diff --git a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Sessions/SessionWorkerClientFactoryFakeWorkerTests.cs b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Sessions/SessionWorkerClientFactoryFakeWorkerTests.cs
index a61cb96..11b09d5 100644
--- a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Sessions/SessionWorkerClientFactoryFakeWorkerTests.cs
+++ b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Sessions/SessionWorkerClientFactoryFakeWorkerTests.cs
@@ -7,6 +7,7 @@ using ZB.MOM.WW.MxGateway.Server.Metrics;
 using ZB.MOM.WW.MxGateway.Server.Sessions;
 using ZB.MOM.WW.MxGateway.Server.Workers;
 using ZB.MOM.WW.MxGateway.Tests.Gateway.Workers.Fakes;
+using ZB.MOM.WW.MxGateway.Tests.TestSupport;
 
 namespace ZB.MOM.WW.MxGateway.Tests.Gateway.Sessions;
 
@@ -330,62 +331,4 @@ public sealed class SessionWorkerClientFactoryFakeWorkerTests : IAsyncDisposable
             DateTimeOffset.UtcNow);
     }
 
-    /// <summary>
-    /// Fake worker process for testing process lifecycle. <see cref="WaitForExitAsync"/>
-    /// awaits a <see cref="TaskCompletionSource"/> completed only by
-    /// <see cref="Kill"/> or <see cref="MarkExited"/>, so a caller observing
-    /// completion can trust that exit actually happened — bringing this fake into
-    /// parity with the smoke-test variant in <c>GatewayEndToEndFakeWorkerSmokeTests</c>
-    /// (Tests-015 / Tests-023). This removes the latent regression vector where a
-    /// future <c>Assert.True(launcher.Process.HasExited)</c> in this file would
-    /// pass spuriously regardless of whether the worker truly exited.
-    /// </summary>
-    private sealed class FakeWorkerProcess(int processId) : IWorkerProcess
-    {
-        private readonly TaskCompletionSource _exited = new(TaskCreationOptions.RunContinuationsAsynchronously);
-        private bool _disposed;
-
-        /// <inheritdoc />
-        public int Id { get; } = processId;
-
-        /// <summary>Gets a value indicating whether the process has exited.</summary>
-        public bool HasExited { get; private set; }
-
-        /// <summary>Gets the process exit code, or null if the process has not exited.</summary>
-        public int? ExitCode { get; private set; }
-
-        /// <summary>Gets the number of times the Kill method was called.</summary>
-        public int KillCount { get; private set; }
-
-        /// <inheritdoc />
-        public ValueTask WaitForExitAsync(CancellationToken cancellationToken)
-        {
-            return new ValueTask(_exited.Task.WaitAsync(cancellationToken));
-        }
-
-        /// <inheritdoc />
-        public void Kill(bool entireProcessTree)
-        {
-            KillCount++;
-            MarkExited(-1);
-        }
-
-        /// <inheritdoc />
-        public void Dispose()
-        {
-            _disposed = true;
-        }
-
-        /// <summary>Gets a value indicating whether this process has been disposed.</summary>
-        public bool IsDisposed => _disposed;
-
-        /// <summary>Marks the process as exited with the specified exit code.</summary>
-        /// <param name="exitCode">The process exit code.</param>
-        public void MarkExited(int exitCode)
-        {
-            HasExited = true;
-            ExitCode = exitCode;
-            _exited.TrySetResult();
-        }
-    }
 }
diff --git a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerClientTests.cs b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerClientTests.cs
index 7d46680..9750c14 100644
--- a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerClientTests.cs
+++ b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerClientTests.cs
@@ -158,7 +158,7 @@ public sealed class WorkerClientTests
     public async Task ReadLoop_WhenClientFaults_KillsOwnedWorkerProcess()
     {
         await using PipePair pipePair = await PipePair.CreateAsync();
-        FakeWorkerProcess process = new();
+        FakeWorkerProcess process = new(WorkerProcessId);
         await using WorkerClient client = CreateClient(
             pipePair,
             new WorkerClientOptions
@@ -309,7 +309,7 @@ public sealed class WorkerClientTests
     public async Task DisposeAsync_WhenOwnedWorkerStillRuns_KillsProcessBeforeDisposing()
     {
         await using PipePair pipePair = await PipePair.CreateAsync();
-        FakeWorkerProcess process = new();
+        FakeWorkerProcess process = new(WorkerProcessId);
         WorkerClient client = CreateClient(pipePair, processHandle: CreateProcessHandle(process));
 
         await client.DisposeAsync().AsTask().WaitAsync(TestTimeout);
@@ -764,49 +764,4 @@ public sealed class WorkerClientTests
         }
     }
 
