diff --git a/Directory.Packages.props b/Directory.Packages.props
index 4aee092..633b2ea 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -20,7 +20,7 @@
     <PackageVersion Include="ModelContextProtocol" Version="1.4.1"/>
     <PackageVersion Include="Roslynator.Analyzers" Version="4.15.0"/>
     <PackageVersion Include="Roslynator.Formatting.Analyzers" Version="4.15.0"/>
-    <PackageVersion Include="SonarAnalyzer.CSharp" Version="10.29.0.143774"/>
+    <PackageVersion Include="SonarAnalyzer.CSharp" Version="10.30.0.144632"/>
     <PackageVersion Include="Spectre.Console" Version="0.57.2"/>
     <PackageVersion Include="Spectre.Console.Cli" Version="0.55.0"/>
     <PackageVersion Include="Spectre.Console.Testing" Version="0.57.2"/>
diff --git a/tests/ProjGraph.Tests.Integration.Mcp/McpTransportTests.cs b/tests/ProjGraph.Tests.Integration.Mcp/McpTransportTests.cs
index f8b5b3b..3d09859 100644
--- a/tests/ProjGraph.Tests.Integration.Mcp/McpTransportTests.cs
+++ b/tests/ProjGraph.Tests.Integration.Mcp/McpTransportTests.cs
@@ -51,7 +51,7 @@ private static string LocateServerExecutable()
             .FirstOrDefault();
 
         serverExe.Should().NotBeNull($"the MCP server apphost must be present under {binRoot}");
-        return serverExe!.FullName;
+        return serverExe.FullName;
     }
 
     private static string JoinText(CallToolResult result)
diff --git a/tests/ProjGraph.Tests.Unit.ClassDiagram/AnalyzeFileUseCaseTests.cs b/tests/ProjGraph.Tests.Unit.ClassDiagram/AnalyzeFileUseCaseTests.cs
index d94a490..612cf73 100644
--- a/tests/ProjGraph.Tests.Unit.ClassDiagram/AnalyzeFileUseCaseTests.cs
+++ b/tests/ProjGraph.Tests.Unit.ClassDiagram/AnalyzeFileUseCaseTests.cs
@@ -144,7 +144,7 @@ public class Widget { }
         await _sut.ExecuteAsync(filePath);
 
         captured.Should().NotBeNull();
-        captured!.StartDirectory.Should().Be("/work/dir");
+        captured.StartDirectory.Should().Be("/work/dir");
     }
 
     private void SetupFileSystem(string filePath, string code)
diff --git a/tests/ProjGraph.Tests.Unit.ClassDiagram/ClassDiagramCoverageTests.cs b/tests/ProjGraph.Tests.Unit.ClassDiagram/ClassDiagramCoverageTests.cs
index ed12832..d4f4113 100644
--- a/tests/ProjGraph.Tests.Unit.ClassDiagram/ClassDiagramCoverageTests.cs
+++ b/tests/ProjGraph.Tests.Unit.ClassDiagram/ClassDiagramCoverageTests.cs
@@ -109,7 +109,7 @@ public async Task ResolveRelatedSymbol_DiscoveredFileAlreadyInCompilation_Should
         await _fileSystem.DidNotReceive().ReadAllTextAsync(Arg.Any<string>(), Arg.Any<CancellationToken>());
         // The reused tree does not actually declare Ghost, so the original symbol is handed back.
         resolved.Should().NotBeNull();
-        resolved!.Name.Should().Be("Ghost");
+        resolved.Name.Should().Be("Ghost");
     }
 
     [Fact]
@@ -130,7 +130,7 @@ public async Task ResolveRelatedSymbol_DiscoveredFileWithoutMatchingDeclaration_
         var resolved = await sut.ResolveRelatedSymbolAsync(ghost, context);
 
         resolved.Should().NotBeNull();
-        resolved!.Name.Should().Be("Ghost");
+        resolved.Name.Should().Be("Ghost");
     }
 
