2.4.0

* Bump OpenTelemetry.Exporter.OpenTelemetryProtocol from 1.14.0 to 1.15.3

---
updated-dependencies:
- dependency-name: OpenTelemetry.Exporter.OpenTelemetryProtocol
  dependency-version: 1.15.3
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

* Upgrade all OpenTelemetry related NuGet packages to latest versions

Agent-Logs-Url: https://github.com/wiremock/WireMock.Net/sessions/5b2f4449-ec3f-49f1-afbe-654e19a97a33

Co-authored-by: StefH <249938+StefH@users.noreply.github.com>

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: StefH <249938+StefH@users.noreply.github.com>

.github/copilot-instructions.md

@@ -1,4 +0,0 @@
-# Copilot Instructions
-
-## Project Guidelines
-- All new byte[xx] calls should use using var data = ArrayPool<byte>.Shared.Lease(xx); instead of directly allocating byte arrays

.github/instructions/instructions.md

@@ -0,0 +1,15 @@
+---
+description: 'Guidelines for this solution'
+applyTo: '**/*.csproj, **/*.cs'
+---
+
+# Multi .NET Framework Targeting
+
+## Instructions
+- The main project "WireMock.Net.Minimal" targets `netstandard2.0` and `net8.0`. Ensure that any new code or dependencies are compatible with these frameworks.
+
+
+# C# Guidelines
+
+## Instructions
+- When a new ByteArray is needed, do not use `var data = new byte[bufferSize];`. Always use `var data = ArrayPool<byte>.Shared.Lease(bufferSize);`.

CHANGELOG.md

@@ -1,3 +1,29 @@
+# 2.4.0 (24 April 2026)
+- [#1437](https://github.com/wiremock/WireMock.Net/pull/1437) - Added feature to enable and disable mappings [feature] contributed by [jayaraman-venkatesan](https://github.com/jayaraman-venkatesan)
+- [#1450](https://github.com/wiremock/WireMock.Net/pull/1450) - Bump OpenTelemetry.Exporter.OpenTelemetryProtocol from 1.14.0 to 1.15.x [dependencies, .NET] contributed by [dependabot[bot]](https://github.com/apps/dependabot)
+- [#1421](https://github.com/wiremock/WireMock.Net/issues/1421) - Deactivate mapping without deleting it [feature]
+
+# 2.3.0 (20 April 2026)
+- [#1436](https://github.com/wiremock/WireMock.Net/pull/1436) - Moving Scenario state change before global response delay is set [feature] contributed by [jayaraman-venkatesan](https://github.com/jayaraman-venkatesan)
+- [#1440](https://github.com/wiremock/WireMock.Net/pull/1440) - Bump log4net from 2.0.15 to 3.3.0 [dependencies] contributed by [dependabot[bot]](https://github.com/apps/dependabot)
+- [#1443](https://github.com/wiremock/WireMock.Net/pull/1443) - Fix ExactMatcher and JsonMatcher not working for ISO dates as string [bug] contributed by [StefH](https://github.com/StefH)
+- [#1444](https://github.com/wiremock/WireMock.Net/pull/1444) - Update instructions.md [refactor] contributed by [StefH](https://github.com/StefH)
+- [#1448](https://github.com/wiremock/WireMock.Net/pull/1448) - Use DefaultJsonSerializer for BodyAsJson-Response [bug] contributed by [StefH](https://github.com/StefH)
+- [#1205](https://github.com/wiremock/WireMock.Net/issues/1205) - System.Private.Uri 4.3.0 Blackduck security High vulnerability [bug]
+- [#1260](https://github.com/wiremock/WireMock.Net/issues/1260) - Scenario state change before a response delay timeout ends [bug]
+- [#1441](https://github.com/wiremock/WireMock.Net/issues/1441) - ExactMatcher and JsonMatcher not working for ISO dates in v2.2.0 [bug]
+- [#1446](https://github.com/wiremock/WireMock.Net/issues/1446) - WithBodyAsJson does not return correctly formatted json when using SystemTextJsonConverter [bug]
+
+# 2.2.0 (30 March 2026)
+- [#1433](https://github.com/wiremock/WireMock.Net/pull/1433) - Add comments for ScenarioStateStore related code [refactor] contributed by [StefH](https://github.com/StefH)
+- [#1434](https://github.com/wiremock/WireMock.Net/pull/1434) - Upgrade Scriban.Signed [security] contributed by [StefH](https://github.com/StefH)
+
+# 2.1.0 (29 March 2026)
+- [#1425](https://github.com/wiremock/WireMock.Net/pull/1425) - Add helpers for query params fluent MappingModelBuilder [feature] contributed by [biltongza](https://github.com/biltongza)
+- [#1430](https://github.com/wiremock/WireMock.Net/pull/1430) - Add injectable IScenarioStateStore for distributed scenario state [feature] contributed by [m4tchl0ck](https://github.com/m4tchl0ck)
+- [#1431](https://github.com/wiremock/WireMock.Net/pull/1431) - Fix WireMockLogger implementation in dotnet-WireMock [bug] contributed by [StefH](https://github.com/StefH)
+- [#1432](https://github.com/wiremock/WireMock.Net/pull/1432) - Add WireMockAspNetCoreLogger to log Kestrel warnings/errors [feature] contributed by [StefH](https://github.com/StefH)
+
 # 2.0.0 (11 March 2026)
 - [#1359](https://github.com/wiremock/WireMock.Net/pull/1359) - Version 2.x contributed by [StefH](https://github.com/StefH)
 - [#1394](https://github.com/wiremock/WireMock.Net/pull/1394) - MappingSerializer (Newtonsoft or SystemText)-Json [feature] contributed by [StefH](https://github.com/StefH)
@@ -1356,11 +1382,11 @@
 - [#145](https://github.com/wiremock/WireMock.Net/pull/145) - Cancellation token not passed to server instance in .NET Core 2 [bug] contributed by [Bob11327](https://github.com/Bob11327)
 
 # 1.0.3.18 (25 May 2018)
-- [#142](https://github.com/wiremock/WireMock.Net/pull/142) - Allow all headers to be set as Response headers contributed by [StefH](https://github.com/StefH)
+- [#142](https://github.com/wiremock/WireMock.Net/pull/142) - Allow all headers to be set as Response headers [bug] contributed by [StefH](https://github.com/StefH)
 - [#122](https://github.com/wiremock/WireMock.Net/issues/122) - WireMock.Net not responding in unit tests - same works in console application
 - [#126](https://github.com/wiremock/WireMock.Net/issues/126) - Question: UsingHead always returns 0 for Content-Length header even when explicitly specified
 - [#132](https://github.com/wiremock/WireMock.Net/issues/132) - LogEntries not being recorded on subsequent tests
-- [#136](https://github.com/wiremock/WireMock.Net/issues/136) - Question: Does the WireMock send Content-Length response header
+- [#136](https://github.com/wiremock/WireMock.Net/issues/136) - Question: Does the WireMock send Content-Length response header [bug]
 - [#137](https://github.com/wiremock/WireMock.Net/issues/137) - Question: How to specify Transfer-Encoding response header?
 - [#139](https://github.com/wiremock/WireMock.Net/issues/139) - Wiki link https://github.com/StefH/WireMock.Net/wiki/Record-(via-proxy)-and-Save is dead
 

Directory.Build.props

@@ -4,7 +4,7 @@
     </PropertyGroup>
 
     <PropertyGroup>
-        <VersionPrefix>2.0.0</VersionPrefix>
+        <VersionPrefix>2.4.0</VersionPrefix>
         <PackageIcon>WireMock.Net-Logo.png</PackageIcon>
         <PackageProjectUrl>https://github.com/wiremock/WireMock.Net</PackageProjectUrl>
         <PackageLicenseExpression>Apache-2.0</PackageLicenseExpression>

Generate-ReleaseNotes.cmd

@@ -1,7 +1,7 @@
 rem https://github.com/StefH/GitHubReleaseNotes
 
-SET version=2.0.0
+SET version=2.4.0
 
 GitHubReleaseNotes --output CHANGELOG.md --skip-empty-releases --exclude-labels wontfix test question invalid doc duplicate example environment --version %version% --token %GH_TOKEN%
 
-GitHubReleaseNotes --output PackageReleaseNotes.txt --skip-empty-releases --exclude-labels test question invalid doc duplicate example environment --template PackageReleaseNotes.template --version %version% --token %GH_TOKEN%
+GitHubReleaseNotes --output PackageReleaseNotes.txt --skip-empty-releases --exclude-labels wontfix test question invalid doc duplicate example environment --template PackageReleaseNotes.template --version %version% --token %GH_TOKEN%

PackageReleaseNotes.txt

@@ -1,8 +1,6 @@
-# 2.0.0 (11 March 2026)
+# 2.4.0 (24 April 2026)
-- #1359 Version 2.x
+- #1437 Added feature to enable and disable mappings [feature]
-- #1394 MappingSerializer (Newtonsoft or SystemText)-Json [feature]
+- #1450 Bump OpenTelemetry.Exporter.OpenTelemetryProtocol from 1.14.0 to 1.15.x [dependencies, .NET]
-- #1341 Configurable JSON serialization support (Newtonsoft.Json vs System.Text.Json) [feature]
+- #1421 Deactivate mapping without deleting it [feature]
-- #1422 WireMock.Net seems to be incompatible with Microsoft.Owin.Security.Interop [bug]
-- #1424 WireMock.Net.FluentAssertions is incompatible with WireMock.Net.Aspire [feature]
 
 The full release notes can be found here: https://github.com/wiremock/WireMock.Net/blob/master/CHANGELOG.md

README.md

@@ -71,6 +71,7 @@ A C# .NET version based on [mock4net](https://github.com/alexvictoor/mock4net) w
 |   **WireMock.Net.OpenTelemetry** | [![NuGet Badge WireMock.Net.OpenTelemetry](https://img.shields.io/nuget/v/WireMock.Net.OpenTelemetry)](https://www.nuget.org/packages/WireMock.Net.ProtoBuf) | [![MyGet Badge WireMock.Net.OpenTelemetry](https://img.shields.io/myget/wiremock-net/vpre/WireMock.Net.OpenTelemetry?includePreReleases=true&label=MyGet)](https://www.myget.org/feed/wiremock-net/package/nuget/WireMock.Net.OpenTelemetry)
 | | | |
 |   **WireMock.Net.RestClient** | [![NuGet Badge WireMock.Net.RestClient](https://img.shields.io/nuget/v/WireMock.Net.RestClient)](https://www.nuget.org/packages/WireMock.Net.RestClient) | [![MyGet Badge WireMock.Net.RestClient](https://img.shields.io/myget/wiremock-net/vpre/WireMock.Net.RestClient?includePreReleases=true&label=MyGet)](https://www.myget.org/feed/wiremock-net/package/nuget/WireMock.Net.RestClient)
+|   **WireMock.Net.RestClient.AwesomeAssertions** | [![NuGet Badge WireMock.Net.RestClient.AwesomeAssertions](https://img.shields.io/nuget/v/WireMock.Net.RestClient.AwesomeAssertions)](https://www.nuget.org/packages/WireMock.Net.RestClient.AwesomeAssertions) | [![MyGet Badge WireMock.Net.RestClient.AwesomeAssertions](https://img.shields.io/myget/wiremock-net/vpre/WireMock.Net.RestClient.AwesomeAssertions?includePreReleases=true&label=MyGet)](https://www.myget.org/feed/wiremock-net/package/nuget/WireMock.Net.RestClient.AwesomeAssertions)
 |   **WireMock.Org.RestClient** | [![NuGet Badge WireMock.Org.RestClient](https://img.shields.io/nuget/v/WireMock.Org.RestClient)](https://www.nuget.org/packages/WireMock.Org.RestClient) | [![MyGet Badge WireMock.Org.RestClient](https://img.shields.io/myget/wiremock-net/vpre/WireMock.Org.RestClient?includePreReleases=true&label=MyGet)](https://www.myget.org/feed/wiremock-net/package/nuget/WireMock.Org.RestClient)
 
 <br />

examples-Aspire/AspireApp1.ServiceDefaults/AspireApp1.ServiceDefaults.csproj

@@ -12,11 +12,11 @@
 
     <PackageReference Include="Microsoft.Extensions.Http.Resilience" Version="8.4.0" />
     <PackageReference Include="Microsoft.Extensions.ServiceDiscovery" Version="8.0.0" />
-    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.8.1" />
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.3" />
-    <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.8.1" />
+    <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.15.3" />
-    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.8.1" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.15.2" />
-    <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.8.1" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.15.1" />
-    <PackageReference Include="OpenTelemetry.Instrumentation.Runtime" Version="1.8.0" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.Runtime" Version="1.15.1" />
   </ItemGroup>
 
 </Project>

examples/WireMock.Net.Client/Program.cs

@@ -82,6 +82,51 @@ class Program
             )
         );
 
+        mappingBuilder.Given(m => m
+            .WithRequest(req => req
+                .WithPath("/testRequestWithQueryParams")
+                .UsingGet()
+                .WithParams(p => p.WithParam("param1", pb => pb.WithExactMatcher("value1")))
+            ).WithResponse(rsp => rsp
+                .WithHeaders(h => h.Add("Content-Type", "application/json"))
+                .WithStatusCode(200)
+                .WithBodyAsJson(new
+                {
+                    status = "ok"
+                }, true)
+            )
+        );
+
+        mappingBuilder.Given(m => m
+            .WithRequest(req => req
+                .WithPath("/testRequestWithHeaders")
+                .UsingGet()
+                .WithHeaders(h => h.WithHeader("Accept", hb => hb.WithExactMatcher("application/json")))
+            ).WithResponse(rsp => rsp
+                .WithHeaders(h => h.Add("Content-Type", "application/json"))
+                .WithStatusCode(200)
+                .WithBodyAsJson(new
+                {
+                    status = "ok"
+                }, true)
+            )
+        );
+
+        mappingBuilder.Given(m => m
+            .WithRequest(req => req
+                .WithPath("/testRequestWithCookie")
+                .UsingGet()
+                .WithCookies(c => c.WithCookie("cookie1", cb => cb.WithExactMatcher("cookievalue1")))
+            ).WithResponse(rsp => rsp
+                .WithHeaders(h => h.Add("Content-Type", "application/json"))
+                .WithStatusCode(200)
+                .WithBodyAsJson(new
+                {
+                    status = "ok"
+                }, true)
+            )
+        );
+
         var result = await mappingBuilder.BuildAndPostAsync().ConfigureAwait(false);
         Console.WriteLine($"result = {JsonConvert.SerializeObject(result)}");
 

examples/WireMock.Net.Console.NET8/MainApp.cs

@@ -8,6 +8,7 @@ using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using Newtonsoft.Json;
+using SharpYaml.Model;
 using WireMock.Logging;
 using WireMock.Matchers;
 using WireMock.Models;
@@ -288,7 +289,24 @@ namespace WireMock.Net.ConsoleApplication
 
             var todos = new Dictionary<int, Todo>();
 
-            var server = WireMockServer.Start();
+            var server = WireMockServer.Start(new WireMockServerSettings
+            {
+                Logger = new WireMockConsoleLogger(),
+
+                Port = 9091
+            });
+
+            server
+               .WhenRequest(r => r
+                   .WithPath("/Content-Length")
+                   .UsingAnyMethod()
+               )
+               .ThenRespondWith(r => r
+                   .WithStatusCode(HttpStatusCode.OK)
+                   .WithHeader("Content-Length", "42")
+               );
+
+            System.Console.ReadLine();
 
             //server
             //    .Given(Request.Create()

examples/WireMock.Net.Console.NET8/WireMock.Net.Console.NET8.csproj

@@ -18,7 +18,7 @@
 
     <ItemGroup>
         <ProjectReference Include="..\..\src\WireMock.Net\WireMock.Net.csproj" />
-        <PackageReference Include="log4net" Version="2.0.15" />
+        <PackageReference Include="log4net" Version="3.3.0" />
         <PackageReference Include="Microsoft.Extensions.Configuration" Version="8.0.0" />
     </ItemGroup>
 

examples/WireMock.Net.OpenTelemetryDemo/WireMock.Net.OpenTelemetryDemo.csproj

@@ -8,9 +8,9 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.15.3" />
-        <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.15.1" />
-        <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.3" />
     </ItemGroup>
 
     <ItemGroup>

examples/WireMock.Net.WebApplication.IIS/App.cs

@@ -1,29 +1,18 @@
 // Copyright © WireMock.Net
 
-using Microsoft.Extensions.Hosting;
-using System.Threading;
-using System.Threading.Tasks;
-
 namespace WireMock.Net.WebApplication;
 
