Build ASP.NET applications

Blue Agent provides ASP.NET Core runtime pre-installed across all container flavors. The project includes ASP.NET Core 8.0 runtime by default, but development teams can install specific SDK versions as needed for their build requirements.

What’s pre-installed

All Blue Agent container images include:

• ASP.NET Core 8.0 Runtime: Available across all Linux flavors
• ASP.NET Core 8.0 SDK: Available in Windows flavors

The runtime-only approach for Linux containers keeps the image size minimal while providing the necessary components for running ASP.NET applications.

Recommended approach

It is strongly recommended that development teams specify the exact .NET version they require in their pipeline. This approach ensures:

• Reproducible builds: Same environment across all pipeline runs
• Developer control: Teams choose when to upgrade, not the platform
• Consistency: Predictable behavior across different agent instances

Install specific SDK versions

For building ASP.NET applications, install the specific SDK version using UseDotNet@2:

# azure-pipelines.yaml
steps:
  # Cache NuGet packages for faster builds
  - task: Cache@2
    inputs:
      key: 'nuget | "$(Agent.OS)" | **/packages.lock.json'
      restoreKeys: |
        nuget | "$(Agent.OS)"
      path: $(Pipeline.Workspace)/.nuget/packages
    displayName: Cache NuGet packages

  # Install specific .NET SDK version
  - task: UseDotNet@2
    inputs:
      packageType: sdk
      version: 8.0.x
    displayName: Install .NET SDK 8.0.x

  # Restore dependencies
  - script: dotnet restore
    displayName: Restore NuGet packages

Multi-targeting scenarios

For projects requiring multiple .NET versions, install each version sequentially:

steps:
  - task: UseDotNet@2
    inputs:
      packageType: sdk
      version: 6.0.x
    displayName: Install .NET SDK 6.0.x

  - task: UseDotNet@2
    inputs:
      packageType: sdk
      version: 8.0.x
    displayName: Install .NET SDK 8.0.x

  - script: dotnet build --configuration Release --framework net6.0
    displayName: Build for .NET 6.0

  - script: dotnet build --configuration Release --framework net8.0
    displayName: Build for .NET 8.0