If you correctly followed the instruction for setting up SmartAssembly on Azure Pipeline, connecting to a database and setting up a error reporting, you should end up with a YAML file similar to the following:

# .NET Desktop
# Build and run tests for .NET Desktop or Windows classic desktop solutions.
# Add steps that publish symbols, save build artifacts, and more:
# https://docs.microsoft.com/azure/devops/pipelines/apps/windows/dot-net

trigger:
- master

pool:
  vmImage: 'windows-latest'

variables:
  solution: '**/*.sln'
  buildPlatform: 'Any CPU'
  buildConfiguration: 'Release'

steps:
- task: NuGetToolInstaller@1

- task: NuGetCommand@2
  inputs:
    restoreSolution: '$(solution)'

### SmartAssembly start ###
- task: NuGetCommand@2
  displayName: 'SmartAssembly download'
  inputs:
    command: 'custom'
    arguments: 'install RedGate.SmartAssembly.Installer /OutputDirectory $(System.DefaultWorkingDirectory)'
 
- task: PowerShell@2
  displayName: 'SmartAssembly installation'
  inputs:
    targetType: 'inline'
    script: |
      $saExtractPath = "$(System.DefaultWorkingDirectory)\RedGate.SmartAssembly.Installer*\tools\"
      $saInstallLocation = "$(System.DefaultWorkingDirectory)\tools\SA\"
      
      "##[debug] Installing SmartAssembly..."
      $msiPath = (Get-ChildItem "$saExtractPath\SmartAssembly_*_x64.msi").FullName
      
      "Installing SmartAssembly from $msiPath into $saInstallLocation"
      $p = Start-Process -FilePath msiexec -Args "/qn /i `"$msiPath`" INSTALLDIR=`"$saInstallLocation`" RG_LICENSE=`"$(SA_KEY)`" RG_WARNING=`"Ignore`" REBOOT=`"ReallySuppress`" RG_I=`"Red Gate Software Ltd.`"" -Wait -Verbose -PassThru
      if ($p.ExitCode -ne 0) {
        throw "SmartAssembly installation failed. Installer exited with code: $($p.ExitCode)"
      }

- task: PowerShell@2
  displayName: 'SmartAssembly.settings'
  inputs:
    targetType: 'inline'
    script: |
      ########################
      $saDbHost = "YOUR_DATABASE_HOST"; # replace with host of your database server
      $saDbUser = "YOUR_DATABASE_USER"; # replace with your database username
      $saDbName = "SmartAssembly";      # database will be created if it doesn't exist
      ########################
      
      $saDbPass = "$(SA_DB_PASSWORD)";
      "<SmartAssembly.Settings><Options><Database ConnectionString='Server=$saDbHost;Initial Catalog=$saDbName;User ID=$saDbUser;Password=$saDbPass' Server='$saDbHost' /></Options></SmartAssembly.Settings>" | Out-File -FilePath "$($env:ProgramData)\Red Gate\SmartAssembly 7\SmartAssembly.settings" -Verbose

- task: PowerShell@2
  displayName: 'Set Azure File Share credentials'
  inputs:
    targetType: 'inline'
    script: |
      ########################
      $fileShareHost = "YOUR_SHARE_HOST"; # replace with host of your Azure File Share server
      $fileShareUser = "YOUR_SHARE_USER"; # replace with your Azure File Share username
      ########################
      
      $fileSharePass = "$(SA_FS_PASSWORD)";
      Invoke-Expression -Command "cmdkey /add:$fileShareHost /user:$fileShareUser /pass:$fileSharePass"
### SmartAssembly end ###

- task: VSBuild@1
  inputs:
    solution: '$(solution)'
    platform: '$(buildPlatform)'
    configuration: '$(buildConfiguration)'

### SmartAssembly start ###
- task: PowerShell@2
  displayName: 'SmartAssembly deactivation'
  condition: always()
  inputs:
    targetType: 'inline'
    script: |
      $saInstallLocation = "$(System.DefaultWorkingDirectory)\Tools\SA\"
      $saComPath = "$saInstallLocation\SmartAssembly.com"
 
      "##[debug] Deactivating SmartAssembly..."
      $p = Start-Process -FilePath $saComPath -Args "/deactivateSerial" -PassThru -NoNewWindow -Wait
      if ($p.ExitCode -ne 0) {
        throw "Unable to deactivate SmartAssembly."
      }
### SmartAssembly end ###

- task: VSTest@2
  inputs:
    platform: '$(buildPlatform)'
    configuration: '$(buildConfiguration)'

Next steps

You can use the "variables" configuration section to store commonly used values (e.g. database and file share hosts and usernames). The variables can be used similarly to already defined solution, buildPlatform and buildConfiguration variables.

You may also want to use one of the available Azure tasks to store the assemblies processed by SmartAssembly as build artifacts, depending on the output location set in your .saproj file.