-public class App : IHostedService
+public class App(IWireMockService service) : IHostedService
 {
-    private readonly IWireMockService _service;
-        
-    public App(IWireMockService service)
-    {
-        _service = service;
-    }
-
     public Task StartAsync(CancellationToken cancellationToken)
     {
-        _service.Start();
+        service.Start();
         return Task.CompletedTask;
     }
 
     public Task StopAsync(CancellationToken cancellationToken)
     {
-        _service.Stop();
+        service.Stop();
         return Task.CompletedTask;
     }
 }

examples/WireMock.Net.WebApplication.IIS/Program.cs

@@ -1,9 +1,5 @@
 // Copyright © WireMock.Net
 
-using Microsoft.Extensions.Configuration;
-using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.Hosting;
-using Microsoft.Extensions.Logging;
 using WireMock.Settings;
 
 namespace WireMock.Net.WebApplication;

examples/WireMock.Net.WebApplication.IIS/WireMock.Net.WebApplication.IIS.csproj

@@ -15,7 +15,6 @@
     </ItemGroup>
 
     <ItemGroup>
-        <ProjectReference Include="..\..\src\WireMock.Net.Abstractions\WireMock.Net.Abstractions.csproj" />
         <ProjectReference Include="..\..\src\WireMock.Net\WireMock.Net.csproj" />
     </ItemGroup>
 

examples/WireMock.Net.WebApplication.IIS/WireMockService.cs

@@ -1,7 +1,5 @@
 // Copyright © WireMock.Net
 
-using System;
-using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using Newtonsoft.Json;
 using WireMock.Admin.Requests;

examples/WireMock.Net.WebApplication.IIS/appsettings.json

@@ -15,7 +15,7 @@
     "WireMockServerSettings": {
         "StartAdminInterface": true,
         "Urls": [
-            "http://localhost"
+            "http://localhost:0"
         ]
     }
 }

examples/WireMock.Net.WebApplication.IIS/web.config

@@ -1,12 +1,17 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <configuration>
-  <!--
+    <!--
     Configure your application settings in appsettings.json. Learn more at http://go.microsoft.com/fwlink/?LinkId=786380
-  -->
+    -->
-  <system.webServer>
+    <system.webServer>
-    <handlers>
+        <handlers>
-      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModuleV2" resourceType="Unspecified" />
+            <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModuleV2" resourceType="Unspecified" />
-    </handlers>
+        </handlers>
-    <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false" />
+        <httpProtocol>
-  </system.webServer>
+            <customHeaders>
+                <add name="X-Frame-Options" value="SAMEORIGIN" />
+            </customHeaders>
+        </httpProtocol>
+        <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false" />
+    </system.webServer>
 </configuration>

src/WireMock.Net.Abstractions/Admin/Mappings/MappingModel.cs

@@ -55,12 +55,17 @@ public class MappingModel
     /// In case the value is null state will not be changed.
     /// </summary>
     public string? SetStateTo { get; set; }
-    
+
     /// <summary>
     /// The number of times this match should be matched before the state will be changed to the specified one.
     /// </summary>
     public int? TimesInSameState { get; set; }
 
+    /// <summary>
+    /// Value to determine if the mapping is disabled. Defaults to <c>null</c> (not disabled).
+    /// </summary>
+    public bool? IsDisabled { get; set; }
+
     /// <summary>
     /// The request model.
     /// </summary>
@@ -100,7 +105,7 @@ public class MappingModel
     /// </summary>
     public object? Data { get; set; }
 
-    /// <summary> 
+    /// <summary>
     /// The probability when this request should be matched. Value is between 0 and 1. [Optional]
     /// </summary>
     public double? Probability { get; set; }

src/WireMock.Net.Abstractions/BuilderExtensions/ArrayMatcherModelBuilder.cs

@@ -0,0 +1,39 @@
+// Copyright © WireMock.Net
+
+namespace WireMock.Admin.Mappings;
+
+public partial class ArrayMatcherModelBuilder
+{
+    public ArrayMatcherModelBuilder WithExactMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("ExactMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public ArrayMatcherModelBuilder WithWildcardMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("WildcardMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public ArrayMatcherModelBuilder WithRegexMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("RegexMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public ArrayMatcherModelBuilder WithNotNullOrEmptyMatcher(bool rejectOnMatch = false)
+    {
+        return Add(mb => mb
+            .WithName("NotNullOrEmptyMatcher")
+            .WithRejectOnMatch(rejectOnMatch)
+        );
+    }
+
+    private ArrayMatcherModelBuilder WithMatcher(string name, object pattern, bool rejectOnMatch, bool ignoreCase = false)
+    {
+        return Add(mb => mb
+            .WithName(name)
+            .WithPattern(pattern)
+            .WithRejectOnMatch(rejectOnMatch)
+            .WithIgnoreCase(ignoreCase)
+        );
+    }
+}

src/WireMock.Net.Abstractions/BuilderExtensions/IListCookieModelBuilder.cs

@@ -0,0 +1,19 @@
+// Copyright © WireMock.Net
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace WireMock.Admin.Mappings;
+
+public partial class IListCookieModelBuilder
+{
+    public IListCookieModelBuilder WithCookie(string name, Action<IListMatcherModelBuilder> action, bool rejectOnMatch = false)
+    {
+        return Add(cookieBuilder => cookieBuilder
+            .WithName(name)
+            .WithRejectOnMatch(rejectOnMatch)
+            .WithMatchers(matchersBuilder => action(matchersBuilder))
+        );
+    }
+}

src/WireMock.Net.Abstractions/BuilderExtensions/IListHeaderModelBuilder.cs

@@ -0,0 +1,19 @@
+// Copyright © WireMock.Net
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace WireMock.Admin.Mappings;
+
+public partial class IListHeaderModelBuilder
+{
+    public IListHeaderModelBuilder WithHeader(string name, Action<IListMatcherModelBuilder> action, bool rejectOnMatch = false)
+    {
+        return Add(headerBuilder => headerBuilder
+            .WithName(name)
+            .WithRejectOnMatch(rejectOnMatch)
+            .WithMatchers(matchersBuilder => action(matchersBuilder))
+        );
+    }
+}

src/WireMock.Net.Abstractions/BuilderExtensions/IListMatcherModelBuilder.cs

@@ -0,0 +1,39 @@
+// Copyright © WireMock.Net
+
+namespace WireMock.Admin.Mappings;
+
+public partial class IListMatcherModelBuilder
+{
+    public IListMatcherModelBuilder WithExactMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("ExactMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public IListMatcherModelBuilder WithWildcardMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("WildcardMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public IListMatcherModelBuilder WithRegexMatcher(object pattern, bool rejectOnMatch = false, bool ignoreCase = false)
+    {
+        return WithMatcher("RegexMatcher", pattern, rejectOnMatch, ignoreCase);
+    }
+
+    public IListMatcherModelBuilder WithNotNullOrEmptyMatcher(bool rejectOnMatch = false)
+    {
+        return Add(mb => mb
+            .WithName("NotNullOrEmptyMatcher")
+            .WithRejectOnMatch(rejectOnMatch)
+        );
+    }
+
+    private IListMatcherModelBuilder WithMatcher(string name, object pattern, bool rejectOnMatch, bool ignoreCase = false)
+    {
+        return Add(mb => mb
+            .WithName(name)
+            .WithPattern(pattern)
+            .WithRejectOnMatch(rejectOnMatch)
+            .WithIgnoreCase(ignoreCase)
+        );
+    }
+}

src/WireMock.Net.Abstractions/BuilderExtensions/IListParamModelBuilder.cs

@@ -0,0 +1,17 @@
+// Copyright © WireMock.Net
+
+using System;
+
+namespace WireMock.Admin.Mappings;
+
+public partial class IListParamModelBuilder
+{
+    public IListParamModelBuilder WithParam(string name, Action<ArrayMatcherModelBuilder> action, bool rejectOnMatch = false)
+    {
+        return Add(paramBuilder => paramBuilder
+            .WithName(name)
+            .WithRejectOnMatch(rejectOnMatch)
+            .WithMatchers(matchersBuilder => action(matchersBuilder))
+        );
+    }
+}

src/WireMock.Net.Abstractions/Handlers/IScenarioStateStore.cs

@@ -0,0 +1,24 @@
+// Copyright © WireMock.Net
+
+using System.Diagnostics.CodeAnalysis;
+
+namespace WireMock.Handlers;
+
+public interface IScenarioStateStore
+{
+    bool TryGet(string name, [NotNullWhen(true)] out ScenarioState? state);
+
+    IReadOnlyList<ScenarioState> GetAll();
+
+    bool ContainsKey(string name);
+
+    bool TryAdd(string name, ScenarioState scenarioState);
+
+    ScenarioState AddOrUpdate(string name, Func<string, ScenarioState> addFactory, Func<string, ScenarioState, ScenarioState> updateFactory);
+
+    ScenarioState? Update(string name, Action<ScenarioState> updateAction);
+
+    bool TryRemove(string name);
+
+    void Clear();
+}

src/WireMock.Net.Abstractions/Matchers/Request/MatchDetail.cs

@@ -10,7 +10,7 @@ public class MatchDetail
     /// <summary>
     /// Gets or sets the type of the matcher.
     /// </summary>
-    public required Type MatcherType { get; set; }
+    public required string MatcherType { get; set; }
 
     /// <summary>
     /// Gets or sets the type of the matcher.

src/WireMock.Net.Abstractions/ScenarioState.cs

@@ -31,4 +31,4 @@ public class ScenarioState
     /// Gets or sets the state counter.
     /// </summary>
     public int Counter { get; set; }
-}
+}

src/WireMock.Net.Abstractions/Server/IWireMockServer.cs

@@ -33,12 +33,6 @@ public interface IWireMockServer : IDisposable
     /// </summary>
     IReadOnlyList<MappingModel> MappingModels { get; }
 
-    // <summary>
-    // Gets the mappings.
-    // </summary>
-    //[PublicAPI]
-    //IEnumerable<IMapping> Mappings { get; }
-
     /// <summary>
     /// Gets the ports.
     /// </summary>
@@ -69,8 +63,6 @@ public interface IWireMockServer : IDisposable
     /// </summary>
     string? Provider { get; }
 
-    //ConcurrentDictionary<string, ScenarioState> Scenarios { get; }
-
     /// <summary>
     /// Occurs when [log entries changed].
     /// </summary>
@@ -115,8 +107,6 @@ public interface IWireMockServer : IDisposable
     /// <returns>The <see cref="IReadOnlyList{ILogEntry}"/>.</returns>
     IReadOnlyList<ILogEntry> FindLogEntries(params IRequestMatcher[] matchers);
 
-    // IRespondWithAProvider Given(IRequestMatcher requestMatcher, bool saveToFile = false);
-
     /// <summary>
     /// Reads a static mapping file and adds or updates a single mapping.
     /// 

src/WireMock.Net.Extensions.Routing/WireMock.Net.Extensions.Routing.csproj

@@ -25,7 +25,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-      <PackageReference Include="JsonConverter.Abstractions" Version="0.8.0" />
+      <PackageReference Include="JsonConverter.Abstractions" Version="0.9.0" />
     </ItemGroup>
 
     <ItemGroup>

src/WireMock.Net.Minimal/Handlers/FileBasedScenarioStateStore.cs

@@ -0,0 +1,145 @@
+// Copyright © WireMock.Net
+
+using System.Collections.Concurrent;
+using System.Diagnostics.CodeAnalysis;
+using Newtonsoft.Json;
+using Stef.Validation;
+
+namespace WireMock.Handlers;
+
+/// <summary>
+/// Provides a file-based implementation of <see cref="IScenarioStateStore" /> that persists scenario states to disk and allows concurrent access.
+/// </summary>
+public class FileBasedScenarioStateStore : IScenarioStateStore
+{
+    private readonly ConcurrentDictionary<string, ScenarioState> _scenarios = new(StringComparer.OrdinalIgnoreCase);
+    private readonly string _scenariosFolder;
+    private readonly object _lock = new();
+
+    /// <summary>
+    /// Initializes a new instance of the FileBasedScenarioStateStore class using the specified root folder as the base directory for scenario state storage.
+    /// </summary>
+    /// <param name="rootFolder">The root directory under which scenario state data will be stored. Must be a valid file system path.</param>
+    public FileBasedScenarioStateStore(string rootFolder)
+    {
+        Guard.NotNullOrEmpty(rootFolder);
+
+        _scenariosFolder = Path.Combine(rootFolder, "__admin", "scenarios");
+        Directory.CreateDirectory(_scenariosFolder);
+        LoadScenariosFromDisk();
+    }
+
+    /// <inheritdoc />
+    public bool TryGet(string name, [NotNullWhen(true)] out ScenarioState? state)
+    {
+        return _scenarios.TryGetValue(name, out state);
+    }
+
+    /// <inheritdoc />
+    public IReadOnlyList<ScenarioState> GetAll()
+    {
+        return _scenarios.Values.ToArray();
+    }
+
+    /// <inheritdoc />
+    public bool ContainsKey(string name)
+    {
+        return _scenarios.ContainsKey(name);
+    }
+
+    /// <inheritdoc />
+    public bool TryAdd(string name, ScenarioState scenarioState)
+    {
+        if (_scenarios.TryAdd(name, scenarioState))
+        {
+            WriteScenarioToFile(name, scenarioState);
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <inheritdoc />
+    public ScenarioState AddOrUpdate(string name, Func<string, ScenarioState> addFactory, Func<string, ScenarioState, ScenarioState> updateFactory)
+    {
+        lock (_lock)
+        {
+            var result = _scenarios.AddOrUpdate(name, addFactory, updateFactory);
+            WriteScenarioToFile(name, result);
+            return result;
+        }
+    }
+
+    /// <inheritdoc />
+    public ScenarioState? Update(string name, Action<ScenarioState> updateAction)
+    {
+        lock (_lock)
+        {
+            if (_scenarios.TryGetValue(name, out var state))
+            {
+                updateAction(state);
+                WriteScenarioToFile(name, state);
+                return state;
+            }
+
+            return null;
+        }
+    }
+
+    /// <inheritdoc />
+    public bool TryRemove(string name)
+    {
+        if (_scenarios.TryRemove(name, out _))
+        {
+            DeleteScenarioFile(name);
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <inheritdoc />
+    public void Clear()
+    {
+        _scenarios.Clear();
+
+        foreach (var file in Directory.GetFiles(_scenariosFolder, "*.json"))
+        {
+            File.Delete(file);
+        }
+    }
+
+    private string GetScenarioFilePath(string name)
+    {
+        var sanitized = string.Concat(name.Select(c => Path.GetInvalidFileNameChars().Contains(c) ? '_' : c));
+        return Path.Combine(_scenariosFolder, sanitized + ".json");
+    }
+
+    private void WriteScenarioToFile(string name, ScenarioState state)
+    {
+        var json = JsonConvert.SerializeObject(state, Formatting.Indented);
+        File.WriteAllText(GetScenarioFilePath(name), json);
+    }
+
+    private void DeleteScenarioFile(string name)
+    {
+        var path = GetScenarioFilePath(name);
+        if (File.Exists(path))
+        {
+            File.Delete(path);
+        }
+    }
+
+    private void LoadScenariosFromDisk()
+    {
+        foreach (var file in Directory.GetFiles(_scenariosFolder, "*.json"))
+        {
+            var json = File.ReadAllText(file);
+            var state = JsonConvert.DeserializeObject<ScenarioState>(json);
+            if (state != null)
+            {
+                _scenarios.TryAdd(state.Name, state);
+            }
+        }
+    }
+}

src/WireMock.Net.Minimal/Logging/WireMockAspNetCoreLogger.cs

@@ -0,0 +1,38 @@
+// Copyright © WireMock.Net
+
+using Microsoft.Extensions.Logging;
+
+namespace WireMock.Logging;
+
+internal sealed class WireMockAspNetCoreLogger(IWireMockLogger logger, string categoryName) : ILogger
+{
+    public IDisposable? BeginScope<TState>(TState state) where TState : notnull => null;
+
+    public bool IsEnabled(LogLevel logLevel) => logLevel >= LogLevel.Warning;
+
+    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
+    {
+        if (!IsEnabled(logLevel))
+        {
+            return;
+        }
+
+        var message = formatter(state, exception);
+
+        if (exception != null)
+        {
+            message = $"{message} | Exception: {exception}";
+        }
+
+        switch (logLevel)
+        {
+            case LogLevel.Warning:
+                logger.Warn("[{0}] {1}", categoryName, message);
+                break;
+
+            default:
+                logger.Error("[{0}] {1}", categoryName, message);
+                break;
+        }
+    }
+}

src/WireMock.Net.Minimal/Logging/WireMockAspNetCoreLoggerProvider.cs

@@ -0,0 +1,19 @@
+// Copyright © WireMock.Net
+
+using Microsoft.Extensions.Logging;
+
+namespace WireMock.Logging;
+
+internal sealed class WireMockAspNetCoreLoggerProvider : ILoggerProvider
+{
+    private readonly IWireMockLogger _logger;
+
+    public WireMockAspNetCoreLoggerProvider(IWireMockLogger logger)
+    {
+        _logger = logger;
+    }
+
+    public ILogger CreateLogger(string categoryName) => new WireMockAspNetCoreLogger(_logger, categoryName);
+
+    public void Dispose() { }
+}

src/WireMock.Net.Minimal/Mapping.cs

@@ -62,6 +62,9 @@ public class Mapping : IMapping
     /// <inheritdoc />
     public bool IsProxy => Provider is ProxyAsyncResponseProvider;
 
+    /// <inheritdoc />
+    public bool IsDisabled { get; set; }
+
     /// <inheritdoc />
     public bool LogMapping => Provider is not (DynamicResponseProvider or DynamicAsyncResponseProvider);
 

src/WireMock.Net.Minimal/Matchers/Request/RequestMatchResult.cs

@@ -1,7 +1,5 @@
 // Copyright © WireMock.Net
 
-using System.Linq;
-
 namespace WireMock.Matchers.Request;
 
