Azure DevOps Pipelines YAML Conventions

Follow these conventions when creating or modifying Azure DevOps Pipelines YAML to produce pipelines that are secure, maintainable, and performant.

Note: This skill focuses on YAML pipeline authoring conventions and best practices. For Azure Pipelines service reference documentation, see the azure-pipelines skill. For Azure DevOps CLI commands, see the azure-devops-cli skill.

General Guidelines

• Use YAML syntax with 2-space indentation consistently across all pipeline files
• Give every pipeline, stage, job, and step a meaningful name or displayName so the run UI is easy to scan
• Handle errors explicitly with condition, continueOnError, and status-check functions (succeeded(), failed(), always())
• Parameterize with variables and runtime parameters so pipelines are reusable without duplication
• Follow least-privilege for service connections -- grant only the permissions each pipeline actually needs

Pipeline Structure

Stages, Jobs, and Steps

• Use stages to represent major phases (Build, Test, Deploy-Dev, Deploy-Staging, Deploy-Prod) -- they appear as visual gates in the UI
• Use jobs within stages to group related work and enable parallel execution
• Use steps for individual tasks within a job
• Define dependsOn between stages and jobs to express ordering and fan-in/fan-out patterns
• Use condition at every level for conditional execution based on branch, variable, or prior outcome

Templates and Modularity

• Extract common patterns into templates (stages, jobs, steps, variables) and reference them with template:
• Store shared templates in a dedicated repository and consume via resources: repositories
• Use extends templates for enforcing organizational standards (required stages, security scans)
• Version templates by branch or tag so consumers can pin to a known-good version

For detailed pipeline structure guidance and examples, see references/pipeline-structure.md.

Build Best Practices

• Specify explicit agent pool and VM image versions rather than relying on latest -- this prevents surprise breakage when images update
• Cache package manager dependencies (Cache@2 task) to reduce restore times
• Publish build artifacts with PublishBuildArtifacts@1 or PublishPipelineArtifact@1 and set retention policies
• Use build variables for versioning (e.g., $(Build.BuildId), semantic version via a variable or script)
• Include code quality gates: linting, static analysis, security scans -- fail the build on violations
• For IaC pipelines, validate templates in the build stage before deployment (e.g., az bicep build --file main.bicep) to catch syntax and type errors early

Testing Integration

• Run unit tests early in the pipeline and publish results in standard formats (JUnit XML, VSTest TRX)
• Use PublishTestResults@2 with testResultsFormat set appropriately
• Collect and publish code coverage with PublishCodeCoverageResults@2
• Run integration and E2E tests in dedicated stages after deployment to a test environment
• Set failTaskOnFailedTests: true to fail the pipeline on test failures rather than silently continuing

For detailed testing patterns and examples, see references/testing.md.

Security

• Store secrets in Azure Key Vault and access them via the AzureKeyVault@2 task -- never hardcode secrets in YAML
• Use variable groups linked to Key Vault for centralized secret management
• Grant service connections the minimum permissions required; prefer managed identities over service principals with client secrets
• Integrate security scanning: dependency checking (e.g., OWASP, WhiteSource), static analysis (e.g., SonarQube, Roslyn analyzers)
• Configure approval gates and checks on environments before production deployments
• Use branch control checks on environments to restrict which branches can deploy

For detailed security guidance and Key Vault examples, see references/security.md.

Deployment Strategies

• Promote through environments sequentially: dev, staging, production
• Use deployment jobs (deployment:) with environment: targeting for deployment tracking and approvals
• Implement appropriate strategies: runOnce, rolling, canary via the strategy: block
• Include health checks and smoke tests after each deployment; roll back automatically on failure
• Manage infrastructure as code (ARM templates, Bicep, Terraform) within the pipeline

For detailed deployment patterns and rollback examples, see references/deployment.md.

