Building a Production NuGet Pipeline with Azure DevOps

When we extracted our IoT telemetry protocol parser into a standalone NuGet package, we needed a pipeline that publishes stable releases from master and prerelease packages from feature branches - automatically, with proper semantic versioning.

The Goal

Merges to master produce stable versions like 1.2.0. Merges to develop produce 1.2.0-beta.42. Feature branches produce 1.2.0-feature-gps-parser.42.

The Cross-Stage Variable Problem

Azure DevOps multi-stage pipelines have a subtle gotcha: variables set in one stage are not automatically available in subsequent stages. The fix is isOutput=true combined with stageDependencies:

# In the Version stage
- script: |
    echo "##vso[task.setvariable variable=pkgVersion;isOutput=true]$(version)"
  name: setVersion

# In the Build stage
variables:
  packageVersion: $[stageDependencies.Version.ComputeVersion.outputs['setVersion.pkgVersion']]

The syntax is stageDependencies.{Stage}.{Job}.outputs['{Step}.{Variable}'].

Branch-Based Versioning

trigger:
  branches:
    include: [master, develop, feature/*]

stages:
  - stage: Version
    jobs:
      - job: ComputeVersion
        steps:
          - script: |
              BASE=$(grep -oP '(?<=<Version>).*(?=</Version>)' src/*.csproj)
              BRANCH=$(echo $BUILD_SOURCEBRANCH | sed 's|refs/heads/||')
              if [ "$BRANCH" = "master" ]; then
                VERSION="$BASE"
              else
                SUFFIX=$(echo $BRANCH | sed 's|feature/||;s|/|-|g')
                VERSION="$BASE-$SUFFIX.$BUILD_BUILDID"
              fi
              echo "##vso[task.setvariable variable=pkgVersion;isOutput=true]$VERSION"
            name: setVersion

Key Lessons

• isOutput=true is mandatory for cross-stage variables
• Use stageDependencies, not dependencies
• Test YAML changes on feature branches first
• Pin your .NET SDK version in global.json

Internal packages deserve the same CI/CD rigor as your main applications.

Need DevOps pipelines for .NET? Get in touch.