 /// <summary>
@@ -30,7 +28,7 @@ public class RequestMatchResult : IRequestMatchResult
         return AddMatchDetail(new MatchDetail
         {
             Name = matcherType.Name.Replace("RequestMessage", string.Empty),
-            MatcherType = matcherType,
+            MatcherType = matcherType.Name,
             Score = score,
             Exception = exception
         });

src/WireMock.Net.Minimal/Owin/AspNetCoreSelfHost.cs

@@ -1,9 +1,9 @@
 // Copyright © WireMock.Net
 
-using System.Linq;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Logging;
 using Stef.Validation;
 using WireMock.Logging;
 using WireMock.Owin.Mappers;
@@ -57,6 +57,12 @@ internal partial class AspNetCoreSelfHost
         _host = builder
             .UseSetting("suppressStatusMessages", "True") // https://andrewlock.net/suppressing-the-startup-and-shutdown-messages-in-asp-net-core/
             .ConfigureAppConfigurationUsingEnvironmentVariables()
+            .ConfigureLogging(logging =>
+            {
+                logging.ClearProviders();
+                logging.AddProvider(new WireMockAspNetCoreLoggerProvider(_logger));
+                logging.SetMinimumLevel(LogLevel.Warning);
+            })
             .ConfigureServices(services =>
             {
                 services.AddSingleton(_wireMockMiddlewareOptions);
@@ -169,10 +175,10 @@ internal partial class AspNetCoreSelfHost
 
             return _host.RunAsync(token);
         }
-        catch (Exception e)
+        catch (Exception ex)
         {
-            RunningException = e;
+            RunningException = ex;
-            _logger.Error(e.ToString());
+            _logger.Error("Error while RunAsync", ex);
 
             IsStarted = false;
 

src/WireMock.Net.Minimal/Owin/IWireMockMiddlewareOptions.cs

@@ -2,6 +2,7 @@
 
 using System.Collections.Concurrent;
 using System.Security.Cryptography.X509Certificates;
+using JsonConverter.Abstractions;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.Extensions.DependencyInjection;
 using WireMock.Handlers;
@@ -27,7 +28,7 @@ internal interface IWireMockMiddlewareOptions
 
     ConcurrentDictionary<Guid, IMapping> Mappings { get; }
 
-    ConcurrentDictionary<string, ScenarioState> Scenarios { get; }
+    IScenarioStateStore ScenarioStateStore { get; set; }
 
     ConcurrentObservableCollection<LogEntry> LogEntries { get; }
 
@@ -99,4 +100,12 @@ internal interface IWireMockMiddlewareOptions
     /// WebSocket settings.
     /// </summary>
     WebSocketSettings? WebSocketSettings { get; set; }
+
+    /// <summary>
+    /// Gets or sets the default JSON converter used for serialization.
+    /// </summary>
+    /// <remarks>
+    /// Set this property to customize how objects are serialized to and deserialized from JSON during mapping.
+    /// </remarks>
+    IJsonConverter DefaultJsonSerializer { get; set; }
 }

src/WireMock.Net.Minimal/Owin/Mappers/OwinResponseMapper.cs

@@ -1,257 +1,244 @@
 // Copyright © WireMock.Net
 
 using System.Globalization;
-using System.Linq;
 using System.Net;
-using System.Reflection;
 using System.Text;
+using JsonConverter.Abstractions;
 using Microsoft.AspNetCore.Http;
-using Newtonsoft.Json;
 using RandomDataGenerator.FieldOptions;
 using RandomDataGenerator.Randomizers;
-using Stef.Validation;
 using WireMock.Http;
 using WireMock.ResponseBuilders;
 using WireMock.ResponseProviders;
 using WireMock.Types;
 using WireMock.Util;
 
-namespace WireMock.Owin.Mappers
+namespace WireMock.Owin.Mappers;
+
+/// <summary>
+/// OwinResponseMapper
+/// </summary>
+internal class OwinResponseMapper(IWireMockMiddlewareOptions options) : IOwinResponseMapper
 {
-    /// <summary>
+    private readonly IRandomizerNumber<double> _randomizerDouble = RandomizerFactory.GetRandomizer(new FieldOptionsDouble { Min = 0, Max = 1 });
-    /// OwinResponseMapper
+    private readonly IRandomizerBytes _randomizerBytes = RandomizerFactory.GetRandomizer(new FieldOptionsBytes { Min = 100, Max = 200 });
-    /// </summary>
+    private readonly Encoding _utf8NoBom = new UTF8Encoding(false);
-    internal class OwinResponseMapper : IOwinResponseMapper
+
+    // https://msdn.microsoft.com/en-us/library/78h415ay(v=vs.110).aspx
+    private static readonly IDictionary<string, Action<HttpResponse, bool, WireMockList<string>>> ResponseHeadersToFix =
+        new Dictionary<string, Action<HttpResponse, bool, WireMockList<string>>>(StringComparer.OrdinalIgnoreCase)
+        {
+            { HttpKnownHeaderNames.ContentType, (r, _, v) => r.ContentType = v.FirstOrDefault() },
+            { HttpKnownHeaderNames.ContentLength, (r, hasBody, v) =>
+                {
+                    // Only set the Content-Length header if the response does not have a body
+                    if (!hasBody && long.TryParse(v.FirstOrDefault(), out var contentLength))
+                    {
+                        r.ContentLength = contentLength;
+                    }
+                }
+            }
+        };
+
+    /// <inheritdoc />
+    public async Task MapAsync(IResponseMessage? responseMessage, HttpResponse response)
     {
-        private readonly IRandomizerNumber<double> _randomizerDouble = RandomizerFactory.GetRandomizer(new FieldOptionsDouble { Min = 0, Max = 1 });
+        if (responseMessage == null || responseMessage is WebSocketHandledResponse)
-        private readonly IRandomizerBytes _randomizerBytes = RandomizerFactory.GetRandomizer(new FieldOptionsBytes { Min = 100, Max = 200 });
-        private readonly IWireMockMiddlewareOptions _options;
-        private readonly Encoding _utf8NoBom = new UTF8Encoding(false);
-
-        // https://msdn.microsoft.com/en-us/library/78h415ay(v=vs.110).aspx
-        private static readonly IDictionary<string, Action<HttpResponse, bool, WireMockList<string>>> ResponseHeadersToFix =
-            new Dictionary<string, Action<HttpResponse, bool, WireMockList<string>>>(StringComparer.OrdinalIgnoreCase)
-            {
-                { HttpKnownHeaderNames.ContentType, (r, _, v) => r.ContentType = v.FirstOrDefault() },
-                { HttpKnownHeaderNames.ContentLength, (r, hasBody, v) =>
-                    {
-                        // Only set the Content-Length header if the response does not have a body
-                        if (!hasBody && long.TryParse(v.FirstOrDefault(), out var contentLength))
-                        {
-                            r.ContentLength = contentLength;
-                        }
-                    }
-                }
-            };
-
-        /// <summary>
-        /// Constructor
-        /// </summary>
-        /// <param name="options">The IWireMockMiddlewareOptions.</param>
-        public OwinResponseMapper(IWireMockMiddlewareOptions options)
         {
-            _options = Guard.NotNull(options);
+            return;
         }
 
-        /// <inheritdoc />
+        var bodyData = responseMessage.BodyData;
-        public async Task MapAsync(IResponseMessage? responseMessage, HttpResponse response)
+        if (bodyData?.GetDetectedBodyType() == BodyType.SseString)
         {
-            if (responseMessage == null || responseMessage is WebSocketHandledResponse)
+            await HandleSseStringAsync(responseMessage, response, bodyData);
-            {
+            return;
-                return;
-            }
-
-            var bodyData = responseMessage.BodyData;
-            if (bodyData?.GetDetectedBodyType() == BodyType.SseString)
-            {
-                await HandleSseStringAsync(responseMessage, response, bodyData);
-                return;
-            }
-
-            byte[]? bytes;
-            switch (responseMessage.FaultType)
-            {
-                case FaultType.EMPTY_RESPONSE:
-                    bytes = IsFault(responseMessage) ? [] : await GetNormalBodyAsync(responseMessage).ConfigureAwait(false);
-                    break;
-
-                case FaultType.MALFORMED_RESPONSE_CHUNK:
-                    bytes = await GetNormalBodyAsync(responseMessage).ConfigureAwait(false) ?? [];
-                    if (IsFault(responseMessage))
-                    {
-                        bytes = bytes.Take(bytes.Length / 2).Union(_randomizerBytes.Generate()).ToArray();
-                    }
-                    break;
-
-                default:
-                    bytes = await GetNormalBodyAsync(responseMessage).ConfigureAwait(false);
-                    break;
-            }
-
-            var statusCodeType = responseMessage.StatusCode?.GetType();
-            if (statusCodeType != null)
-            {
-                if (statusCodeType == typeof(int) || statusCodeType == typeof(int?) || statusCodeType.GetTypeInfo().IsEnum)
-                {
-                    response.StatusCode = MapStatusCode((int)responseMessage.StatusCode!);
-                }
-                else if (statusCodeType == typeof(string))
-                {
-                    // Note: this case will also match on null
-                    int.TryParse(responseMessage.StatusCode as string, out var statusCodeTypeAsInt);
-                    response.StatusCode = MapStatusCode(statusCodeTypeAsInt);
-                }
-            }
-
-            SetResponseHeaders(responseMessage, bytes != null, response);
-
-            if (bytes != null)
-            {
-                try
-                {
-                    await response.Body.WriteAsync(bytes, 0, bytes.Length).ConfigureAwait(false);
-                }
-                catch (Exception ex)
-                {
-                    _options.Logger.Warn("Error writing response body. Exception : {0}", ex);
-                }
-            }
-
-            SetResponseTrailingHeaders(responseMessage, response);
         }
 
-        private static async Task HandleSseStringAsync(IResponseMessage responseMessage, HttpResponse response, IBodyData bodyData)
+        byte[]? bytes;
+        switch (responseMessage.FaultType)
         {
-            if (bodyData.SseStringQueue == null)
+            case FaultType.EMPTY_RESPONSE:
-            {
+                bytes = IsFault(responseMessage) ? [] : await GetNormalBodyAsync(responseMessage).ConfigureAwait(false);
-                return;
+                break;
-            }
 
-            SetResponseHeaders(responseMessage, true, response);
+            case FaultType.MALFORMED_RESPONSE_CHUNK:
-
+                bytes = await GetNormalBodyAsync(responseMessage).ConfigureAwait(false) ?? [];
-            string? text;
+                if (IsFault(responseMessage))
-            do
-            {
-                if (bodyData.SseStringQueue.TryRead(out text))
                 {
-                    await response.WriteAsync(text);
+                    bytes = bytes.Take(bytes.Length / 2).Union(_randomizerBytes.Generate()).ToArray();
-                    await response.Body.FlushAsync();
                 }
-            } while (text != null);
+                break;
+
+            default:
+                bytes = await GetNormalBodyAsync(responseMessage).ConfigureAwait(false);
+                break;
         }
 
-        private int MapStatusCode(int code)
+        if (responseMessage.StatusCode is HttpStatusCode or int)
         {
-            if (_options.AllowOnlyDefinedHttpStatusCodeInResponse == true && !Enum.IsDefined(typeof(HttpStatusCode), code))
+            response.StatusCode = MapStatusCode((int)responseMessage.StatusCode);
+        }
+        else if (responseMessage.StatusCode is string statusCodeAsString)
+        {
+            // Note: this case will also match on null
+            _ = int.TryParse(statusCodeAsString, out var statusCodeTypeAsInt);
+            response.StatusCode = MapStatusCode(statusCodeTypeAsInt);
+        }
+
+        SetResponseHeaders(responseMessage, bytes != null, response);
+
+        if (bytes != null)
+        {
+            try
             {
-                return (int)HttpStatusCode.OK;
+                await response.Body.WriteAsync(bytes, 0, bytes.Length).ConfigureAwait(false);
             }
-
+            catch (Exception ex)
-            return code;
-        }
-
-        private bool IsFault(IResponseMessage responseMessage)
-        {
-            return responseMessage.FaultPercentage == null || _randomizerDouble.Generate() <= responseMessage.FaultPercentage;
-        }
-
-        private async Task<byte[]?> GetNormalBodyAsync(IResponseMessage responseMessage)
-        {
-            var bodyData = responseMessage.BodyData;
-            switch (bodyData?.GetDetectedBodyType())
             {
-                case BodyType.String:
+                options.Logger.Warn("Error writing response body. Exception : {0}", ex);
-                case BodyType.FormUrlEncoded:
-                    return (bodyData.Encoding ?? _utf8NoBom).GetBytes(bodyData.BodyAsString!);
-
-                case BodyType.Json:
-                    var formatting = bodyData.BodyAsJsonIndented == true ? Formatting.Indented : Formatting.None;
-                    var jsonBody = JsonConvert.SerializeObject(bodyData.BodyAsJson, new JsonSerializerSettings { Formatting = formatting, NullValueHandling = NullValueHandling.Ignore });
-                    return (bodyData.Encoding ?? _utf8NoBom).GetBytes(jsonBody);
-
-                case BodyType.ProtoBuf:
-                    if (TypeLoader.TryLoadStaticInstance<IProtoBufUtils>(out var protoBufUtils))
-                    {
-                        var protoDefinitions = bodyData.ProtoDefinition?.Invoke().Texts;
-                        return await protoBufUtils.GetProtoBufMessageWithHeaderAsync(protoDefinitions, bodyData.ProtoBufMessageType, bodyData.BodyAsJson).ConfigureAwait(false);
-                    }
-                    break;
-
-                case BodyType.Bytes:
-                    return bodyData.BodyAsBytes;
-
-                case BodyType.File:
-                    return _options.FileSystemHandler?.ReadResponseBodyAsFile(bodyData.BodyAsFile!);
-
-                case BodyType.MultiPart:
-                    _options.Logger.Warn("MultiPart body type is not handled!");
-                    break;
-
-                case BodyType.None:
-                    break;
-            }
-
-            return null;
-        }
-
-        private static void SetResponseHeaders(IResponseMessage responseMessage, bool hasBody, HttpResponse response)
-        {
-            // Force setting the Date header (#577)
-            AppendResponseHeader(
-                response,
-                HttpKnownHeaderNames.Date,
-                [DateTime.UtcNow.ToString(CultureInfo.InvariantCulture.DateTimeFormat.RFC1123Pattern, CultureInfo.InvariantCulture)]
-            );
-
-            // Set other headers
-            foreach (var item in responseMessage.Headers!)
-            {
-                var headerName = item.Key;
-                var value = item.Value;
-                if (ResponseHeadersToFix.TryGetValue(headerName, out var action))
-                {
-                    action.Invoke(response, hasBody, value);
-                }
-                else
-                {
-                    // Check if this response header can be added (#148, #227 and #720)
-                    if (!HttpKnownHeaderNames.IsRestrictedResponseHeader(headerName))
-                    {
-                        AppendResponseHeader(response, headerName, value.ToArray());
-                    }
-                }
             }
         }
 
-        private static void SetResponseTrailingHeaders(IResponseMessage responseMessage, HttpResponse response)
+        SetResponseTrailingHeaders(responseMessage, response);
-        {
+    }
-            if (responseMessage.TrailingHeaders == null)
-            {
-                return;
-            }
 
-#if TRAILINGHEADERS
+    private static async Task HandleSseStringAsync(IResponseMessage responseMessage, HttpResponse response, IBodyData bodyData)
-            foreach (var (headerName, value) in responseMessage.TrailingHeaders)
+    {
-            {
+        if (bodyData.SseStringQueue == null)
-                if (ResponseHeadersToFix.TryGetValue(headerName, out var action))
+        {
-                {
+            return;
-                    action.Invoke(response, false, value);
-                }
-                else
-                {
-                    // Check if this trailing header can be added to the response
-                    if (response.SupportsTrailers() && !HttpKnownHeaderNames.IsRestrictedResponseHeader(headerName))
-                    {
-                        response.AppendTrailer(headerName, new Microsoft.Extensions.Primitives.StringValues(value.ToArray()));
-                    }
-                }
-            }
-#endif
         }
 