Variable and Parameter Management

• Use variable groups for configuration shared across pipelines (connection strings, feature flags)
• Use runtime parameters (parameters:) to accept input at queue time for flexibility
• Apply condition with variable values for conditional logic
• Mark sensitive variables as isSecret: true in variable groups or use Key Vault references
• Use variable templates to share variable definitions across pipelines without duplication
• Use a dedicated variables.yml template file for environment-specific values (service connections, subscription IDs, environment names) and import it with template: variables.yml

For detailed variable and parameter patterns, see references/variables-and-parameters.md.

Cross-Stage Variable Passing

Passing outputs between stages and jobs is essential for IaC pipelines where deployment outputs (resource names, connection strings) feed into subsequent stages.

Setting Output Variables

Use ##vso[task.setvariable] in PowerShell or Bash steps to export dynamic values as pipeline variables:

- task: PowerShell@2
  name: bicep_outputs
  displayName: Export deployment outputs
  inputs:
    targetType: inline
    script: |
      ($env:DEPLOYMENT_OUTPUT | ConvertFrom-Json).PSObject.Properties | ForEach-Object {
          Write-Output "##vso[task.setvariable variable=$($_.Name);isOutput=true]$($_.Value.value)"
      }

Mark variables with isOutput=true to make them accessible from other jobs and stages.

Reading Cross-Stage Outputs

Use stageDependencies to reference outputs from prior stages. The syntax depends on whether the source is a regular job or a deployment job:

variables:
  # From a deployment job in a prior stage
  - name: resourceGroupName
    value: $[ stageDependencies.DeployInfra.deploy.outputs['deploy.bicep_outputs.resourceGroupName'] ]

  # From a regular job in a prior stage
  - name: buildVersion
    value: $[ stageDependencies.Build.build.outputs['version.buildVersion'] ]

For outputs between jobs within the same stage, use dependencies instead of stageDependencies:

variables:
  - name: keyVaultName
    value: $[ dependencies.setup.outputs['setup.step_name.keyVaultName'] ]

Multi-Subscription Deployment Pattern

For enterprise environments spanning multiple Azure subscriptions, use per-environment service connections and pass subscription-specific parameters through templates:

# variables.yml
variables:
  devServiceConnection: 'Platform - DEV - Service Connection'
  prodServiceConnection: 'Platform - PROD - Service Connection'

# azure-pipelines.yml
stages:
  - stage: deploy_dev
    jobs:
      - template: templates/environment.yml
        parameters:
          environment: DEV
          serviceConnection: ${{ variables.devServiceConnection }}
          subscriptionId: ${{ variables.devSubscriptionId }}

  - stage: deploy_prod
    dependsOn: deploy_dev
    jobs:
      - template: templates/environment.yml
        parameters:
          environment: PROD
          serviceConnection: ${{ variables.prodServiceConnection }}
          subscriptionId: ${{ variables.prodSubscriptionId }}

IaC Deployment Patterns

Bicep Deployment with AzureResourceManagerTemplateDeployment

For deploying Bicep templates at subscription scope with parameter files:

- task: AzureResourceManagerTemplateDeployment@3
  displayName: Deploy bicep template
  inputs:
    deploymentName: 'environment-${{ lower(parameters.environment) }}-$(Build.BuildNumber)'
    deploymentScope: Subscription
    deploymentOutputs: DEPLOYMENT_OUTPUT
    azureResourceManagerConnection: ${{ parameters.serviceConnection }}
    subscriptionId: ${{ parameters.subscriptionId }}
    location: ${{ parameters.location }}
    csmFile: $(Pipeline.Workspace)/drop/deploy/bicep/main.bicep
    csmParametersFile: $(Pipeline.Workspace)/drop/deploy/bicep/main.${{ lower(parameters.environment) }}.bicepparam
    overrideParameters: '-location "${{ parameters.location }}" -environment "${{ parameters.environment }}"'

Capture outputs with deploymentOutputs and export them with ##vso[task.setvariable] for downstream stages.

