diff --git a/tests/Aspire.Hosting.Tests/Eventing/DistributedApplicationBuilderEventingTests.cs b/tests/Aspire.Hosting.Tests/Eventing/DistributedApplicationBuilderEventingTests.cs
index 9e0fc14fa3e..11b9c6fe975 100644
--- a/tests/Aspire.Hosting.Tests/Eventing/DistributedApplicationBuilderEventingTests.cs
+++ b/tests/Aspire.Hosting.Tests/Eventing/DistributedApplicationBuilderEventingTests.cs
@@ -23,13 +23,13 @@ public async Task EventsCanBePublishedBlockSequential()
         builder.Eventing.Subscribe<DummyEvent>(async (@event, ct) =>
         {
             blockAssertionTcs.SetResult();
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             await blockFirstSubscriptionTcs.Task;
         });
 
         builder.Eventing.Subscribe<DummyEvent>((@event, ct) =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             return Task.CompletedTask;
         });
 
@@ -54,14 +54,14 @@ public async Task EventsCanBePublishedBlockConcurrent()
 
         builder.Eventing.Subscribe<DummyEvent>(async (@event, ct) =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssertionSub1.SetResult();
             await blockSubscriptionCompletion.Task;
         });
 
         builder.Eventing.Subscribe<DummyEvent>(async (@event, ct) =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssertionSub2.SetResult();
             await blockSubscriptionCompletion.Task;
         });
@@ -87,14 +87,14 @@ public async Task EventsCanBePublishedNonBlockingConcurrent()
         builder.Eventing.Subscribe<DummyEvent>(async (@event, ct) =>
         {
             await blockSubscriptionExecution.Task;
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssertionSub1.SetResult();
         });
 
         builder.Eventing.Subscribe<DummyEvent>(async (@event, ct) =>
         {
             await blockSubscriptionExecution.Task;
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssertionSub2.SetResult();
         });
 
@@ -122,14 +122,14 @@ public async Task EventsCanBePublishedNonBlockingSequential()
         {
             blockAssert1.SetResult();
             await blockEventSub1.Task;
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssert2.SetResult();
             await blockEventSub2.Task;
         });
 
         builder.Eventing.Subscribe<DummyEvent>((@event, ct) =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             blockAssert3.SetResult();
             return Task.CompletedTask;
         });
diff --git a/tests/Aspire.Hosting.Tests/Health/ResourceHealthCheckServiceTests.cs b/tests/Aspire.Hosting.Tests/Health/ResourceHealthCheckServiceTests.cs
index 334a2134dd0..7bc37e09e4a 100644
--- a/tests/Aspire.Hosting.Tests/Health/ResourceHealthCheckServiceTests.cs
+++ b/tests/Aspire.Hosting.Tests/Health/ResourceHealthCheckServiceTests.cs
@@ -209,7 +209,7 @@ public async Task PoorlyImplementedHealthChecksDontCauseMonitoringLoopToCrashout
         var hitCount = 0;
         builder.Services.AddHealthChecks().AddCheck("resource_check", (check) =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             throw new InvalidOperationException("Random failure instead of result!");
         });
 
@@ -250,7 +250,7 @@ public async Task ResourceHealthCheckServiceDoesNotRunHealthChecksUnlessResource
         var checkStatus = HealthCheckResult.Unhealthy();
         builder.Services.AddHealthChecks().AddCheck("parent_test", () =>
         {
-            hitCount++;
+            Interlocked.Increment(ref hitCount);
             return checkStatus;
         });
 
@@ -314,7 +314,7 @@ public async Task ResourceHealthCheckServiceOnlyRaisesResourceReadyOnce()
         var healthCheckHits = 0;
         builder.Services.AddHealthChecks().AddCheck("parent_test", () =>
         {
-            healthCheckHits++;
+            Interlocked.Increment(ref healthCheckHits);
             return HealthCheckResult.Healthy();
         });
 
@@ -327,7 +327,7 @@ public async Task ResourceHealthCheckServiceOnlyRaisesResourceReadyOnce()
         var resourceReadyEventFired = new TaskCompletionSource<ResourceReadyEvent>();
         builder.Eventing.Subscribe<ResourceReadyEvent>(parent.Resource, (@event, ct) =>
         {
-            eventHits++;
+            Interlocked.Increment(ref eventHits);
             return Task.CompletedTask;
         });