-        private static void AppendResponseHeader(HttpResponse response, string headerName, string[] values)
+        SetResponseHeaders(responseMessage, true, response);
+
+        string? text;
+        do
         {
-            response.Headers.Append(headerName, values);
+            if (bodyData.SseStringQueue.TryRead(out text))
+            {
+                await response.WriteAsync(text);
+                await response.Body.FlushAsync();
+            }
+        } while (text != null);
+    }
+
+    private int MapStatusCode(int code)
+    {
+        if (options.AllowOnlyDefinedHttpStatusCodeInResponse == true && !Enum.IsDefined(typeof(HttpStatusCode), code))
+        {
+            return (int)HttpStatusCode.OK;
+        }
+
+        return code;
+    }
+
+    private bool IsFault(IResponseMessage responseMessage)
+    {
+        return responseMessage.FaultPercentage == null || _randomizerDouble.Generate() <= responseMessage.FaultPercentage;
+    }
+
+    private async Task<byte[]?> GetNormalBodyAsync(IResponseMessage responseMessage)
+    {
+        var bodyData = responseMessage.BodyData;
+        switch (bodyData?.GetDetectedBodyType())
+        {
+            case BodyType.String:
+            case BodyType.FormUrlEncoded:
+                return (bodyData.Encoding ?? _utf8NoBom).GetBytes(bodyData.BodyAsString!);
+
+            case BodyType.Json:
+                var jsonConverterOptions = new JsonConverterOptions
+                {
+                    WriteIndented = bodyData.BodyAsJsonIndented == true,
+                    IgnoreNullValues = true
+                };
+
+                var jsonBody = options.DefaultJsonSerializer.Serialize(bodyData.BodyAsJson!, jsonConverterOptions);
+                return (bodyData.Encoding ?? _utf8NoBom).GetBytes(jsonBody);
+
+            case BodyType.ProtoBuf:
+                if (TypeLoader.TryLoadStaticInstance<IProtoBufUtils>(out var protoBufUtils))
+                {
+                    var protoDefinitions = bodyData.ProtoDefinition?.Invoke().Texts;
+                    return await protoBufUtils.GetProtoBufMessageWithHeaderAsync(protoDefinitions, bodyData.ProtoBufMessageType, bodyData.BodyAsJson).ConfigureAwait(false);
+                }
+                break;
+
+            case BodyType.Bytes:
+                return bodyData.BodyAsBytes;
+
+            case BodyType.File:
+                return options.FileSystemHandler?.ReadResponseBodyAsFile(bodyData.BodyAsFile!);
+
+            case BodyType.MultiPart:
+                options.Logger.Warn("MultiPart body type is not handled!");
+                break;
+
+            case BodyType.None:
+                break;
+        }
+
+        return null;
+    }
+
+    private static void SetResponseHeaders(IResponseMessage responseMessage, bool hasBody, HttpResponse response)
+    {
+        // Force setting the Date header (#577)
+        AppendResponseHeader(
+            response,
+            HttpKnownHeaderNames.Date,
+            [DateTime.UtcNow.ToString(CultureInfo.InvariantCulture.DateTimeFormat.RFC1123Pattern, CultureInfo.InvariantCulture)]
+        );
+
+        // Set other headers
+        foreach (var item in responseMessage.Headers!)
+        {
+            var headerName = item.Key;
+            var value = item.Value;
+            if (ResponseHeadersToFix.TryGetValue(headerName, out var action))
+            {
+                action.Invoke(response, hasBody, value);
+            }
+            else
+            {
+                // Check if this response header can be added (#148, #227 and #720)
+                if (!HttpKnownHeaderNames.IsRestrictedResponseHeader(headerName))
+                {
+                    AppendResponseHeader(response, headerName, value.ToArray());
+                }
+            }
         }
     }
+
+    private static void SetResponseTrailingHeaders(IResponseMessage responseMessage, HttpResponse response)
+    {
+        if (responseMessage.TrailingHeaders == null)
+        {
+            return;
+        }
+
+#if TRAILINGHEADERS
+        foreach (var (headerName, value) in responseMessage.TrailingHeaders)
+        {
+            if (ResponseHeadersToFix.TryGetValue(headerName, out var action))
+            {
+                action.Invoke(response, false, value);
+            }
+            else
+            {
+                // Check if this trailing header can be added to the response
+                if (response.SupportsTrailers() && !HttpKnownHeaderNames.IsRestrictedResponseHeader(headerName))
+                {
+                    response.AppendTrailer(headerName, new Microsoft.Extensions.Primitives.StringValues(value.ToArray()));
+                }
+            }
+        }
+#endif
+    }
+
+    private static void AppendResponseHeader(HttpResponse response, string headerName, string[] values)
+    {
+        response.Headers.Append(headerName, values);
+    }
 }

src/WireMock.Net.Minimal/Owin/MappingMatcher.cs

@@ -19,6 +19,7 @@ internal class MappingMatcher(IWireMockMiddlewareOptions options, IRandomizerDou
         var possibleMappings = new List<MappingMatcherResult>();
 
         var mappings = _options.Mappings.Values
+            .Where(m => !m.IsDisabled)
             .Where(m => m.TimeSettings.IsValid())
             .Where(m => m.Probability is null || _randomizerDoubleBetween0And1.Generate() <= m.Probability)
             .ToArray();
@@ -89,14 +90,13 @@ internal class MappingMatcher(IWireMockMiddlewareOptions options, IRandomizerDou
 
     private string? GetNextState(IMapping mapping)
     {
-        // If the mapping does not have a scenario or _options.Scenarios does not contain this scenario from the mapping,
+        // If the mapping does not have a scenario or the store does not contain this scenario,
         // just return null to indicate that there is no next state.
-        if (mapping.Scenario == null || !_options.Scenarios.ContainsKey(mapping.Scenario))
+        if (mapping.Scenario == null)
         {
             return null;
         }
 
-        // Else just return the next state
+        return _options.ScenarioStateStore.TryGet(mapping.Scenario, out var state) ? state.NextState : null;
-        return _options.Scenarios[mapping.Scenario].NextState;
     }
 }

src/WireMock.Net.Minimal/Owin/WireMockMiddleware.cs

@@ -81,9 +81,9 @@ internal class WireMockMiddleware(
                 }
 
                 // Set scenario start
-                if (!options.Scenarios.ContainsKey(mapping.Scenario) && mapping.IsStartState)
+                if (!options.ScenarioStateStore.ContainsKey(mapping.Scenario) && mapping.IsStartState)
                 {
-                    options.Scenarios.TryAdd(mapping.Scenario, new ScenarioState
+                    options.ScenarioStateStore.TryAdd(mapping.Scenario, new ScenarioState
                     {
                         Name = mapping.Scenario
                     });
@@ -122,6 +122,14 @@ internal class WireMockMiddleware(
                 }
             }
 
+            // Transition scenario state immediately after matching, before any delay (global or
+            // per-mapping) so that concurrent retries arriving during a delay period see the
+            // updated state and match the correct next mapping instead of re-matching this one.
+            if (targetMapping.Scenario != null)
+            {
+                UpdateScenarioState(targetMapping);
+            }
+
             if (!targetMapping.IsAdminInterface && options.RequestProcessingDelay > TimeSpan.Zero)
             {
                 await Task.Delay(options.RequestProcessingDelay.Value).ConfigureAwait(false);
@@ -147,11 +155,6 @@ internal class WireMockMiddleware(
                 }
             }
 
-            if (targetMapping.Scenario != null)
-            {
-                UpdateScenarioState(targetMapping);
-            }
-
             if (!targetMapping.IsAdminInterface && targetMapping.Webhooks?.Length > 0)
             {
                 await SendToWebhooksAsync(targetMapping, request, response).ConfigureAwait(false);
@@ -233,20 +236,21 @@ internal class WireMockMiddleware(
 
     private void UpdateScenarioState(IMapping mapping)
     {
-        var scenario = options.Scenarios[mapping.Scenario!];
+        options.ScenarioStateStore.Update(mapping.Scenario!, scenario =>
-
-        // Increase the number of times this state has been executed
-        scenario.Counter++;
-
-        // Only if the number of times this state is executed equals the required StateTimes, proceed to next state and reset the counter to 0
-        if (scenario.Counter == (mapping.TimesInSameState ?? 1))
         {
-            scenario.NextState = mapping.NextState;
+            // Increase the number of times this state has been executed
-            scenario.Counter = 0;
+            scenario.Counter++;
-        }
 
-        // Else just update Started and Finished
+            // Only if the number of times this state is executed equals the required StateTimes, proceed to next state and reset the counter to 0
-        scenario.Started = true;
+            if (scenario.Counter == (mapping.TimesInSameState ?? 1))
-        scenario.Finished = mapping.NextState == null;
+            {
+                scenario.NextState = mapping.NextState;
+                scenario.Counter = 0;
+            }
+
+            // Else just update Started and Finished
+            scenario.Started = true;
+            scenario.Finished = mapping.NextState == null;
+        });
     }
-}
+}

src/WireMock.Net.Minimal/Owin/WireMockMiddlewareOptions.cs

@@ -2,6 +2,8 @@
 
 using System.Collections.Concurrent;
 using System.Security.Cryptography.X509Certificates;
+using JsonConverter.Abstractions;
+using JsonConverter.Newtonsoft.Json;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.Extensions.DependencyInjection;
 using WireMock.Handlers;
@@ -27,7 +29,7 @@ internal class WireMockMiddlewareOptions : IWireMockMiddlewareOptions
 
     public ConcurrentDictionary<Guid, IMapping> Mappings { get; } = new ConcurrentDictionary<Guid, IMapping>();
 
-    public ConcurrentDictionary<string, ScenarioState> Scenarios { get; } = new(StringComparer.OrdinalIgnoreCase);
+    public IScenarioStateStore ScenarioStateStore { get; set; } = new InMemoryScenarioStateStore();
 
     public ConcurrentObservableCollection<LogEntry> LogEntries { get; } = new();
 
@@ -108,5 +110,9 @@ internal class WireMockMiddlewareOptions : IWireMockMiddlewareOptions
     /// <inheritdoc />
     public ConcurrentDictionary<Guid, WebSocketConnectionRegistry> WebSocketRegistries { get; } = new();
 
+    /// <inheritdoc />
     public WebSocketSettings? WebSocketSettings { get; set; }
+
+    /// <inheritdoc />
+    public IJsonConverter DefaultJsonSerializer { get; set; } = new NewtonsoftJsonConverter();
 }

src/WireMock.Net.Minimal/Owin/WireMockMiddlewareOptionsHelper.cs

@@ -27,6 +27,7 @@ internal static class WireMockMiddlewareOptionsHelper
         options.FileSystemHandler = settings.FileSystemHandler;
         options.HandleRequestsSynchronously = settings.HandleRequestsSynchronously;
         options.Logger = settings.Logger;
+        options.ScenarioStateStore = settings.ScenarioStateStore;
         options.MaxRequestLogCount = settings.MaxRequestLogCount;
         options.PostWireMockMiddlewareInit = settings.PostWireMockMiddlewareInit;
         options.PreWireMockMiddlewareInit = settings.PreWireMockMiddlewareInit;

src/WireMock.Net.Minimal/Serialization/MappingConverter.cs

@@ -275,6 +275,7 @@ internal class MappingConverter(MatcherMapper mapper)
             TimesInSameState = !string.IsNullOrWhiteSpace(mapping.NextState) ? mapping.TimesInSameState : null,
             Data = mapping.Data,
             Probability = mapping.Probability,
+            IsDisabled = mapping.IsDisabled ? true : null,
             Request = new RequestModel
             {
                 Headers = headerMatchers.Any() ? headerMatchers.Select(hm => new HeaderModel

src/WireMock.Net.Minimal/Serialization/MappingSerializer.cs

@@ -1,6 +1,7 @@
 // Copyright © WireMock.Net
 
 using JsonConverter.Abstractions;
+using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 #if NETSTANDARD2_0_OR_GREATER || NETCOREAPP3_1_OR_GREATER || NET6_0_OR_GREATER || NET461
 using System.Text.Json;
@@ -10,9 +11,15 @@ namespace WireMock.Serialization;
 
 internal class MappingSerializer(IJsonConverter jsonConverter)
 {
+    private static readonly JsonConverterOptions JsonConverterOptions = new JsonConverterOptions
+    {
+        DateParseHandling = (int) DateParseHandling.None
+    };
+
     internal T[] DeserializeJsonToArray<T>(string value)
     {
-        return DeserializeObjectToArray<T>(jsonConverter.Deserialize<object>(value)!);
+        // DeserializeObject
+        return DeserializeObjectToArray<T>(jsonConverter.Deserialize<object>(value, JsonConverterOptions)!);
     }
 
     internal static T[] DeserializeObjectToArray<T>(object value)

src/WireMock.Net.Minimal/Server/IRespondWithAProvider.cs

@@ -234,6 +234,13 @@ public interface IRespondWithAProvider
     /// <returns>The <see cref="IRespondWithAProvider"/>.</returns>
     IRespondWithAProvider WithProbability(double probability);
 
+    /// <summary>
+    /// Define whether this mapping is disabled. Defaults to <c>false</c>.
+    /// </summary>
+    /// <param name="isDisabled">Whether this mapping is disabled.</param>
+    /// <returns>The <see cref="IRespondWithAProvider"/>.</returns>
+    IRespondWithAProvider WithIsDisabled(bool isDisabled);
+
     /// <summary>
     /// Define a Grpc ProtoDefinition which is used for the request and the response.
     /// This can be a ProtoDefinition as a string, or an id when the ProtoDefinitions are defined at the WireMockServer.

src/WireMock.Net.Minimal/Server/RespondWithAProvider.cs

@@ -37,6 +37,7 @@ internal class RespondWithAProvider : IRespondWithAProvider
     private int _timesInSameState = 1;
     private bool? _useWebhookFireAndForget;
     private double? _probability;
+    private bool _isDisabled = false;
     private GraphQLSchemaDetails? _graphQLSchemaDetails; // Future Use.
 
     public Guid Guid { get; private set; }
@@ -108,6 +109,11 @@ internal class RespondWithAProvider : IRespondWithAProvider
             mapping.WithProbability(_probability.Value);
         }
 
+        if (_isDisabled)
+        {
+            mapping.IsDisabled = true;
+        }
+
         if (ProtoDefinition != null)
         {
             mapping.WithProtoDefinition(ProtoDefinition.Value);
@@ -354,6 +360,13 @@ internal class RespondWithAProvider : IRespondWithAProvider
         return this;
     }
 
+    /// <inheritdoc />
+    public IRespondWithAProvider WithIsDisabled(bool isDisabled)
+    {
+        _isDisabled = isDisabled;
+        return this;
+    }
+
     /// <inheritdoc />
     public IRespondWithAProvider WithProtoDefinition(params string[] protoDefinitionOrId)
     {

src/WireMock.Net.Minimal/Server/WireMockServer.Admin.cs

@@ -1,6 +1,5 @@
 // Copyright © WireMock.Net
 
-using System.Linq;
 using System.Net;
 using System.Text;
 using JetBrains.Annotations;
@@ -26,9 +25,6 @@ using WireMock.Util;
 
 namespace WireMock.Server;
 
-/// <summary>
-/// The fluent mock server.
-/// </summary>
 public partial class WireMockServer
 {
     private const int EnhancedFileSystemWatcherTimeoutMs = 1000;
@@ -61,6 +57,8 @@ public partial class WireMockServer
         public string OpenApi => $"{_prefix}/openapi";
 
         public RegexMatcher MappingsGuidPathMatcher => new($"^{_prefixEscaped}\\/mappings\\/([0-9A-Fa-f]{{8}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{12}})$");
+        public RegexMatcher MappingsGuidEnablePathMatcher  => new($"^{_prefixEscaped}\\/mappings\\/([0-9A-Fa-f]{{8}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{12}})\\/enable$");
+        public RegexMatcher MappingsGuidDisablePathMatcher => new($"^{_prefixEscaped}\\/mappings\\/([0-9A-Fa-f]{{8}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{12}})\\/disable$");
         public RegexMatcher MappingsCodeGuidPathMatcher => new($"^{_prefixEscaped}\\/mappings\\/code\\/([0-9A-Fa-f]{{8}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{12}})$");
         public RegexMatcher RequestsGuidPathMatcher => new($"^{_prefixEscaped}\\/requests\\/([0-9A-Fa-f]{{8}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{4}}[-][0-9A-Fa-f]{{12}})$");
         public RegexMatcher ScenariosNameMatcher => new($"^{_prefixEscaped}\\/scenarios\\/.+$");
@@ -104,6 +102,12 @@ public partial class WireMockServer
         Given(Request.Create().WithPath(_adminPaths.MappingsGuidPathMatcher).UsingPut().WithHeader(HttpKnownHeaderNames.ContentType, AdminRequestContentTypeJson)).AtPriority(WireMockConstants.AdminPriority).RespondWith(new DynamicResponseProvider(MappingPut));
         Given(Request.Create().WithPath(_adminPaths.MappingsGuidPathMatcher).UsingDelete()).AtPriority(WireMockConstants.AdminPriority).RespondWith(new DynamicResponseProvider(MappingDelete));
 
+        // __admin/mappings/{guid}/enable
+        Given(Request.Create().WithPath(_adminPaths.MappingsGuidEnablePathMatcher).UsingPut()).AtPriority(WireMockConstants.AdminPriority).RespondWith(new DynamicResponseProvider(MappingEnable));
+
+        // __admin/mappings/{guid}/disable
+        Given(Request.Create().WithPath(_adminPaths.MappingsGuidDisablePathMatcher).UsingPut()).AtPriority(WireMockConstants.AdminPriority).RespondWith(new DynamicResponseProvider(MappingDisable));
+
         // __admin/mappings/code/{guid}
         Given(Request.Create().WithPath(_adminPaths.MappingsCodeGuidPathMatcher).UsingGet()).AtPriority(WireMockConstants.AdminPriority).RespondWith(new DynamicResponseProvider(MappingCodeGet));
 
@@ -430,6 +434,47 @@ public partial class WireMockServer
         var lastPart = requestMessage.Path.Split('/').LastOrDefault();
         return Guid.TryParse(lastPart, out guid);
     }
+
+    private static bool TryParseGuidFromSecondToLastSegment(IRequestMessage requestMessage, out Guid guid)
+    {
+        var parts = requestMessage.Path.Split('/');
+        if (parts.Length >= 2 && Guid.TryParse(parts[parts.Length - 2], out guid))
+            return true;
+        guid = Guid.Empty;
+        return false;
+    }
+
+    private IResponseMessage MappingEnable(HttpContext _, IRequestMessage requestMessage)
+    {
+        if (TryParseGuidFromSecondToLastSegment(requestMessage, out var guid))
+        {
+            var mapping = Mappings.FirstOrDefault(m => !m.IsAdminInterface && m.Guid == guid);
+            if (mapping != null)
+            {
+                mapping.IsDisabled = false;
+                return ResponseMessageBuilder.Create(HttpStatusCode.OK, "Mapping enabled", guid);
+            }
+        }
+
+        _settings.Logger.Warn("HttpStatusCode set to 404 : Mapping not found");
+        return ResponseMessageBuilder.Create(HttpStatusCode.NotFound, "Mapping not found");
+    }
+
+    private IResponseMessage MappingDisable(HttpContext _, IRequestMessage requestMessage)
+    {
+        if (TryParseGuidFromSecondToLastSegment(requestMessage, out var guid))
+        {
+            var mapping = Mappings.FirstOrDefault(m => !m.IsAdminInterface && m.Guid == guid);
+            if (mapping != null)
+            {
+                mapping.IsDisabled = true;
+                return ResponseMessageBuilder.Create(HttpStatusCode.OK, "Mapping disabled", guid);
+            }
+        }
+
+        _settings.Logger.Warn("HttpStatusCode set to 404 : Mapping not found");
+        return ResponseMessageBuilder.Create(HttpStatusCode.NotFound, "Mapping not found");
+    }
     #endregion Mapping/{guid}
 