Bicep Module Publishing to ACR

Automate publishing of versioned Bicep modules to Azure Container Registry in a dedicated pipeline stage:

- stage: publish_modules
  displayName: Publish IaC bicep modules
  jobs:
    - deployment: deploy
      strategy:
        runOnce:
          deploy:
            steps:
              - task: AzurePowerShell@5
                displayName: Push bicep modules to container registry
                inputs:
                  azureSubscription: ${{ parameters.serviceConnection }}
                  azurePowerShellVersion: latestVersion
                  scriptType: InlineScript
                  inline: |
                    Get-ChildItem -Path "$(modulePath)" -Filter "*.bicep" -Recurse | ForEach-Object {
                        $module = # extract module name and version from filename
                        Publish-AzBicepModule -FilePath $_.FullName -Target "br:$registry/bicep/modules/$module"
                    }

Performance Optimization

• Run independent jobs in parallel by not specifying dependsOn
• Use matrix strategies to test across multiple configurations concurrently
• Cache dependencies and build outputs with Cache@2
• Use shallow clone (fetchDepth: 1) when full git history is not needed
• Use Docker layer caching for container builds
• Configure pipeline resource triggers to chain pipelines efficiently rather than polling

For detailed optimization patterns, see references/optimization.md.

Branch and Trigger Strategy

• Use trigger: for CI on push events; filter by branch and path
• Use pr: for pull request validation; include appropriate branch and path filters
• Use schedules: for maintenance tasks (nightly builds, dependency updates)
• Use resources: pipelines: triggers to chain pipelines (e.g., build completion triggers deployment)
• Disable CI triggers on template-only or documentation-only branches with trigger: none

Example: Multi-Stage Pipeline Structure

trigger:
  branches:
    include:
      - main
      - release/*
  paths:
    exclude:
      - docs/*
      - '*.md'

pr:
  branches:
    include:
      - main

parameters:
  - name: deployEnvironment
    displayName: 'Deploy to environment'
    type: string
    default: 'dev'
    values:
      - dev
      - staging
      - production

variables:
  - group: common-settings
  - name: buildConfiguration
    value: 'Release'

stages:
  - stage: Build
    displayName: 'Build and Test'
    jobs:
      - job: BuildJob
        displayName: 'Build Application'
        pool:
          vmImage: 'ubuntu-22.04'
        steps:
          - checkout: self
            fetchDepth: 1

          - task: Cache@2
            displayName: 'Cache NuGet packages'
            inputs:
              key: 'nuget | "$(Agent.OS)" | **/packages.lock.json'
              restoreKeys: |
                nuget | "$(Agent.OS)"
              path: $(Pipeline.Workspace)/.nuget/packages

          - task: DotNetCoreCLI@2
            displayName: 'Restore dependencies'
            inputs:
              command: restore

          - task: DotNetCoreCLI@2
            displayName: 'Build'
            inputs:
              command: build
              arguments: '--configuration $(buildConfiguration) --no-restore'

          - task: DotNetCoreCLI@2
            displayName: 'Run unit tests'
            inputs:
              command: test
              arguments: '--configuration $(buildConfiguration) --no-build --collect:"XPlat Code Coverage"'
              publishTestResults: true

          - task: PublishCodeCoverageResults@2
            displayName: 'Publish code coverage'
            inputs:
              summaryFileLocation: '$(Agent.TempDirectory)/**/coverage.cobertura.xml'

          - task: PublishPipelineArtifact@1
            displayName: 'Publish build artifact'
            inputs:
              targetPath: '$(Build.ArtifactStagingDirectory)'
              artifactName: 'drop'

  - stage: DeployDev
    displayName: 'Deploy to Dev'
    dependsOn: Build
    condition: and(succeeded(), eq('${{ parameters.deployEnvironment }}', 'dev'))
    jobs:
      - deployment: DeployDev
        displayName: 'Deploy to Dev Environment'
        environment: 'dev'
        strategy:
          runOnce:
            deploy:
              steps:
                - task: AzureKeyVault@2
                  displayName: 'Fetch secrets from Key Vault'
                  inputs:
                    azureSubscription: 'dev-service-connection'
                    KeyVaultName: 'kv-myapp-dev'
                    SecretsFilter: '*'

                - task: AzureWebApp@1
                  displayName: 'Deploy to Azure Web App'
                  inputs:
                    azureSubscription: 'dev-service-connection'
                    appName: 'webapp-myapp-dev'
                    package: '$(Pipeline.Workspace)/drop/**/*.zip'

