diff --git a/examples/WireMock.Net.StandAlone.NETCoreApp/Program.cs b/examples/WireMock.Net.StandAlone.NETCoreApp/Program.cs
index 5871bf0a..b3af5d9d 100644
--- a/examples/WireMock.Net.StandAlone.NETCoreApp/Program.cs
+++ b/examples/WireMock.Net.StandAlone.NETCoreApp/Program.cs
@@ -7,15 +7,15 @@ namespace WireMock.Net.StandAlone.NETCoreApp
     class Program
     {
         private static int sleepTime = 30000;
-        private static FluentMockServer server;
+        private static FluentMockServer _server;
 
         static void Main(string[] args)
         {
-            server = StandAloneApp.Start(args);
+            _server = StandAloneApp.Start(args);
 
             Console.WriteLine($"{DateTime.UtcNow} Press Ctrl+C to shut down");
 
-            System.Console.CancelKeyPress += (s,e) =>
+            Console.CancelKeyPress += (s, e) =>
             {
                 Stop("CancelKeyPress");
             };
@@ -25,7 +25,7 @@ namespace WireMock.Net.StandAlone.NETCoreApp
                 Stop("AssemblyLoadContext.Default.Unloading");
             };
 
-            while(true)
+            while (true)
             {
                 Console.WriteLine($"{DateTime.UtcNow} WireMock.Net server running");
                 Thread.Sleep(sleepTime);
@@ -35,7 +35,7 @@ namespace WireMock.Net.StandAlone.NETCoreApp
         private static void Stop(string why)
         {
             Console.WriteLine($"{DateTime.UtcNow} WireMock.Net server stopping because '{why}'");
-            server.Stop();
+            _server.Stop();
             Console.WriteLine($"{DateTime.UtcNow} WireMock.Net server stopped");
         }
     }
diff --git a/src/WireMock.Net/Http/PortUtil.cs b/src/WireMock.Net/Http/PortUtil.cs
index 0f101c75..4ebba7df 100644
--- a/src/WireMock.Net/Http/PortUtil.cs
+++ b/src/WireMock.Net/Http/PortUtil.cs
@@ -5,18 +5,15 @@ using System.Text.RegularExpressions;
 namespace WireMock.Http
 {
     /// <summary>
-    /// Utility class
+    /// Port Utility class
     /// </summary>
     public static class PortUtil
     {
         private static readonly Regex UrlDetailsRegex = new Regex(@"^(?<proto>\w+)://[^/]+?(?<port>\d+)?/", RegexOptions.Compiled);
 
         /// <summary>
-        /// The find free TCP port.
+        /// Finds a free TCP port.
         /// </summary>
-        /// <returns>
-        /// The <see cref="int"/>.
-        /// </returns>
         /// <remarks>see http://stackoverflow.com/questions/138043/find-the-next-tcp-port-in-net.</remarks>
         public static int FindFreeTcpPort()
         {
diff --git a/src/WireMock.Net/Server/FluentMockServer.Admin.cs b/src/WireMock.Net/Server/FluentMockServer.Admin.cs
index 21072672..e09747a6 100644
--- a/src/WireMock.Net/Server/FluentMockServer.Admin.cs
+++ b/src/WireMock.Net/Server/FluentMockServer.Admin.cs
@@ -29,6 +29,7 @@ namespace WireMock.Server
     public partial class FluentMockServer
     {
         private static readonly string AdminMappingsFolder = Path.Combine("__admin", "mappings");
+        private const string ContentTypeJson = "application/json";
         private const string AdminMappings = "/__admin/mappings";
         private const string AdminRequests = "/__admin/requests";
         private const string AdminSettings = "/__admin/settings";
@@ -86,12 +87,12 @@ namespace WireMock.Server
         {
             // __admin/settings
             Given(Request.Create().WithPath(AdminSettings).UsingGet()).RespondWith(new DynamicResponseProvider(SettingsGet));
-            Given(Request.Create().WithPath(AdminSettings).UsingVerb("PUT", "POST").WithHeader("Content-Type", "application/json")).RespondWith(new DynamicResponseProvider(SettingsUpdate));
+            Given(Request.Create().WithPath(AdminSettings).UsingVerb("PUT", "POST").WithHeader(HttpKnownHeaderNames.ContentType, ContentTypeJson)).RespondWith(new DynamicResponseProvider(SettingsUpdate));
 
 
             // __admin/mappings
             Given(Request.Create().WithPath(AdminMappings).UsingGet()).RespondWith(new DynamicResponseProvider(MappingsGet));
-            Given(Request.Create().WithPath(AdminMappings).UsingPost().WithHeader("Content-Type", "application/json")).RespondWith(new DynamicResponseProvider(MappingsPost));
+            Given(Request.Create().WithPath(AdminMappings).UsingPost().WithHeader(HttpKnownHeaderNames.ContentType, ContentTypeJson)).RespondWith(new DynamicResponseProvider(MappingsPost));
             Given(Request.Create().WithPath(AdminMappings).UsingDelete()).RespondWith(new DynamicResponseProvider(MappingsDelete));
 
             // __admin/mappings/reset
@@ -99,7 +100,7 @@ namespace WireMock.Server
 
             // __admin/mappings/{guid}
             Given(Request.Create().WithPath(_adminMappingsGuidPathMatcher).UsingGet()).RespondWith(new DynamicResponseProvider(MappingGet));
-            Given(Request.Create().WithPath(_adminMappingsGuidPathMatcher).UsingPut().WithHeader("Content-Type", "application/json")).RespondWith(new DynamicResponseProvider(MappingPut));
+            Given(Request.Create().WithPath(_adminMappingsGuidPathMatcher).UsingPut().WithHeader(HttpKnownHeaderNames.ContentType, ContentTypeJson)).RespondWith(new DynamicResponseProvider(MappingPut));
             Given(Request.Create().WithPath(_adminMappingsGuidPathMatcher).UsingDelete()).RespondWith(new DynamicResponseProvider(MappingDelete));
 
             // __admin/mappings/save