diff --git a/devops/build-samples.yml b/devops/build-samples.yml
index 97b9380e206c..d3bb39c70359 100644
--- a/devops/build-samples.yml
+++ b/devops/build-samples.yml
@@ -6,8 +6,28 @@ trigger:
 
 jobs:
 - job: macOS
-  displayName: xamarin macios
+  displayName: Build samples
   timeoutInMinutes: 360
+  strategy:
+    matrix:
+      Debug|iPhone:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^iPhone$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Debug.*$'
+      Debug|iPhoneSimulator:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^iPhoneSimulator$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Debug.*$'
+      Release|iPhone:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^iPhone$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Release.*$'
+      Release|iPhoneSimulator:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^iPhoneSimulator$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Release.*$'
+      Debug|Mac:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Debug.*$'
+      Release|Mac:
+        TEST_PLATFORM_FILTER_EXPRESSION: '^$'
+        TEST_CONFIG_FILTER_EXPRESSION: '^.*Release.*$'
 
   pool:
     vmImage: 'macOS-10.13'
@@ -43,3 +63,4 @@ jobs:
       testResultsFiles: '**/TestResult*.xml'
       testRunTitle: Sample tests (build)
       publishRunAttachments: true
+      mergeTestResults: true
diff --git a/tests/sampletester/SampleTester.cs b/tests/sampletester/SampleTester.cs
index 5259f6bd107c..7feff2603541 100644
--- a/tests/sampletester/SampleTester.cs
+++ b/tests/sampletester/SampleTester.cs
@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.IO;
+using System.Text.RegularExpressions;
 
 using NUnit.Framework;
 
@@ -186,12 +187,29 @@ protected static IEnumerable<SampleTestData> GetSampleTestData (Dictionary<strin
 				}
 			}
 
+			var platform_filter = Environment.GetEnvironmentVariable ("TEST_PLATFORM_FILTER_EXPRESSION");
+			var config_filter = Environment.GetEnvironmentVariable ("TEST_CONFIG_FILTER_EXPRESSION");
+
+			IEnumerable<string> filter (string name, string proj, IEnumerable<string> input, string filter_expression)
+			{
+				if (string.IsNullOrEmpty (filter_expression))
+					return input;
+
+				var filtered = input.Where ((v) => Regex.IsMatch (v, filter_expression));
+				var removed = input.Where ((v) => !filtered.Contains (v));
+				if (removed.Any ()) {
+					Console.WriteLine ($"Filtered out {removed.Count ()} {name}s for {repo}/{proj}: {string.Join (", ", removed)}");
+					return filtered;
+				}
+				return input;
+			}
+
 			// Create the test variations for each project.
 			foreach (var proj in executable_projects) {
 				if (!samples.TryGetValue (proj.RelativePath, out var sample))
 					samples [proj.RelativePath] = sample = new SampleTest ();
 				sample.Project = proj;
-				string [] platforms;
+				IEnumerable<string> platforms;
 				switch (proj.Platform) {
 				case TestPlatform.iOS:
 				case TestPlatform.tvOS:
@@ -204,12 +222,14 @@ protected static IEnumerable<SampleTestData> GetSampleTestData (Dictionary<strin
 				default:
 					throw new NotImplementedException (proj.Platform.ToString ());
 				}
-				foreach (var platform in platforms) {
+
+				foreach (var platform in filter ("platform", proj.Title, platforms, platform_filter)) {
 					var configs = new List<string> ();
 					configs.AddRange (sample.DebugConfigurations ?? defaultDebugConfigurations);
 					configs.AddRange (sample.ReleaseConfigurations ?? defaultReleaseConfigurations);
-					foreach (var config in configs)
+					foreach (var config in filter ("config", proj.Title, configs, config_filter)) {
 						yield return new SampleTestData { SampleTest = sample, Configuration = config, Platform = platform };
+					}
 				}
 			}
 		}