  - stage: DeployProd
    displayName: 'Deploy to Production'
    dependsOn: DeployDev
    condition: and(succeeded(), eq('${{ parameters.deployEnvironment }}', 'production'))
    jobs:
      - deployment: DeployProd
        displayName: 'Deploy to Production'
        environment: 'production'
        strategy:
          runOnce:
            deploy:
              steps:
                - task: AzureKeyVault@2
                  displayName: 'Fetch secrets from Key Vault'
                  inputs:
                    azureSubscription: 'prod-service-connection'
                    KeyVaultName: 'kv-myapp-prod'
                    SecretsFilter: '*'

                - task: AzureWebApp@1
                  displayName: 'Deploy to Azure Web App'
                  inputs:
                    azureSubscription: 'prod-service-connection'
                    appName: 'webapp-myapp-prod'
                    package: '$(Pipeline.Workspace)/drop/**/*.zip'

Anti-Patterns to Avoid

Anti-Pattern	Why It Is Harmful	Better Approach
Hardcoded secrets in YAML	Secrets visible in source control; security breach risk	Use variable groups linked to Azure Key Vault
Single monolithic pipeline file	Difficult to maintain, test, and reuse across projects	Break into templates for stages, jobs, and steps
Using latest VM images	Builds break unpredictably when the image updates	Pin to a specific image version (e.g., ubuntu-22.04)
No dependsOn or condition	Stages run unconditionally, wasting time and resources	Use dependsOn for ordering and condition for gating
Ignoring test failures (continueOnError: true)	Broken code proceeds to deployment; bugs reach production	Set failTaskOnFailedTests: true; fail the build on test failures
Duplicated steps across pipelines	Maintenance burden; drift between pipeline copies	Extract into step or job templates; share via a templates repo
Overly broad service connection permissions	Violates least privilege; larger blast radius if compromised	Scope service connections to specific resource groups and roles
No caching of dependencies	Every build re-downloads packages; slow feedback loops	Use Cache@2 with hashFiles-based keys
Skipping approval gates for production	Accidental or unauthorized production deployments	Configure environment approvals and branch control checks
Deep git clones when not needed	Wastes time and bandwidth fetching full history	Use fetchDepth: 1 for shallow clones when history is irrelevant
Polling for pipeline chaining	Wasteful and slow; adds unnecessary delay	Use resources: pipelines: triggers for event-driven chaining
No timeout on jobs	Stuck jobs consume agent capacity indefinitely	Set timeoutInMinutes on every job

Pipeline Review Checklist

Use this checklist when creating or reviewing Azure DevOps Pipeline YAML files.

General Structure

• Pipeline has a clear name or the file is descriptively named
• Appropriate trigger and pr settings with branch and path filters
• Stages represent logical phases with meaningful displayName
• dependsOn correctly expresses ordering between stages and jobs
• condition is used for conditional execution where appropriate

Build

• Agent pool uses a pinned VM image version
• Dependencies are cached with Cache@2
• Build artifacts are published with retention policies
• Code quality gates (linting, analysis) are included

Testing

• Unit tests run and results are published (PublishTestResults@2)
• Code coverage is collected and published
• failTaskOnFailedTests: true is set
• Integration/E2E tests run in appropriate stages

Security

• Secrets come from Key Vault or secret-marked variable groups, not inline
• Service connections follow least privilege
• Security scans (dependency, static analysis) are integrated
• Production environments have approval gates and branch control

Deployment

• Deployment jobs use environment: for tracking and approvals
• Strategy (runOnce, rolling, canary) is chosen appropriately
• Health checks and smoke tests run post-deployment
• Rollback plan exists and is tested

Performance

• Independent jobs run in parallel
• Matrix strategies are used for multi-configuration testing
• Shallow clone (fetchDepth: 1) is used where full history is not needed
• timeoutInMinutes is set on all jobs

Templates and Reuse

• Common patterns are extracted into templates
• Shared templates are versioned and consumed via resources: repositories
• Variable templates are used for shared configuration