     [Fact]
@@ -149,7 +149,7 @@ public async Task ResolveRelatedSymbol_DiscoveredFileDeclaringTheType_ShouldReso
         var resolved = await sut.ResolveRelatedSymbolAsync(ghost, context);
 
         resolved.Should().NotBeNull();
-        resolved!.Name.Should().Be("Ghost");
+        resolved.Name.Should().Be("Ghost");
         resolved.TypeKind.Should().Be(Microsoft.CodeAnalysis.TypeKind.Class);
     }
 
diff --git a/tests/ProjGraph.Tests.Unit.ClassDiagram/SymbolResolverTests.cs b/tests/ProjGraph.Tests.Unit.ClassDiagram/SymbolResolverTests.cs
index 672afea..b49c79b 100644
--- a/tests/ProjGraph.Tests.Unit.ClassDiagram/SymbolResolverTests.cs
+++ b/tests/ProjGraph.Tests.Unit.ClassDiagram/SymbolResolverTests.cs
@@ -47,7 +47,7 @@ public async Task ResolveRelatedSymbolAsync_SymbolDeclaredInCompilation_ShouldNo
         var resolved = await sut.ResolveRelatedSymbolAsync(baseSymbol, context);
 
         resolved.Should().NotBeNull();
-        resolved!.Name.Should().Be("Base");
+        resolved.Name.Should().Be("Base");
         await _discovery.DidNotReceive().FindTypeDefinitionFileAsync(Arg.Any<string>(), Arg.Any<string>());
     }
 
diff --git a/tests/ProjGraph.Tests.Unit.EntityFramework/EfDiscoveryCoverageTests.cs b/tests/ProjGraph.Tests.Unit.EntityFramework/EfDiscoveryCoverageTests.cs
index d03cd6a..ad087ef 100644
--- a/tests/ProjGraph.Tests.Unit.EntityFramework/EfDiscoveryCoverageTests.cs
+++ b/tests/ProjGraph.Tests.Unit.EntityFramework/EfDiscoveryCoverageTests.cs
@@ -248,7 +248,7 @@ public class Address
 
         var owned = model.Entities.SingleOrDefault(e => e.Key == "Customer.Addresses");
         owned.Should().NotBeNull("OwnsMany over an array navigation must still capture the owned type");
-        owned!.IsCollection.Should().BeTrue();
+        owned.IsCollection.Should().BeTrue();
         owned.Properties.Select(p => p.Name).Should().Contain("Street").And.Contain("City");
     }
 
diff --git a/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedCrossFileTypeRegressionTests.cs b/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedCrossFileTypeRegressionTests.cs
index 5e70aad..0988668 100644
--- a/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedCrossFileTypeRegressionTests.cs
+++ b/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedCrossFileTypeRegressionTests.cs
@@ -83,7 +83,7 @@ public record Money(decimal Amount, string Currency = "USD");
         var owned = model.Entities.SingleOrDefault(e => e.Key == "Product.Price");
         owned.Should().NotBeNull(
             "OwnsOne(p => p.Price) must capture the owned entity even though Money.cs is a separate file");
-        owned!.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
+        owned.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
             "Money's columns can only come from CLR seeding — there is no Property() call for either — " +
             "so this fails unless Money.cs was pulled into the compilation and resolved");
 
diff --git a/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedRecordOwnerRegressionTests.cs b/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedRecordOwnerRegressionTests.cs
index f0f9ee3..0e6b67a 100644
--- a/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedRecordOwnerRegressionTests.cs
+++ b/tests/ProjGraph.Tests.Unit.EntityFramework/OwnedRecordOwnerRegressionTests.cs
@@ -87,7 +87,7 @@ public class Money
         owned.Should().NotBeNull(
             "OwnsOne(p => p.Price) must capture the owned entity even though Product is record-declared " +
             "and Money.cs is a separate file");
-        owned!.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
+        owned.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
             "the pre-pass must find Price on the record-declared Product to discover Money.cs and pull it " +
             "into the compilation; without that, Money resolves to an error type and the entity is captured " +
             "with zero properties");
@@ -140,7 +140,7 @@ public record Money(decimal Amount, string Currency);
         owned.Should().NotBeNull(
             "OwnsOne(p => p.Price) must capture the owned entity even though Price is declared as a " +
             "primary-constructor parameter rather than a property member");
-        owned!.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
+        owned.Properties.Select(p => p.Name).Should().BeEquivalentTo(["Amount", "Currency"],
             "the pre-pass must find the Price parameter on the positional record to discover Money.cs; " +
             "without that, Money resolves to an error type and the owned entity renders as an empty box");