     #region Mappings
@@ -672,7 +717,7 @@ public partial class WireMockServer
     #region Scenarios
     private IResponseMessage ScenariosGet(HttpContext _, IRequestMessage requestMessage)
     {
-        var scenariosStates = Scenarios.Values.Select(s => new ScenarioStateModel
+        var scenariosStates = Scenarios.Select(s => new ScenarioStateModel
         {
             Name = s.Name,
             NextState = s.NextState,
@@ -705,7 +750,7 @@ public partial class WireMockServer
     private IResponseMessage ScenariosSetState(HttpContext _, IRequestMessage requestMessage)
     {
         var name = Enumerable.Reverse(requestMessage.Path.Split('/')).Skip(1).First();
-        if (!_options.Scenarios.ContainsKey(name))
+        if (!_options.ScenarioStateStore.ContainsKey(name))
         {
             ResponseMessageBuilder.Create(HttpStatusCode.NotFound, $"No scenario found by name '{name}'.");
         }

src/WireMock.Net.Minimal/Server/WireMockServer.ConvertMapping.cs

@@ -120,6 +120,11 @@ public partial class WireMockServer
             respondProvider.WithProbability(mappingModel.Probability.Value);
         }
 
+        if (mappingModel.IsDisabled == true)
+        {
+            respondProvider.WithIsDisabled(true);
+        }
+
         // ProtoDefinition is defined at Mapping level
         if (mappingModel.ProtoDefinition != null)
         {

src/WireMock.Net.Minimal/Transformers/Scriban/WireMockListAccessor.cs

@@ -19,7 +19,7 @@ internal class WireMockListAccessor : IListAccessor, IObjectAccessor
         return target?.ToString() ?? string.Empty;
     }
 
-    public void SetValue(TemplateContext context, SourceSpan span, object target, int index, object value)
+    public void SetValue(TemplateContext context, SourceSpan span, object target, int index, object? value)
     {
         throw new NotImplementedException();
     }
@@ -46,7 +46,7 @@ internal class WireMockListAccessor : IListAccessor, IObjectAccessor
         throw new NotImplementedException();
     }
 
-    public bool TrySetValue(TemplateContext context, SourceSpan span, object target, string member, object value)
+    public bool TrySetValue(TemplateContext context, SourceSpan span, object target, string member, object? value)
     {
         throw new NotImplementedException();
     }
@@ -56,7 +56,7 @@ internal class WireMockListAccessor : IListAccessor, IObjectAccessor
         throw new NotImplementedException();
     }
 
-    public bool TrySetItem(TemplateContext context, SourceSpan span, object target, object index, object value)
+    public bool TrySetItem(TemplateContext context, SourceSpan span, object target, object index, object? value)
     {
         throw new NotImplementedException();
     }

src/WireMock.Net.Minimal/Transformers/Scriban/WireMockTemplateContext.cs

@@ -8,9 +8,9 @@ namespace WireMock.Transformers.Scriban;
 
 internal class WireMockTemplateContext : TemplateContext
 {
-    protected override IObjectAccessor GetMemberAccessorImpl(object target)
+    protected override IObjectAccessor? GetMemberAccessorImpl(object target)
     {
-        return target?.GetType().GetGenericTypeDefinition() == typeof(WireMockList<>) ?
+        return target.GetType().GetGenericTypeDefinition() == typeof(WireMockList<>) ?
             new WireMockListAccessor() :
             base.GetMemberAccessorImpl(target);
     }

src/WireMock.Net.Minimal/WireMock.Net.Minimal.csproj

@@ -43,7 +43,7 @@
         <PackageReference Include="SimMetrics.Net" Version="1.0.5" />
         <PackageReference Include="TinyMapper.Signed" Version="4.0.0" />
         <PackageReference Include="Microsoft.IdentityModel.Protocols.OpenIdConnect" Version="6.34.0" />
-        <PackageReference Include="Scriban.Signed" Version="5.5.0" />
+        <PackageReference Include="Scriban.Signed" Version="7.0.6" />
     </ItemGroup>
 
     <ItemGroup>

src/WireMock.Net.NUnit/WireMock.Net.NUnit.csproj

@@ -25,7 +25,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.8.0" />
+        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.9.0" />
         <PackageReference Include="NUnit" Version="4.4.0" />
         <PackageReference Include="Stef.Validation" Version="0.2.0" />
     </ItemGroup>

src/WireMock.Net.OpenTelemetry/WireMock.Net.OpenTelemetry.csproj

@@ -25,9 +25,9 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.15.3" />
-        <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.15.2" />
-        <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.14.0" />
+        <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.15.3" />
     </ItemGroup>
 
     <ItemGroup>

src/WireMock.Net.RestClient/IWireMockAdminApi.cs

@@ -163,6 +163,22 @@ public interface IWireMockAdminApi
     [Header("Content-Type", "application/json")]
     Task<StatusModel> PutMappingAsync([Path] Guid guid, [Body] MappingModel mapping, CancellationToken cancellationToken = default);
 
+    /// <summary>
+    /// Enable a mapping based on the guid.
+    /// </summary>
+    /// <param name="guid">The Guid.</param>
+    /// <param name="cancellationToken">The optional cancellationToken.</param>
+    [Put("mappings/{guid}/enable")]
+    Task<StatusModel> EnableMappingAsync([Path] Guid guid, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Disable a mapping based on the guid.
+    /// </summary>
+    /// <param name="guid">The Guid.</param>
+    /// <param name="cancellationToken">The optional cancellationToken.</param>
+    [Put("mappings/{guid}/disable")]
+    Task<StatusModel> DisableMappingAsync([Path] Guid guid, CancellationToken cancellationToken = default);
+
     /// <summary>
     /// Delete a mapping based on the guid
     /// </summary>

src/WireMock.Net.RestClient/WireMock.Net.RestClient.csproj

@@ -33,7 +33,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.8.0" />
+        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.9.0" />
         <PackageReference Include="RestEase" Version="1.6.4" />
         <PackageReference Include="Stef.Validation" Version="0.2.0" />
     </ItemGroup>

src/WireMock.Net.Shared/Handlers/InMemoryScenarioStateStore.cs

@@ -0,0 +1,68 @@
+// Copyright © WireMock.Net
+
+using System.Collections.Concurrent;
+using System.Diagnostics.CodeAnalysis;
+
+namespace WireMock.Handlers;
+
+/// <summary>
+/// Provides an in-memory implementation of the <see cref="IScenarioStateStore" /> interface for managing scenario state objects by name.
+/// </summary>
+public class InMemoryScenarioStateStore : IScenarioStateStore
+{
+    private readonly ConcurrentDictionary<string, ScenarioState> _scenarios = new(StringComparer.OrdinalIgnoreCase);
+
+    /// <inheritdoc />
+    public bool TryGet(string name, [NotNullWhen(true)] out ScenarioState? state)
+    {
+        return _scenarios.TryGetValue(name, out state);
+    }
+
+    /// <inheritdoc />
+    public IReadOnlyList<ScenarioState> GetAll()
+    {
+        return _scenarios.Values.ToArray();
+    }
+
+    /// <inheritdoc />
+    public bool ContainsKey(string name)
+    {
+        return _scenarios.ContainsKey(name);
+    }
+
+    /// <inheritdoc />
+    public bool TryAdd(string name, ScenarioState scenarioState)
+    {
+        return _scenarios.TryAdd(name, scenarioState);
+    }
+
+    /// <inheritdoc />
+    public ScenarioState AddOrUpdate(string name, Func<string, ScenarioState> addFactory, Func<string, ScenarioState, ScenarioState> updateFactory)
+    {
+        return _scenarios.AddOrUpdate(name, addFactory, updateFactory);
+    }
+
+    /// <inheritdoc />
+    public ScenarioState? Update(string name, Action<ScenarioState> updateAction)
+    {
+        if (_scenarios.TryGetValue(name, out var state))
+        {
+            updateAction(state);
+            return state;
+        }
+
+        return null;
+    }
+
+    /// <inheritdoc />
+    public bool TryRemove(string name)
+    {
+        return _scenarios.TryRemove(name, out _);
+    }
+
+    /// <inheritdoc />
+    public void Clear()
+    {
+        _scenarios.Clear();
+    }
+}

src/WireMock.Net.Shared/IMapping.cs

@@ -108,6 +108,14 @@ public interface IMapping
     /// </value>
     bool IsProxy { get; }
 
+    /// <summary>
+    /// Gets a value indicating whether this mapping is disabled.
+    /// </summary>
+    /// <value>
+    /// <c>true</c> if this mapping is disabled; otherwise, <c>false</c>.
+    /// </value>
+    bool IsDisabled { get; set; }
+
     /// <summary>
     /// Gets a value indicating whether this mapping to be logged.
     /// </summary>
@@ -135,7 +143,7 @@ public interface IMapping
     /// </summary>
     object? Data { get; }
 
-    /// <summary> 
+    /// <summary>
     /// The probability when this request should be matched. Value is between 0 and 1. [Optional]
     /// </summary>
     double? Probability { get; }

src/WireMock.Net.Shared/Matchers/MatchResult.cs

@@ -1,6 +1,5 @@
 // Copyright © WireMock.Net
 
-using System.Linq;
 using Stef.Validation;
 using WireMock.Extensions;
 using WireMock.Matchers.Request;
@@ -119,7 +118,7 @@ public class MatchResult
         return new MatchDetail
         {
             Name = Name,
-            MatcherType = typeof(MatchResult),
+            MatcherType = typeof(MatchResult).Name,
             Score = Score,
             Exception = Exception,
             MatchDetails = MatchResults?.Select(mr => mr.ToMatchDetail()).ToArray()

src/WireMock.Net.Shared/Settings/WireMockServerSettings.cs

@@ -175,6 +175,17 @@ public class WireMockServerSettings
     [JsonIgnore]
     public IFileSystemHandler FileSystemHandler { get; set; } = null!;
 
+    /// <summary>
+    /// Gets or sets the store used to persist scenario state information.
+    /// </summary>
+    /// <remarks>
+    /// The scenario state store manages the storage and retrieval of state data associated with scenarios.
+    /// By default, an in-memory implementation is used, but this property can be set to a custom implementation to support alternative storage mechanisms such as databases or distributed caches.
+    /// </remarks>
+    [PublicAPI]
+    [JsonIgnore]
+    public IScenarioStateStore ScenarioStateStore { get; set; } = new InMemoryScenarioStateStore();
+
     /// <summary>
     /// Action which can be used to add additional Handlebars registrations. [Optional]
     /// </summary>
@@ -254,7 +265,7 @@ public class WireMockServerSettings
     /// Whether to accept any client certificate
     /// </summary>
     public bool AcceptAnyClientCertificate { get; set; }
-    
+
     /// <summary>
     /// Defines the global IWebhookSettings to use.
     /// </summary>

src/WireMock.Net.Shared/WireMock.Net.Shared.csproj

@@ -30,7 +30,7 @@
         <PackageReference Include="Stef.Validation" Version="0.2.0" />
         <PackageReference Include="AnyOf" Version="0.5.0.1" />
         <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.2" />
-        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.8.0" />
+        <PackageReference Include="JsonConverter.Newtonsoft.Json" Version="0.9.0" />
     </ItemGroup>
 
     <ItemGroup>

src/dotnet-WireMock.Net/Json/SourceGenerationContext.cs

@@ -1,6 +1,7 @@
 // Copyright © WireMock.Net
 
 using System.Text.Json.Serialization;
+using Newtonsoft.Json.Linq;
 using WireMock.Admin.Mappings;
 using WireMock.Admin.Requests;
 using WireMock.Types;
@@ -9,10 +10,13 @@ namespace WireMock.Net.Json;
 
 [JsonSourceGenerationOptions(WriteIndented = true)]
 [JsonSerializable(typeof(EncodingModel))]
+[JsonSerializable(typeof(JArray))]
+[JsonSerializable(typeof(JObject))]
 [JsonSerializable(typeof(LogEntryModel))]
 [JsonSerializable(typeof(LogRequestModel))]
 [JsonSerializable(typeof(LogResponseModel))]
 [JsonSerializable(typeof(LogRequestMatchModel))]
+[JsonSerializable(typeof(StatusModel))]
 [JsonSerializable(typeof(WireMockList<string>))]
 internal partial class SourceGenerationContext : JsonSerializerContext
 {

src/dotnet-WireMock.Net/WireMockLogger.cs

@@ -1,6 +1,5 @@
 // Copyright © WireMock.Net
 
-using System;
 using System.Text.Json;
 using Microsoft.Extensions.Logging;
 using WireMock.Admin.Requests;
@@ -11,11 +10,6 @@ namespace WireMock.Net;
 
 public class WireMockLogger : IWireMockLogger
 {
-    private readonly JsonSerializerOptions _options = new()
-    {
-        WriteIndented = true
-    };
-
     private readonly ILogger _logger;
 
     public WireMockLogger(ILogger logger)

test/WireMock.Net.Tests.UsingNuGet/WireMock.Net.Tests.UsingNuGet.csproj

@@ -11,12 +11,12 @@
 
     <ItemGroup>
         <PackageReference Include="AwesomeAssertions" Version="9.4.0" />
-        <PackageReference Include="coverlet.collector" Version="6.0.4">
+        <PackageReference Include="coverlet.collector" Version="8.0.1">
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
-        <PackageReference Include="WireMock.Net" Version="1.25.0" />
+        <PackageReference Include="WireMock.Net" Version="2.1.0" />
         <PackageReference Include="xunit.v3" Version="3.2.2" />
         <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
             <PrivateAssets>all</PrivateAssets>

test/WireMock.Net.Tests/AdminApi/WireMockAdminApiTests.IsDisabled.cs

@@ -0,0 +1,134 @@
+// Copyright © WireMock.Net
+
+using RestEase;
+using WireMock.Admin.Mappings;
+using WireMock.Client;
+using WireMock.Server;
+
+namespace WireMock.Net.Tests.AdminApi;
+
+public partial class WireMockAdminApiTests
+{
+    [Fact]
+    public async Task IWireMockAdminApi_PostMappingAsync_WithIsDisabledTrue_DoesNotMatchRequests()
+    {
+        // Arrange
+        var ct = TestContext.Current.CancellationToken;
+        using var server = WireMockServer.StartWithAdminInterface();
+        var api = RestClient.For<IWireMockAdminApi>(server.Urls[0]);
+        var httpClient = server.CreateClient();
+
+        var model = new MappingModel
+        {
+            Request = new RequestModel { Path = "/foo", Methods = ["GET"] },
+            Response = new ResponseModel { Body = "hello", StatusCode = 200 },
+            IsDisabled = true
+        };
+
+        // Act — POST the disabled mapping
+        var postResult = await api.PostMappingAsync(model, ct);
+        postResult.Should().NotBeNull();
+
+        // Assert — request should not be matched (404)
+        var response = await httpClient.GetAsync("/foo", ct);
+        ((int)response.StatusCode).Should().Be(404);
+
+        // Assert — mapping exists but IsDisabled is true
+        server.Mappings.Where(m => !m.IsAdminInterface).Should().ContainSingle(m => m.IsDisabled == true);
+    }
+
+    [Fact]
+    public async Task IWireMockAdminApi_DisableMappingAsync_PreventsMatching()
+    {
+        // Arrange
+        var ct = TestContext.Current.CancellationToken;
+        using var server = WireMockServer.StartWithAdminInterface();
+        var api = RestClient.For<IWireMockAdminApi>(server.Urls[0]);
+        var httpClient = server.CreateClient();
+
+        var model = new MappingModel
+        {
+            Request = new RequestModel { Path = "/bar", Methods = ["GET"] },
+            Response = new ResponseModel { Body = "world", StatusCode = 200 }
+        };
+        var postResult = await api.PostMappingAsync(model, ct);
+        var guid = postResult.Guid!.Value;
+
+        // Assert — mapping matches before disable
+        var before = await httpClient.GetAsync("/bar", ct);
+        ((int)before.StatusCode).Should().Be(200);
+
+        // Act — disable
+        var disableResult = await api.DisableMappingAsync(guid, ct);
+        disableResult.Status.Should().Be("Mapping disabled");
+
+        // Assert — no match after disable
+        var after = await httpClient.GetAsync("/bar", ct);
+        ((int)after.StatusCode).Should().Be(404);
+    }
+
+    [Fact]
+    public async Task IWireMockAdminApi_EnableMappingAsync_ResumesMatching()
+    {
+        // Arrange
+        var ct = TestContext.Current.CancellationToken;
+        using var server = WireMockServer.StartWithAdminInterface();
+        var api = RestClient.For<IWireMockAdminApi>(server.Urls[0]);
+        var httpClient = server.CreateClient();
+
+        var model = new MappingModel
+        {
+            Request = new RequestModel { Path = "/baz", Methods = ["GET"] },
+            Response = new ResponseModel { Body = "re-enabled", StatusCode = 200 },
+            IsDisabled = true
+        };
+        var postResult = await api.PostMappingAsync(model, ct);
+        var guid = postResult.Guid!.Value;
+
+        // Assert — no match while disabled
+        var before = await httpClient.GetAsync("/baz", ct);
+        ((int)before.StatusCode).Should().Be(404);
+
+        // Act — enable
+        var enableResult = await api.EnableMappingAsync(guid, ct);
+        enableResult.Status.Should().Be("Mapping enabled");
+
+        // Assert — mapping matches after enable
+        var after = await httpClient.GetAsync("/baz", ct);
+        ((int)after.StatusCode).Should().Be(200);
+    }
+
+    [Fact]
+    public async Task IWireMockAdminApi_GetMappingAsync_ReturnsIsDisabledTrue_WhenDisabled()
+    {
+        // Arrange
+        var ct = TestContext.Current.CancellationToken;
+        using var server = WireMockServer.StartWithAdminInterface();
+        var api = RestClient.For<IWireMockAdminApi>(server.Urls[0]);
+
+        var disabledModel = new MappingModel
+        {
+            Request = new RequestModel { Path = "/check-disabled" },
+            Response = new ResponseModel { Body = "x", StatusCode = 200 },
+            IsDisabled = true
+        };
+        var enabledModel = new MappingModel
+        {
+            Request = new RequestModel { Path = "/check-enabled" },
+            Response = new ResponseModel { Body = "y", StatusCode = 200 }
+        };
+
+        var disabledPost = await api.PostMappingAsync(disabledModel, ct);
+        var enabledPost = await api.PostMappingAsync(enabledModel, ct);
+
+        // Act
+        var disabledGot = await api.GetMappingAsync(disabledPost.Guid!.Value, ct);
+        var enabledGot = await api.GetMappingAsync(enabledPost.Guid!.Value, ct);
+
+        // Assert — disabled mapping serializes IsDisabled = true
+        disabledGot.IsDisabled.Should().BeTrue();
+
+        // Assert — enabled mapping omits IsDisabled (null = default not disabled)
+        enabledGot.IsDisabled.Should().BeNull();
+    }
+}

test/WireMock.Net.Tests/Constants.cs

@@ -6,5 +6,5 @@ internal static class Constants
 {
     internal const int NumStaticMappings = 10;
 
