diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index c8ff6c8..c125bce 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -79,6 +79,8 @@ jobs:
       vmImage: 'macOS-latest'
 
     steps:
+    - script: brew install mono-libgdiplus
+      displayName: 'Install mono-libgdiplus'
     - powershell: 'Install-Module -Name Pester -Force'
       displayName: 'Update Pester'
     - powershell: './__tests__/CI.ps1 -Test'