**
+```xml
+<!-- Good: Single project, multiple targets -->
+<TargetFrameworks>net8.0;net9.0;net10.0</TargetFrameworks>
+
+<!-- Bad: Multiple projects for different versions -->
+```
+
+**2. Maintain LTS Versions**
+
+Keep the previous LTS version (net8.0) alongside the new one. This gives users flexibility and ensures broad compatibility.
+
+**3. Test All Targets**
+
+The NuGet package includes all target frameworks:
+
+```
+tools/net8.0/any/solrevdev.seedfolder.dll
+tools/net9.0/any/solrevdev.seedfolder.dll
+tools/net10.0/any/solrevdev.seedfolder.dll
+```
+
+Verify each target builds correctly and the tool runs on all supported SDKs.
+
+**4. Handle Dependencies Carefully**
+
+When upgrading, check if dependencies support all your target frameworks. If a dependency doesn't support your newest target, you have options:
+
+- Keep the dependency at a compatible version
+- Use conditional package references for different targets
+- Find an alternative package
+
+**5. Update CI/CD First**
+
+Install all SDK versions in your CI pipeline before merging. This catches incompatibilities early:
+
+```yaml
+- name: setup .net core sdk
+  uses: actions/setup-dotnet@v4
+  with:
+      dotnet-version: |
+        8.0.x
+        9.0.x
+        10.0.x
+```
+
+**The Results** 📊
+
+After merging [PR #17](https://github.com/solrevdev/seedfolder/pull/17), the CI/CD pipeline automatically:
+
+1. Built all three target frameworks
+2. Ran integration tests
+3. Packaged the NuGet package
+4. Published version 1.4.0 to NuGet
+
+Users can now install the updated version:
+
+```bash
+dotnet tool update --global solrevdev.seedfolder
+seedfolder --version
+# Output: seedfolder version 1.4.0
+```
+
+The tool automatically uses the highest installed SDK when run, so users with .NET 10 get the latest performance improvements while users on .NET 8 or 9 continue to work seamlessly.
+
+**Framework Support Timeline** 📅
+
+Current support timeline for SeedFolder:
+
+| Framework | Type | Support Until | Status |
+|-----------|------|---------------|--------|
+| .NET 8.0  | LTS  | November 2026 | ✅ Supported |
+| .NET 9.0  | STS  | 18 months     | ✅ Supported |
+| .NET 10.0 | LTS  | November 2028 | ✅ Supported |
+
+**Lessons Learned** 🎓
+
+1. **Multi-targeting is powerful**: Adding .NET 10 support while maintaining .NET 8 and 9 compatibility was trivial thanks to proper multi-targeting setup.
+
+2. **Dependency management matters**: Always check dependencies when upgrading. Sometimes staying on older (but stable) dependency versions is the right choice.
+
+3. **Testing is essential**: Local testing before publishing caught issues that automated tests might miss.
+
+4. **Documentation updates are important**: Users need to know what versions are supported and what's changed.
+
+5. **CI/CD automation pays off**: Once configured properly, the entire build-test-publish pipeline runs automatically on merge.
+
+**What's Next?** 🔮
+
+With .NET 10 support in place, SeedFolder is well-positioned for the future. The next areas of focus include:
+
+- Template marketplace functionality ([Issue #15](https://github.com/solrevdev/seedfolder/issues/15))
+- Additional project templates based on community feedback
+- Enhanced template customization options
+
+The full source code and history of this upgrade are available on [GitHub](https://github.com/solrevdev/seedfolder/pull/17).
+
+**Installation** 📦
+
+Try the latest version with .NET 10 support:
+
+```bash
+# Install or update to the latest version
+dotnet tool update --global solrevdev.seedfolder
+
+# Create a new project with your favorite template
+seedfolder --template python my-new-project
+
+# Or use interactive mode
+seedfolder
+```
+
+Success! 🎉