-    internal const int NumAdminMappings = 37;
+    internal const int NumAdminMappings = 39;
 }

test/WireMock.Net.Tests/Handlers/FileBasedScenarioStateStoreTests.cs

@@ -0,0 +1,273 @@
+// Copyright © WireMock.Net
+
+using System;
+using System.IO;
+using Newtonsoft.Json;
+using WireMock.Handlers;
+using Xunit;
+
+namespace WireMock.Net.Tests.Handlers;
+
+public class FileBasedScenarioStateStoreTests : IDisposable
+{
+    private readonly string _tempFolder;
+    private readonly string _scenariosFolder;
+
+    public FileBasedScenarioStateStoreTests()
+    {
+        _tempFolder = Path.Combine(Path.GetTempPath(), "WireMock_Tests_" + Guid.NewGuid().ToString("N"));
+        _scenariosFolder = Path.Combine(_tempFolder, "__admin", "scenarios");
+    }
+
+    public void Dispose()
+    {
+        if (Directory.Exists(_tempFolder))
+        {
+            Directory.Delete(_tempFolder, true);
+        }
+    }
+
+    private FileBasedScenarioStateStore CreateSut() => new(_tempFolder);
+
+    // --- Mirror tests from InMemoryScenarioStateStoreTests ---
+
+    [Fact]
+    public void TryAdd_ShouldAddNewScenario()
+    {
+        var sut = CreateSut();
+        var state = new ScenarioState { Name = "scenario1" };
+
+        sut.TryAdd("scenario1", state).Should().BeTrue();
+
+        sut.ContainsKey("scenario1").Should().BeTrue();
+    }
+
+    [Fact]
+    public void TryAdd_ShouldReturnFalse_WhenScenarioAlreadyExists()
+    {
+        var sut = CreateSut();
+        var state = new ScenarioState { Name = "scenario1" };
+        sut.TryAdd("scenario1", state);
+
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" }).Should().BeFalse();
+    }
+
+    [Fact]
+    public void TryGet_ShouldReturnTrue_WhenExists()
+    {
+        var sut = CreateSut();
+        var state = new ScenarioState { Name = "scenario1", NextState = "state2" };
+        sut.TryAdd("scenario1", state);
+
+        sut.TryGet("scenario1", out var result).Should().BeTrue();
+
+        result.Should().NotBeNull();
+        result!.NextState.Should().Be("state2");
+    }
+
+    [Fact]
+    public void TryGet_ShouldReturnFalse_WhenNotExists()
+    {
+        var sut = CreateSut();
+        sut.TryGet("nonexistent", out var result).Should().BeFalse();
+        result.Should().BeNull();
+    }
+
+    [Fact]
+    public void GetAll_ShouldReturnAllScenarios()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+        sut.TryAdd("scenario2", new ScenarioState { Name = "scenario2" });
+
+        var result = sut.GetAll();
+
+        result.Should().HaveCount(2);
+    }
+
+    [Fact]
+    public void GetAll_ShouldReturnEmpty_WhenNoScenarios()
+    {
+        var sut = CreateSut();
+        sut.GetAll().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void Update_ShouldModifyExistingScenario()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", Counter = 0 });
+
+        var result = sut.Update("scenario1", s => { s.Counter = 5; s.NextState = "state2"; });
+
+        result.Should().NotBeNull();
+        result!.Counter.Should().Be(5);
+        result.NextState.Should().Be("state2");
+    }
+
+    [Fact]
+    public void Update_ShouldReturnNull_WhenNotExists()
+    {
+        var sut = CreateSut();
+        sut.Update("nonexistent", s => { s.Counter = 5; }).Should().BeNull();
+    }
+
+    [Fact]
+    public void AddOrUpdate_ShouldAddNewScenario()
+    {
+        var sut = CreateSut();
+        var result = sut.AddOrUpdate(
+            "scenario1",
+            _ => new ScenarioState { Name = "scenario1", NextState = "added" },
+            (_, current) => { current.NextState = "updated"; return current; }
+        );
+
+        result.NextState.Should().Be("added");
+    }
+
+    [Fact]
+    public void AddOrUpdate_ShouldUpdateExistingScenario()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", NextState = "initial" });
+
+        var result = sut.AddOrUpdate(
+            "scenario1",
+            _ => new ScenarioState { Name = "scenario1", NextState = "added" },
+            (_, current) => { current.NextState = "updated"; return current; }
+        );
+
+        result.NextState.Should().Be("updated");
+    }
+
+    [Fact]
+    public void TryRemove_ShouldRemoveExistingScenario()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+
+        sut.TryRemove("scenario1").Should().BeTrue();
+        sut.ContainsKey("scenario1").Should().BeFalse();
+    }
+
+    [Fact]
+    public void TryRemove_ShouldReturnFalse_WhenNotExists()
+    {
+        var sut = CreateSut();
+        sut.TryRemove("nonexistent").Should().BeFalse();
+    }
+
+    [Fact]
+    public void Clear_ShouldRemoveAllScenarios()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+        sut.TryAdd("scenario2", new ScenarioState { Name = "scenario2" });
+
+        sut.Clear();
+
+        sut.GetAll().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void ContainsKey_ShouldBeCaseInsensitive()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("Scenario1", new ScenarioState { Name = "Scenario1" });
+
+        sut.ContainsKey("scenario1").Should().BeTrue();
+        sut.ContainsKey("SCENARIO1").Should().BeTrue();
+    }
+
+    [Fact]
+    public void TryGet_ShouldBeCaseInsensitive()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("Scenario1", new ScenarioState { Name = "Scenario1", NextState = "state2" });
+
+        sut.TryGet("scenario1", out var result1).Should().BeTrue();
+        result1!.NextState.Should().Be("state2");
+
+        sut.TryGet("SCENARIO1", out var result2).Should().BeTrue();
+        result2!.NextState.Should().Be("state2");
+    }
+
+    // --- File-persistence-specific tests ---
+
+    [Fact]
+    public void TryAdd_ShouldCreateJsonFileOnDisk()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", NextState = "state2" });
+
+        var filePath = Path.Combine(_scenariosFolder, "scenario1.json");
+        File.Exists(filePath).Should().BeTrue();
+
+        var json = File.ReadAllText(filePath);
+        var deserialized = JsonConvert.DeserializeObject<ScenarioState>(json);
+        deserialized!.Name.Should().Be("scenario1");
+        deserialized.NextState.Should().Be("state2");
+    }
+
+    [Fact]
+    public void TryRemove_ShouldDeleteJsonFileFromDisk()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+
+        var filePath = Path.Combine(_scenariosFolder, "scenario1.json");
+        File.Exists(filePath).Should().BeTrue();
+
+        sut.TryRemove("scenario1");
+
+        File.Exists(filePath).Should().BeFalse();
+    }
+
+    [Fact]
+    public void Clear_ShouldDeleteAllJsonFilesFromDisk()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+        sut.TryAdd("scenario2", new ScenarioState { Name = "scenario2" });
+
+        Directory.GetFiles(_scenariosFolder, "*.json").Should().HaveCount(2);
+
+        sut.Clear();
+
+        Directory.GetFiles(_scenariosFolder, "*.json").Should().BeEmpty();
+    }
+
+    [Fact]
+    public void Constructor_ShouldLoadExistingScenariosFromDisk()
+    {
+        // Pre-write JSON files before constructing the store
+        Directory.CreateDirectory(_scenariosFolder);
+        var state1 = new ScenarioState { Name = "scenario1", NextState = "loaded1" };
+        var state2 = new ScenarioState { Name = "scenario2", NextState = "loaded2", Counter = 3 };
+        File.WriteAllText(Path.Combine(_scenariosFolder, "scenario1.json"), JsonConvert.SerializeObject(state1));
+        File.WriteAllText(Path.Combine(_scenariosFolder, "scenario2.json"), JsonConvert.SerializeObject(state2));
+
+        var sut = CreateSut();
+
+        sut.GetAll().Should().HaveCount(2);
+        sut.TryGet("scenario1", out var loaded1).Should().BeTrue();
+        loaded1!.NextState.Should().Be("loaded1");
+        sut.TryGet("scenario2", out var loaded2).Should().BeTrue();
+        loaded2!.Counter.Should().Be(3);
+    }
+
+    [Fact]
+    public void Update_ShouldPersistChangesToDisk()
+    {
+        var sut = CreateSut();
+        sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", Counter = 0 });
+
+        sut.Update("scenario1", s => { s.Counter = 10; s.NextState = "persisted"; });
+
+        var filePath = Path.Combine(_scenariosFolder, "scenario1.json");
+        var json = File.ReadAllText(filePath);
+        var deserialized = JsonConvert.DeserializeObject<ScenarioState>(json);
+        deserialized!.Counter.Should().Be(10);
+        deserialized.NextState.Should().Be("persisted");
+    }
+}

test/WireMock.Net.Tests/Handlers/InMemoryScenarioStateStoreTests.cs

@@ -0,0 +1,157 @@
+// Copyright © WireMock.Net
+
+using WireMock.Handlers;
+using Xunit;
+
+namespace WireMock.Net.Tests.Handlers;
+
+public class InMemoryScenarioStateStoreTests
+{
+    private readonly InMemoryScenarioStateStore _sut = new();
+
+    [Fact]
+    public void TryAdd_ShouldAddNewScenario()
+    {
+        var state = new ScenarioState { Name = "scenario1" };
+
+        _sut.TryAdd("scenario1", state).Should().BeTrue();
+
+        _sut.ContainsKey("scenario1").Should().BeTrue();
+    }
+
+    [Fact]
+    public void TryAdd_ShouldReturnFalse_WhenScenarioAlreadyExists()
+    {
+        var state = new ScenarioState { Name = "scenario1" };
+        _sut.TryAdd("scenario1", state);
+
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" }).Should().BeFalse();
+    }
+
+    [Fact]
+    public void TryGet_ShouldReturnTrue_WhenExists()
+    {
+        var state = new ScenarioState { Name = "scenario1", NextState = "state2" };
+        _sut.TryAdd("scenario1", state);
+
+        _sut.TryGet("scenario1", out var result).Should().BeTrue();
+
+        result.Should().NotBeNull();
+        result!.NextState.Should().Be("state2");
+    }
+
+    [Fact]
+    public void TryGet_ShouldReturnFalse_WhenNotExists()
+    {
+        _sut.TryGet("nonexistent", out var result).Should().BeFalse();
+        result.Should().BeNull();
+    }
+
+    [Fact]
+    public void GetAll_ShouldReturnAllScenarios()
+    {
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+        _sut.TryAdd("scenario2", new ScenarioState { Name = "scenario2" });
+
+        var result = _sut.GetAll();
+
+        result.Should().HaveCount(2);
+    }
+
+    [Fact]
+    public void GetAll_ShouldReturnEmpty_WhenNoScenarios()
+    {
+        _sut.GetAll().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void Update_ShouldModifyExistingScenario()
+    {
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", Counter = 0 });
+
+        var result = _sut.Update("scenario1", s => { s.Counter = 5; s.NextState = "state2"; });
+
+        result.Should().NotBeNull();
+        result!.Counter.Should().Be(5);
+        result.NextState.Should().Be("state2");
+    }
+
+    [Fact]
+    public void Update_ShouldReturnNull_WhenNotExists()
+    {
+        _sut.Update("nonexistent", s => { s.Counter = 5; }).Should().BeNull();
+    }
+
+    [Fact]
+    public void AddOrUpdate_ShouldAddNewScenario()
+    {
+        var result = _sut.AddOrUpdate(
+            "scenario1",
+            _ => new ScenarioState { Name = "scenario1", NextState = "added" },
+            (_, current) => { current.NextState = "updated"; return current; }
+        );
+
+        result.NextState.Should().Be("added");
+    }
+
+    [Fact]
+    public void AddOrUpdate_ShouldUpdateExistingScenario()
+    {
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1", NextState = "initial" });
+
+        var result = _sut.AddOrUpdate(
+            "scenario1",
+            _ => new ScenarioState { Name = "scenario1", NextState = "added" },
+            (_, current) => { current.NextState = "updated"; return current; }
+        );
+
+        result.NextState.Should().Be("updated");
+    }
+
+    [Fact]
+    public void TryRemove_ShouldRemoveExistingScenario()
+    {
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+
+        _sut.TryRemove("scenario1").Should().BeTrue();
+        _sut.ContainsKey("scenario1").Should().BeFalse();
+    }
+
+    [Fact]
+    public void TryRemove_ShouldReturnFalse_WhenNotExists()
+    {
+        _sut.TryRemove("nonexistent").Should().BeFalse();
+    }
+
+    [Fact]
+    public void Clear_ShouldRemoveAllScenarios()
+    {
+        _sut.TryAdd("scenario1", new ScenarioState { Name = "scenario1" });
+        _sut.TryAdd("scenario2", new ScenarioState { Name = "scenario2" });
+
+        _sut.Clear();
+
+        _sut.GetAll().Should().BeEmpty();
+    }
+
+    [Fact]
+    public void ContainsKey_ShouldBeCaseInsensitive()
+    {
+        _sut.TryAdd("Scenario1", new ScenarioState { Name = "Scenario1" });
+
+        _sut.ContainsKey("scenario1").Should().BeTrue();
+        _sut.ContainsKey("SCENARIO1").Should().BeTrue();
+    }
+
+    [Fact]
+    public void TryGet_ShouldBeCaseInsensitive()
+    {
+        _sut.TryAdd("Scenario1", new ScenarioState { Name = "Scenario1", NextState = "state2" });
+
+        _sut.TryGet("scenario1", out var result1).Should().BeTrue();
+        result1!.NextState.Should().Be("state2");
+
+        _sut.TryGet("SCENARIO1", out var result2).Should().BeTrue();
+        result2!.NextState.Should().Be("state2");
+    }
+}

test/WireMock.Net.Tests/Http/HttpRequestMessageHelperTests.cs

@@ -27,7 +27,7 @@ public class HttpRequestMessageHelperTests
         var message = HttpRequestMessageHelper.Create(request, "http://url");
 
         // Assert
-        message.Headers.GetValues("x").Should().Equal(new[] { "value-1" });
+        message.Headers.GetValues("x").Should().Equal(["value-1"]);
     }
 
     [Fact]
@@ -101,7 +101,7 @@ public class HttpRequestMessageHelperTests
 
         // Assert
         (await message.Content!.ReadAsStringAsync(_ct)).Should().Be("{\"x\":42}");
-        message.Content.Headers.GetValues("Content-Type").Should().Equal(new[] { "application/json" });
+        message.Content.Headers.GetValues("Content-Type").Should().Equal(["application/json"]);
     }
 
     [Fact]
@@ -121,7 +121,7 @@ public class HttpRequestMessageHelperTests
 
         // Assert
         (await message.Content!.ReadAsStringAsync(_ct)).Should().Be("{\"x\":42}");
-        message.Content.Headers.GetValues("Content-Type").Should().Equal(new[] { "application/json; charset=utf-8" });
+        message.Content.Headers.GetValues("Content-Type").Should().Equal(["application/json; charset=utf-8"]);
     }
 
     [Fact]
@@ -142,7 +142,7 @@ public class HttpRequestMessageHelperTests
 
         // Assert
         (await message.Content!.ReadAsStringAsync(_ct)).Should().Be("{\"x\":42}");
-        message.Content.Headers.GetValues("Content-Type").Should().Equal(new[] { "multipart/form-data" });
+        message.Content.Headers.GetValues("Content-Type").Should().Equal(["multipart/form-data"]);
     }
 
 
@@ -162,7 +162,7 @@ public class HttpRequestMessageHelperTests
         var message = HttpRequestMessageHelper.Create(request, "http://url");
 
         // Assert
-        message.Content!.Headers.GetValues("Content-Type").Should().Equal(new[] { "application/xml" });
+        message.Content!.Headers.GetValues("Content-Type").Should().Equal(["application/xml"]);
     }
 
     [Fact]
@@ -181,7 +181,7 @@ public class HttpRequestMessageHelperTests
         var message = HttpRequestMessageHelper.Create(request, "http://url");
 
         // Assert
-        message.Content!.Headers.GetValues("Content-Type").Should().Equal(new[] { "application/xml; charset=UTF-8" });
+        message.Content!.Headers.GetValues("Content-Type").Should().Equal(["application/xml; charset=UTF-8"]);
     }
 
     [Fact]
@@ -200,7 +200,7 @@ public class HttpRequestMessageHelperTests
         var message = HttpRequestMessageHelper.Create(request, "http://url");
 
         // Assert
-        message.Content!.Headers.GetValues("Content-Type").Should().Equal(new[] { "application/xml; charset=Ascii" });
+        message.Content!.Headers.GetValues("Content-Type").Should().Equal(["application/xml; charset=Ascii"]);
     }
 
     [Fact]
@@ -242,7 +242,7 @@ public class HttpRequestMessageHelperTests
 
         // Assert
         (await message.Content!.ReadAsStringAsync(_ct)).Should().Be(body);
-        message.Content.Headers.GetValues("Content-Type").Should().Equal(new[] { "multipart/form-data" });
+        message.Content.Headers.GetValues("Content-Type").Should().Equal(["multipart/form-data"]);
     }
 
     [Theory]
@@ -269,7 +269,4 @@ public class HttpRequestMessageHelperTests
         // Assert
         message.Content?.Headers.ContentLength.Should().Be(resultShouldBe ? value : null);
     }
-}
+}
-
-
-

test/WireMock.Net.Tests/Owin/Mappers/OwinResponseMapperTests.cs

@@ -9,6 +9,8 @@ using WireMock.Util;
 using WireMock.Owin;
 using Microsoft.AspNetCore.Http;
 using Microsoft.Extensions.Primitives;
+using JsonConverter.Newtonsoft.Json;
+using JsonConverter.System.Text.Json;
 
 namespace WireMock.Net.Tests.Owin.Mappers;
 
@@ -34,6 +36,7 @@ public class OwinResponseMapperTests
         _optionsMock = new Mock<IWireMockMiddlewareOptions>();
         _optionsMock.SetupAllProperties();
         _optionsMock.SetupGet(o => o.FileSystemHandler).Returns(_fileSystemHandlerMock.Object);
+        _optionsMock.SetupGet(o => o.DefaultJsonSerializer).Returns(new NewtonsoftJsonConverter());
 
         _headers = new Mock<IHeaderDictionary>();
         _headers.SetupAllProperties();
@@ -186,7 +189,7 @@ public class OwinResponseMapperTests
     }
 
     [Fact]
-    public async Task OwinResponseMapper_MapAsync_BodyAsJson()
+    public async Task OwinResponseMapper_MapAsync_BodyAsJson_UsingNewtonsoftJson()
     {
         // Arrange
         var json = new { t = "x", i = (string?)null };
@@ -203,6 +206,25 @@ public class OwinResponseMapperTests
         _stream.Verify(s => s.WriteAsync(new byte[] { 123, 34, 116, 34, 58, 34, 120, 34, 125 }, 0, 9, It.IsAny<CancellationToken>()), Times.Once);
     }
 
+    [Fact]
+    public async Task OwinResponseMapper_MapAsync_BodyAsJson_UsingSystemTextJson()
+    {
+        // Arrange
+        var json = new { t = "x", i = (string?)null };
+        var responseMessage = new ResponseMessage
+        {
+            Headers = new Dictionary<string, WireMockList<string>>(),
+            BodyData = new BodyData { DetectedBodyType = BodyType.Json, BodyAsJson = json, BodyAsJsonIndented = false }
+        };
+        _optionsMock.SetupGet(o => o.DefaultJsonSerializer).Returns(new SystemTextJsonConverter());
+
+        // Act
+        await _sut.MapAsync(responseMessage, _responseMock.Object);
+
+        // Assert
+        _stream.Verify(s => s.WriteAsync(new byte[] { 123, 34, 116, 34, 58, 34, 120, 34, 125 }, 0, 9, It.IsAny<CancellationToken>()), Times.Once);
+    }
+
     [Fact]
     public async Task OwinResponseMapper_MapAsync_SetResponseHeaders()
     {

test/WireMock.Net.Tests/Owin/MappingMatcherTests.cs

@@ -2,6 +2,7 @@
 
 using System.Collections.Concurrent;
 using Moq;
+using WireMock.Handlers;
 using WireMock.Logging;
 using WireMock.Matchers.Request;
 using WireMock.Models;
@@ -23,7 +24,7 @@ public class MappingMatcherTests
         _optionsMock.SetupAllProperties();
         _optionsMock.Setup(o => o.Mappings).Returns(new ConcurrentDictionary<Guid, IMapping>());
         _optionsMock.Setup(o => o.LogEntries).Returns([]);
-        _optionsMock.Setup(o => o.Scenarios).Returns(new ConcurrentDictionary<string, ScenarioState>());
+        _optionsMock.Setup(o => o.ScenarioStateStore).Returns(new InMemoryScenarioStateStore());
 
         var loggerMock = new Mock<IWireMockLogger>();
         loggerMock.SetupAllProperties();
@@ -55,6 +56,7 @@ public class MappingMatcherTests
     {
         // Assign
         var mappingMock = new Mock<IMapping>();
+        mappingMock.SetupGet(m => m.IsDisabled).Returns(false);
         mappingMock.Setup(m => m.GetRequestMatchResult(It.IsAny<RequestMessage>(), It.IsAny<string>())).Throws<Exception>();
 
         var mappings = new ConcurrentDictionary<Guid, IMapping>();
@@ -228,6 +230,35 @@ public class MappingMatcherTests
         result.Match!.Mapping.Guid.Should().Be(withProbability);
     }
 
+    [Fact]
+    public void MappingMatcher_FindBestMatch_WhenMappingIsDisabled_ShouldReturnNull()
+    {
+        // Assign
+        var guid = Guid.Parse("00000000-0000-0000-0000-000000000001");
+        var mappingMock = new Mock<IMapping>();
+        mappingMock.SetupGet(m => m.Guid).Returns(guid);
+        mappingMock.SetupGet(m => m.IsDisabled).Returns(true);
+        mappingMock.SetupGet(m => m.Probability).Returns((double?)null);
+
+        var matchResult = new RequestMatchResult();
+        matchResult.AddScore(typeof(object), 1.0, null);
+        mappingMock.Setup(m => m.GetRequestMatchResult(It.IsAny<RequestMessage>(), It.IsAny<string>())).Returns(matchResult);
+
+        var mappings = new ConcurrentDictionary<Guid, IMapping>();
+        mappings.TryAdd(guid, mappingMock.Object);
+        _optionsMock.Setup(o => o.Mappings).Returns(mappings);
+
+        var request = new RequestMessage(new UrlDetails("http://localhost/foo"), "GET", "::1");
+
+        // Act
+        var result = _sut.FindBestMatch(request);
+
+        // Assert
+        result.Match.Should().BeNull();
+        result.Partial.Should().BeNull();
+        mappingMock.Verify(m => m.GetRequestMatchResult(It.IsAny<RequestMessage>(), It.IsAny<string>()), Times.Never);
+    }
+
     private static ConcurrentDictionary<Guid, IMapping> InitMappings(params (Guid guid, double[] scores, double? probability)[] matches)
     {
         var mappings = new ConcurrentDictionary<Guid, IMapping>();
@@ -236,6 +267,7 @@ public class MappingMatcherTests
         {
             var mappingMock = new Mock<IMapping>();
             mappingMock.SetupGet(m => m.Guid).Returns(match.guid);
+            mappingMock.SetupGet(m => m.IsDisabled).Returns(false);
 
             var requestMatchResult = new RequestMatchResult();
             foreach (var score in match.scores)

test/WireMock.Net.Tests/Owin/WireMockMiddlewareTests.cs

@@ -55,7 +55,7 @@ public class WireMockMiddlewareTests
         _optionsMock.SetupAllProperties();
         _optionsMock.Setup(o => o.Mappings).Returns(_mappings);
         _optionsMock.Setup(o => o.LogEntries).Returns(new ConcurrentObservableCollection<LogEntry>());
-        _optionsMock.Setup(o => o.Scenarios).Returns(new ConcurrentDictionary<string, ScenarioState>());
+        _optionsMock.Setup(o => o.ScenarioStateStore).Returns(new InMemoryScenarioStateStore());
         _optionsMock.Setup(o => o.Logger.Warn(It.IsAny<string>(), It.IsAny<object[]>()));
         _optionsMock.Setup(o => o.Logger.Error(It.IsAny<string>(), It.IsAny<object[]>()));
         _optionsMock.Setup(o => o.Logger.DebugRequestResponse(It.IsAny<LogEntryModel>(), It.IsAny<bool>()));

test/WireMock.Net.Tests/Serialization/MappingSerializerTests.cs

@@ -3,6 +3,8 @@
 using JsonConverter.Newtonsoft.Json;
 using WireMock.Admin.Mappings;
 using WireMock.Serialization;
+using Newtonsoft.Json.Linq;
+
 #if NET8_0_OR_GREATER
 using JsonConverter.System.Text.Json;
 #endif
@@ -319,5 +321,92 @@ public class MappingSerializerTests
         act.Should().Throw<InvalidOperationException>()
             .WithMessage("Cannot deserialize the provided value to an array or object.");
     }
+
+    [Fact]
+    public void MappingSerializer_DeserializeJsonToArray_WithNewtonsoftJson_DateTimeStringInQueryParamExactMatcherPattern_ShouldPreservePatternAsString()
+    {
+        // Arrange
+        var jsonConverter = new NewtonsoftJsonConverter();
+        var serializer = new MappingSerializer(jsonConverter);
+        var mappingJson =
+            """
+            {
+                "Guid": "12345678-1234-1234-1234-aaaaaaaaaaaa",
+                "Request": {
+                    "Path": "/api/report",
+                    "Methods": ["GET"],
+                    "Params": [
+                        {
+                            "Name": "asOfDate",
+                            "Matchers": [
+                                {
+                                    "Name": "ExactMatcher",
+                                    "Pattern": "2021-11-10T13:39:13.705"
+                                }
+                            ]
+                        }
+                    ]
+                },
+                "Response": {
+                    "StatusCode": 200
+                }
+            }
+            """;
+
+        // Act
+        var result = serializer.DeserializeJsonToArray<MappingModel>(mappingJson);
+
+        // Assert
+        result.Should().HaveCount(1);
+        var matcher = result[0].Request!.Params![0].Matchers![0];
+        matcher.Name.Should().Be("ExactMatcher");
+        matcher.Pattern.Should().BeOfType<string>()
+            .Which.Should().Be("2021-11-10T13:39:13.705",
+                "datetime-format strings in ExactMatcher Pattern fields must survive deserialization as strings, " +
+                "not be auto-converted to DateTime by Newtonsoft.Json's DateParseHandling.DateTime");
+    }
+
+    [Fact]
+    public void MappingSerializer_DeserializeJsonToArray_WithNewtonsoftJson_DateTimeStringInJsonMatcherBodyPattern_ShouldPreservePatternAsString()
+    {
+        // Arrange
+        var jsonConverter = new NewtonsoftJsonConverter();
+        var serializer = new MappingSerializer(jsonConverter);
+        // Pattern is an INLINE JSON object (not a string) - this is how WireMock mapping files store
+        // JsonMatcher patterns when recorded. Newtonsoft with DateParseHandling.DateTime will convert
+        // the datetime value inside the JObject to JTokenType.Date during deserialization.
+        var mappingJson =
+            """
+            {
+                "Guid": "12345678-1234-1234-1234-bbbbbbbbbbbb",
+                "Request": {
+                    "Path": "/api/report",
+                    "Methods": ["POST"],
+                    "Body": {
+                        "Matcher": {
+                            "Name": "JsonMatcher",
+                            "Pattern": {"Date": "2021-09-30T00:00:00Z", "Names": ["Cash"]}
+                        }
+                    }
+                },
+                "Response": {
+                    "StatusCode": 200
+                }
+            }
+            """;
+
+        // Act
+        var result = serializer.DeserializeJsonToArray<MappingModel>(mappingJson);
+
+        // Assert - datetime values inside the JObject pattern must remain JTokenType.String.
+        result.Should().HaveCount(1);
+        var matcher = result[0].Request!.Body!.Matcher!;
+        matcher.Name.Should().Be("JsonMatcher");
+        var patternJObject = matcher.Pattern.Should().BeOfType<JObject>().Subject;
+        patternJObject["Date"]!.Type.Should().Be(JTokenType.String,
+            "datetime-format strings inside an inline JsonMatcher body pattern must retain JTokenType.String " +
+            "after deserialization; if DateParseHandling.DateTime auto-converts them to JTokenType.Date, " +
+            "JToken.DeepEquals will fail against incoming request bodies parsed with DateParseHandling.None");
+    }
 #endif
 }

test/WireMock.Net.Tests/StatefulBehaviorTests.cs

@@ -325,26 +325,26 @@ public class StatefulBehaviorTests
         var getResponse1 = await client.GetStringAsync("/todo/items", cancelationToken);
         getResponse1.Should().Be("Buy milk");
 
-        server.Scenarios["To do list"].Name.Should().Be("To do list");
+        server.Scenarios.First(s => s.Name == "To do list").Name.Should().Be("To do list");
-        server.Scenarios["To do list"].NextState.Should().Be("TodoList State Started");
+        server.Scenarios.First(s => s.Name == "To do list").NextState.Should().Be("TodoList State Started");
-        server.Scenarios["To do list"].Started.Should().BeTrue();
+        server.Scenarios.First(s => s.Name == "To do list").Started.Should().BeTrue();
-        server.Scenarios["To do list"].Finished.Should().BeFalse();
+        server.Scenarios.First(s => s.Name == "To do list").Finished.Should().BeFalse();
 
         var postResponse = await client.PostAsync("/todo/items", new StringContent("Cancel newspaper subscription"), cancelationToken);
         postResponse.StatusCode.Should().Be(HttpStatusCode.Created);
 
-        server.Scenarios["To do list"].Name.Should().Be("To do list");
+        server.Scenarios.First(s => s.Name == "To do list").Name.Should().Be("To do list");
-        server.Scenarios["To do list"].NextState.Should().Be("Cancel newspaper item added");
+        server.Scenarios.First(s => s.Name == "To do list").NextState.Should().Be("Cancel newspaper item added");
-        server.Scenarios["To do list"].Started.Should().BeTrue();
+        server.Scenarios.First(s => s.Name == "To do list").Started.Should().BeTrue();
-        server.Scenarios["To do list"].Finished.Should().BeFalse();
+        server.Scenarios.First(s => s.Name == "To do list").Finished.Should().BeFalse();
 
         string getResponse2 = await client.GetStringAsync("/todo/items", cancelationToken);
         getResponse2.Should().Be("Buy milk;Cancel newspaper subscription");
 
-        server.Scenarios["To do list"].Name.Should().Be("To do list");
+        server.Scenarios.First(s => s.Name == "To do list").Name.Should().Be("To do list");
-        server.Scenarios["To do list"].NextState.Should().BeNull();
+        server.Scenarios.First(s => s.Name == "To do list").NextState.Should().BeNull();
-        server.Scenarios["To do list"].Started.Should().BeTrue();
+        server.Scenarios.First(s => s.Name == "To do list").Started.Should().BeTrue();
-        server.Scenarios["To do list"].Finished.Should().BeTrue();
+        server.Scenarios.First(s => s.Name == "To do list").Finished.Should().BeTrue();
 
         server.Stop();
     }
@@ -372,14 +372,14 @@ public class StatefulBehaviorTests
 
         // Act and Assert
         server.SetScenarioState(scenario, "Buy milk");
-        server.Scenarios[scenario].Should().BeEquivalentTo(new { Name = scenario, NextState = "Buy milk" });
+        server.Scenarios.First(s => s.Name == scenario).Should().BeEquivalentTo(new { Name = scenario, NextState = "Buy milk" });
-        
+
         var getResponse1 = await client.GetStringAsync("/todo/items", cancelationToken);
         getResponse1.Should().Be("Buy milk");
 
         server.SetScenarioState(scenario, "Cancel newspaper");
-        server.Scenarios[scenario].Name.Should().Be(scenario);
+        server.Scenarios.First(s => s.Name == scenario).Name.Should().Be(scenario);
-        server.Scenarios[scenario].Should().BeEquivalentTo(new { Name = scenario, NextState = "Cancel newspaper" });
+        server.Scenarios.First(s => s.Name == scenario).Should().BeEquivalentTo(new { Name = scenario, NextState = "Cancel newspaper" });
 
         var getResponse2 = await client.GetStringAsync("/todo/items", cancelationToken);
         getResponse2.Should().Be("Buy milk;Cancel newspaper subscription");
@@ -413,6 +413,120 @@ public class StatefulBehaviorTests
         action.Should().ThrowAsync<HttpRequestException>();
     }
 
+    [Fact]
+    public async Task Scenarios_FirstRequestWithDelay_StateTransitions_BeforeDelayCompletes()
+    {
+        // Arrange
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var path = $"/foo_{Guid.NewGuid()}";
+        using var server = WireMockServer.Start();
+
+        // Mapping 1: start state, has a 500 ms delay
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("1260")
+            .WillSetStateTo("State1")
+            .RespondWith(Response.Create()
+                .WithBody("delayed response")
+                .WithDelay(TimeSpan.FromMilliseconds(500)));
+
+        // Mapping 2: only matches after state has transitioned to "State1"
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("1260")
+            .WhenStateIs("State1")
+            .RespondWith(Response.Create().WithBody("immediate response"));
+
+        var client = new HttpClient();
+
+        // Act: fire request 1 but don't await it yet — it will sit in a 500 ms delay
+        var request1Task = client.GetStringAsync(server.Url + path, cancellationToken);
+
+        // Give the server a moment to match & transition state before the delay completes
+        await Task.Delay(100, cancellationToken);
+
+        // Request 2 is sent while request 1 is still being delayed.
+        // After the fix the state has already transitioned, so request 2 matches Mapping 2.
+        var response2 = await client.GetStringAsync(server.Url + path, cancellationToken);
+
+        var response1 = await request1Task;
+
+        // Assert
+        response1.Should().Be("delayed response");
+        response2.Should().Be("immediate response");
+    }
+
+    [Fact]
+    public async Task Scenarios_WithGlobalRequestProcessingDelay_StateTransitions_BeforeDelayCompletes()
+    {
+        // Arrange: use the global RequestProcessingDelay instead of a per-mapping delay
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var path = $"/foo_{Guid.NewGuid()}";
+        using var server = WireMockServer.Start();
+        server.AddGlobalProcessingDelay(TimeSpan.FromMilliseconds(500));
+
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("s")
+            .WillSetStateTo("State1")
+            .RespondWith(Response.Create().WithBody("delayed response"));
+
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("s")
+            .WhenStateIs("State1")
+            .RespondWith(Response.Create().WithBody("immediate response"));
+
+        var client = new HttpClient();
+
+        // Act
+        var request1Task = client.GetStringAsync(server.Url + path, cancellationToken);
+        await Task.Delay(100, cancellationToken);
+        var response2 = await client.GetStringAsync(server.Url + path, cancellationToken);
+        var response1 = await request1Task;
+
+        // Assert
+        response1.Should().Be("delayed response");
+        response2.Should().Be("immediate response");
+    }
+
+    [Fact]
+    public async Task Scenarios_WithDelay_And_TimesInSameState_Should_Transition_After_Required_Hits()
+    {
+        // Arrange
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var path = $"/foo_{Guid.NewGuid()}";
+        using var server = WireMockServer.Start();
+
+        // Mapping 1: requires 2 hits before transitioning; has a short delay
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("s")
+            .WillSetStateTo("State1", 2)
+            .RespondWith(Response.Create()
+                .WithBody("first")
+                .WithDelay(TimeSpan.FromMilliseconds(50)));
+
+        // Mapping 2: matches after state is "State1"
+        server
+            .Given(Request.Create().WithPath(path).UsingGet())
+            .InScenario("s")
+            .WhenStateIs("State1")
+            .RespondWith(Response.Create().WithBody("second"));
+
+        var client = new HttpClient();
+
+        // Act
+        var response1 = await client.GetStringAsync(server.Url + path, cancellationToken);
+        var response2 = await client.GetStringAsync(server.Url + path, cancellationToken);
+        var response3 = await client.GetStringAsync(server.Url + path, cancellationToken);
+
+        // Assert: state only transitions after 2 hits, so request 3 is the first to match Mapping 2
+        response1.Should().Be("first");
+        response2.Should().Be("first");
+        response3.Should().Be("second");
+    }
+
     [Fact]
     public async Task Scenarios_Should_process_request_if_equals_state_and_multiple_state_defined()
     {

test/WireMock.Net.Tests/WebSockets/WebSocketIntegrationTests.cs

@@ -706,7 +706,7 @@ public class WebSocketIntegrationTests(ITestOutputHelper output, ITestContextAcc
     public async Task WithWebSocketProxy_Should_Proxy_Multiple_TextMessages()
     {
         // Arrange - Start target echo server
-        using var exampleEchoServer = WireMockServer.Start(new WireMockServerSettings
+        var exampleEchoServer = WireMockServer.Start(new WireMockServerSettings
         {
             Logger = new TestOutputHelperWireMockLogger(output),
             Urls = ["ws://localhost:0"]
@@ -722,7 +722,7 @@ public class WebSocketIntegrationTests(ITestOutputHelper output, ITestContextAcc
             );
 
         // Arrange - Start proxy server
-        using var sut = WireMockServer.Start(new WireMockServerSettings
+        var sut = WireMockServer.Start(new WireMockServerSettings
         {
             Logger = new TestOutputHelperWireMockLogger(output),
             Urls = ["ws://localhost:0"]
@@ -755,13 +755,21 @@ public class WebSocketIntegrationTests(ITestOutputHelper output, ITestContextAcc
         }
 
         await client.CloseAsync(WebSocketCloseStatus.NormalClosure, "Test complete", _ct);
+
+        await Task.Delay(250, _ct);
+
+        sut.Stop();
+        sut.Dispose();
+
+        exampleEchoServer.Stop();
+        exampleEchoServer.Dispose();
     }
 
     [Fact]
     public async Task WithWebSocketProxy_Should_Proxy_Binary_Messages()
     {
         // Arrange - Start target echo server
-        using var exampleEchoServer = WireMockServer.Start(new WireMockServerSettings
+        var exampleEchoServer = WireMockServer.Start(new WireMockServerSettings
         {
             Logger = new TestOutputHelperWireMockLogger(output),
             Urls = ["ws://localhost:0"]
@@ -777,7 +785,7 @@ public class WebSocketIntegrationTests(ITestOutputHelper output, ITestContextAcc
             );
 
         // Arrange - Start proxy server
-        using var sut = WireMockServer.Start(new WireMockServerSettings
+        var sut = WireMockServer.Start(new WireMockServerSettings
         {
             Logger = new TestOutputHelperWireMockLogger(output),
             Urls = ["ws://localhost:0"]
@@ -811,6 +819,14 @@ public class WebSocketIntegrationTests(ITestOutputHelper output, ITestContextAcc
         receivedData.Should().BeEquivalentTo(testData, "binary data should be proxied and echoed back");
 
         await client.CloseAsync(WebSocketCloseStatus.NormalClosure, "Test complete", _ct);
+
+        await Task.Delay(250, _ct);
+
+        sut.Stop();
+        sut.Dispose();
+
+        exampleEchoServer.Stop();
+        exampleEchoServer.Dispose();
     }
 
     [Fact]

test/WireMock.Net.Tests/WireMockServerTests.WithBody.cs

@@ -4,10 +4,13 @@ using System.Net;
 using System.Net.Http;
 using System.Net.Http.Json;
 using System.Text;
+using System.Text.Json.Serialization;
+using JsonConverter.System.Text.Json;
 using WireMock.Matchers;
 using WireMock.RequestBuilders;
 using WireMock.ResponseBuilders;
 using WireMock.Server;
+using WireMock.Settings;
 
 namespace WireMock.Net.Tests;
 
@@ -18,11 +21,41 @@ public partial class WireMockServerTests
         public string? Hi { get; set; }
     }
 
+    public class Person
+    {
+        [JsonPropertyName("first_name")]
+        public string FirstName { get; set; } = string.Empty;
+
+        [JsonPropertyName("last_name")]
+        public string LastName { get; set; } = string.Empty;
+    }
+
+    [Fact]
+    public async Task WireMockServer_WithBodyAsJson_UsingWireMockServerSettings_SystemTextJsonConverter_ShouldReturnCorrectResponse()
+    {
+        // Arange
+        var person = new Person { FirstName = "John", LastName = "Smith" };
+
+        using var server = WireMockServer.Start(new WireMockServerSettings
+        {
+            DefaultJsonSerializer = new SystemTextJsonConverter()
+        });
+
+        // Act
+        server
+            .Given(Request.Create().UsingAnyMethod())
+            .RespondWith(Response.Create().WithBodyAsJson(person));
+
+        var response = await server.CreateClient().GetStringAsync("/", _ct);
+
+        // Assert
+        response.Should().BeEquivalentTo("{\"first_name\":\"John\",\"last_name\":\"Smith\"}");
+    }
+
     [Fact]
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsJsonAsync_And_MultipleJmesPathMatchers_ShouldMatch()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
             Request.Create()
@@ -56,7 +89,7 @@ public partial class WireMockServerTests
         var requestUri = new Uri($"http://localhost:{server.Port}/a");
 
         var json = new { requestId = "1", value = "A" };
-        var response = await server.CreateClient().PostAsJsonAsync(requestUri, json, cancellationToken);
+        var response = await server.CreateClient().PostAsJsonAsync(requestUri, json, _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -68,7 +101,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsJsonAsync_And_MultipleJmesPathMatchers_ShouldMatch_BestMatching()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
                 Request.Create()
@@ -105,7 +137,7 @@ public partial class WireMockServerTests
         var requestUri = new Uri($"http://localhost:{server.Port}/a");
 
         var json = new { extra = "X", requestId = "1", value = "A" };
-        var response = await server.CreateClient().PostAsJsonAsync(requestUri, json, cancellationToken);
+        var response = await server.CreateClient().PostAsJsonAsync(requestUri, json, _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -117,7 +149,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsJsonAsync_And_WildcardMatcher_ShouldMatch()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
                 Request.Create().UsingPost().WithPath("/foo").WithBody(new WildcardMatcher("*Hello*"))
@@ -132,7 +163,7 @@ public partial class WireMockServerTests
         };
 
         // Act
-        var response = await new HttpClient().PostAsJsonAsync("http://localhost:" + server.Ports[0] + "/foo", jsonObject, cancellationToken);
+        var response = await new HttpClient().PostAsJsonAsync("http://localhost:" + server.Ports[0] + "/foo", jsonObject, _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -144,7 +175,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsync_And_WildcardMatcher_ShouldMatch()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
                 Request.Create().UsingPost().WithPath("/foo").WithBody(new WildcardMatcher("*Hello*"))
@@ -154,7 +184,7 @@ public partial class WireMockServerTests
             );
 
         // Act
-        var response = await new HttpClient().PostAsync("http://localhost:" + server.Ports[0] + "/foo", new StringContent("{ Hi = \"Hello World\" }"), cancellationToken);
+        var response = await new HttpClient().PostAsync("http://localhost:" + server.Ports[0] + "/foo", new StringContent("{ Hi = \"Hello World\" }"), _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -166,7 +196,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsync_And_JsonPartialWildcardMatcher_ShouldMatch()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
 
         var matcher = new JsonPartialWildcardMatcher(new { method = "initialize", id = "^[a-f0-9]{32}-[0-9]$" }, ignoreCase: true, regex: true);
@@ -188,13 +217,13 @@ public partial class WireMockServerTests
         // Act
         var content = "{\"jsonrpc\":\"2.0\",\"id\":\"ec475f56d4694b48bc737500ba575b35-1\",\"method\":\"initialize\",\"params\":{\"protocolVersion\":\"2024-11-05\",\"capabilities\":{},\"clientInfo\":{\"name\":\"GitHub Test\",\"version\":\"1.0.0\"}}}";
         var response = await new HttpClient()
-            .PostAsync($"{server.Url}/foo", new StringContent(content, Encoding.UTF8, "application/json"), cancellationToken)
+            .PostAsync($"{server.Url}/foo", new StringContent(content, Encoding.UTF8, "application/json"), _ct)
 ;
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
 
-        var responseText = await response.Content.ReadAsStringAsync(cancellationToken);
+        var responseText = await response.Content.ReadAsStringAsync(_ct);
         responseText.Should().Contain("ec475f56d4694b48bc737500ba575b35-1");
     }
 
@@ -203,8 +232,7 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsJson_Using_PostAsync_And_JsonPartialWildcardMatcher_And_SystemTextJson_ShouldMatch()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
+        using var server = WireMockServer.Start(x => x.DefaultJsonSerializer = new SystemTextJsonConverter());
-        using var server = WireMockServer.Start(x => x.DefaultJsonSerializer = new JsonConverter.System.Text.Json.SystemTextJsonConverter() );
 
         var matcher = new JsonPartialWildcardMatcher(new { id = "^[a-f0-9]{32}-[0-9]$" }, ignoreCase: true, regex: true);
         server.Given(Request.Create()
@@ -220,12 +248,12 @@ public partial class WireMockServerTests
         // Act
         var content = """{"id":"ec475f56d4694b48bc737500ba575b35-1"}""";
         using var httpClient = new HttpClient();
-        var response = await httpClient.PostAsync($"{server.Url}/system-text-json", new StringContent(content, Encoding.UTF8, "application/json"), cancellationToken);
+        var response = await httpClient.PostAsync($"{server.Url}/system-text-json", new StringContent(content, Encoding.UTF8, "application/json"), _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
 
-        var responseText = await response.Content.ReadAsStringAsync(cancellationToken);
+        var responseText = await response.Content.ReadAsStringAsync(_ct);
         responseText.Should().Contain("OK");
     }
 #endif
@@ -234,7 +262,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsFormUrlEncoded_Using_PostAsync_And_WithFunc()
     {
         // Arrange
-        var cancelationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
             Request.Create()
@@ -249,7 +276,7 @@ public partial class WireMockServerTests
         // Act
         var content = new FormUrlEncodedContent([new KeyValuePair<string, string>("key1", "value1")]);
         var response = await new HttpClient()
-            .PostAsync($"{server.Url}/foo", content, cancelationToken);
+            .PostAsync($"{server.Url}/foo", content, _ct);
 
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -261,7 +288,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsFormUrlEncoded_Using_PostAsync_And_WithExactMatcher()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server.Given(
                 Request.Create()
@@ -282,7 +308,7 @@ public partial class WireMockServerTests
             new KeyValuePair<string, string>("email", "johndoe@example.com")
         ]);
         using var httpClient = new HttpClient();
-        var response = await httpClient.PostAsync($"{server.Url}/foo", content, cancellationToken)
+        var response = await httpClient.PostAsync($"{server.Url}/foo", content, _ct)
 ;
         // Assert
         response.StatusCode.Should().Be(HttpStatusCode.OK);
@@ -294,7 +320,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithBodyAsFormUrlEncoded_Using_PostAsync_And_WithFormUrlEncodedMatcher()
     {
         // Arrange
-        var cancelationToken = TestContext.Current.CancellationToken;
         var matcher = new FormUrlEncodedMatcher(["email=johndoe@example.com", "name=John Doe"]);
         using var server = WireMockServer.Start();
         server.Given(
@@ -326,7 +351,7 @@ public partial class WireMockServerTests
             new KeyValuePair<string, string>("email", "johndoe@example.com")
         ]);
         var responseOrdered = await new HttpClient()
-            .PostAsync($"{server.Url}/foo", contentOrdered, cancelationToken)
+            .PostAsync($"{server.Url}/foo", contentOrdered, _ct)
 ;
 
         // Assert 1
@@ -340,7 +365,7 @@ public partial class WireMockServerTests
             new KeyValuePair<string, string>("name", "John Doe"),
         ]);
         var responseUnordered = await new HttpClient()
-            .PostAsync($"{server.Url}/bar", contentUnordered, cancelationToken)
+            .PostAsync($"{server.Url}/bar", contentUnordered, _ct)
 ;
 
         // Assert 2
@@ -353,7 +378,6 @@ public partial class WireMockServerTests
     public async Task WireMockServer_WithSseBody()
     {
         // Arrange
-        var cancellationToken = TestContext.Current.CancellationToken;
         using var server = WireMockServer.Start();
         server
             .WhenRequest(r => r
@@ -387,9 +411,8 @@ public partial class WireMockServerTests
         using var client = new HttpClient();
 
         // Act 1
-        var normal = await client.GetAsync(server.Url, cancellationToken)
+        var normal = await client.GetAsync(server.Url, _ct);
-;
+        (await normal.Content.ReadAsStringAsync(_ct)).Should().Be("normal");
-        (await normal.Content.ReadAsStringAsync(cancellationToken)).Should().Be("normal");
 
         // Act 2
         using var response = await client.GetStreamAsync($"{server.Url}/sse", _ct);

test/WireMock.Net.Tests/WireMockServerTests.cs

@@ -431,8 +431,13 @@ public partial class WireMockServerTests(ITestOutputHelper testOutputHelper)
         using var server = WireMockServer.Start();
 
         server
-            .Given(Request.Create().WithPath(path).UsingHead())
+            .WhenRequest(r => r
-            .RespondWith(Response.Create().WithHeader(HttpKnownHeaderNames.ContentLength, length));
+                .WithPath(path)
+                .UsingHead()
+            )
+            .ThenRespondWith(r => r
+                .WithHeader(HttpKnownHeaderNames.ContentLength, length)
+            );
 
         // Act
         var httpRequestMessage = new HttpRequestMessage(HttpMethod.Head, path);
@@ -442,6 +447,45 @@ public partial class WireMockServerTests(ITestOutputHelper testOutputHelper)
         response.Content.Headers.GetValues(HttpKnownHeaderNames.ContentLength).Should().Contain(length);
     }
 
+#if NET8_0_OR_GREATER
+    [Theory]
+    [InlineData("DELETE")]
+    [InlineData("GET")]
+    [InlineData("OPTIONS")]
+    [InlineData("PATCH")]
+    [InlineData("POST")]
+    [InlineData("PUT")]
+    [InlineData("TRACE")]
+    public async Task WireMockServer_Should_LogAndThrowExceptionWhenInvalidContentLength(string method)
+    {
+        // Assign
+        const string length = "42";
+        var path = $"/InvalidContentLength_{Guid.NewGuid()}";
+        using var server = WireMockServer.Start(new WireMockServerSettings
+        {
+            Logger = new TestOutputHelperWireMockLogger(testOutputHelper)
+        });
+
+        server
+            .WhenRequest(r => r
+                .WithPath(path)
+                .UsingAnyMethod()
+            )
+            .ThenRespondWith(r => r
+                .WithStatusCode(HttpStatusCode.OK)
+                .WithHeader(HttpKnownHeaderNames.ContentLength, length)
+            );
+
+        // Act
+        var httpRequestMessage = new HttpRequestMessage(HttpMethod.Parse(method), path);
+        var response = await server.CreateClient().SendAsync(httpRequestMessage, _ct);
+
+        // Assert
+        response.StatusCode.Should().Be(HttpStatusCode.InternalServerError);
+        testOutputHelper.Output.Should().Contain($"Response Content-Length mismatch: too few bytes written (0 of {length}).");
+    }
+#endif
+
     [Theory]
     [InlineData("TRACE")]
     [InlineData("GET")]