-    private sealed class FakeWorkerProcess : IWorkerProcess
-    {
-        private readonly TaskCompletionSource _exited = new(TaskCreationOptions.RunContinuationsAsynchronously);
-
-        /// <summary>Gets the process ID.</summary>
-        public int Id { get; } = WorkerProcessId;
-
-        /// <summary>Gets a value indicating whether the process has exited.</summary>
-        public bool HasExited { get; private set; }
-
-        /// <summary>Gets the process exit code.</summary>
-        public int? ExitCode { get; private set; }
-
-        /// <summary>Gets the number of times kill was called.</summary>
-        public int KillCount { get; private set; }
-
-        /// <summary>Gets the last kill request's entire process tree flag.</summary>
-        public bool KillEntireProcessTree { get; private set; }
-
-        /// <summary>Gets a value indicating whether dispose was called.</summary>
-        public bool Disposed { get; private set; }
-
-        /// <inheritdoc />
-        public ValueTask WaitForExitAsync(CancellationToken cancellationToken)
-        {
-            return new ValueTask(_exited.Task.WaitAsync(cancellationToken));
-        }
-
-        /// <summary>Records a kill request.</summary>
-        /// <param name="entireProcessTree">Whether to kill the entire process tree.</param>
-        public void Kill(bool entireProcessTree)
-        {
-            KillCount++;
-            KillEntireProcessTree = entireProcessTree;
-            HasExited = true;
-            ExitCode = -1;
-            _exited.TrySetResult();
-        }
-
-        /// <inheritdoc />
-        public void Dispose()
-        {
-            Disposed = true;
-        }
-    }
 }
diff --git a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerProcessLauncherTests.cs b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerProcessLauncherTests.cs
index f8f93a5..adeacf1 100644
--- a/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerProcessLauncherTests.cs
+++ b/src/ZB.MOM.WW.MxGateway.Tests/Gateway/Workers/WorkerProcessLauncherTests.cs
@@ -4,6 +4,7 @@ using ZB.MOM.WW.MxGateway.Contracts;
 using ZB.MOM.WW.MxGateway.Server.Configuration;
 using ZB.MOM.WW.MxGateway.Server.Metrics;
 using ZB.MOM.WW.MxGateway.Server.Workers;
+using ZB.MOM.WW.MxGateway.Tests.TestSupport;
 
 namespace ZB.MOM.WW.MxGateway.Tests.Gateway.Workers;
 
@@ -240,45 +241,6 @@ public sealed class WorkerProcessLauncherTests
         }
     }
 
-    /// <summary>Fake worker process for testing process lifecycle and exit behavior.</summary>
-    private sealed class FakeWorkerProcess(int processId) : IWorkerProcess
-    {
-        /// <inheritdoc />
-        public int Id { get; } = processId;
-
-        /// <summary>Gets or sets a value indicating whether the process has exited.</summary>
-        public bool HasExited { get; set; }
-
-        /// <summary>Gets or sets the process exit code.</summary>
-        public int? ExitCode { get; set; }
-
-        /// <summary>Gets a value indicating whether the Dispose method was called.</summary>
-        public bool DisposeCalled { get; private set; }
-
-        /// <summary>Gets a value indicating whether the Kill method was called.</summary>
-        public bool KillCalled { get; private set; }
-
-        /// <inheritdoc />
-        public ValueTask WaitForExitAsync(CancellationToken cancellationToken)
-        {
-            return ValueTask.CompletedTask;
-        }
-
-        /// <inheritdoc />
-        public void Kill(bool entireProcessTree)
-        {
-            Assert.True(entireProcessTree);
-            KillCalled = true;
-            HasExited = true;
-        }
-
-        /// <inheritdoc />
-        public void Dispose()
-        {
-            DisposeCalled = true;
-        }
-    }
-
     /// <summary>Fake startup probe that immediately succeeds.</summary>
     private sealed class SucceedingStartupProbe : IWorkerStartupProbe
     {
diff --git a/src/ZB.MOM.WW.MxGateway.Tests/TestSupport/FakeWorkerProcess.cs b/src/ZB.MOM.WW.MxGateway.Tests/TestSupport/FakeWorkerProcess.cs
index f65897f..2bb0386 100644
--- a/src/ZB.MOM.WW.MxGateway.Tests/TestSupport/FakeWorkerProcess.cs
+++ b/src/ZB.MOM.WW.MxGateway.Tests/TestSupport/FakeWorkerProcess.cs
@@ -4,10 +4,21 @@ namespace ZB.MOM.WW.MxGateway.Tests.TestSupport;
 
 /// <summary>
 /// Lightweight in-process stand-in for <see cref="IWorkerProcess"/> used by fake worker
-/// launchers in end-to-end tests.  Call <see cref="MarkExited"/> from the fake worker
-/// body once the shutdown-ack handshake is complete so that callers awaiting
-/// <see cref="WaitForExitAsync"/> observe real exit rather than a timeout.
+/// launchers and lifecycle tests.
 /// </summary>
+/// <remarks>
+/// <para>
+/// <see cref="WaitForExitAsync"/> awaits a <see cref="TaskCompletionSource"/> that is
+/// completed only by <see cref="Kill"/> or <see cref="MarkExited"/>, so a caller observing
+/// completion can trust that exit actually happened rather than passing spuriously.
+/// </para>
+/// <para>
+/// The disposal and kill bookkeeping is exposed under several aliases
+/// (<see cref="IsDisposed"/>/<see cref="DisposeCalled"/>/<see cref="Disposed"/>;
+/// <see cref="KillCount"/>/<see cref="KillCalled"/>) so the various lifecycle tests can
+/// keep their existing assertion vocabulary while sharing one definition.
+/// </para>
+/// </remarks>
 public sealed class FakeWorkerProcess(int processId) : IWorkerProcess
 {
     private readonly TaskCompletionSource _exited = new(TaskCreationOptions.RunContinuationsAsynchronously);
@@ -15,23 +26,44 @@ public sealed class FakeWorkerProcess(int processId) : IWorkerProcess
     /// <summary>Gets the process identifier.</summary>
     public int Id { get; } = processId;
 
-    /// <summary>Gets a value indicating whether the process has exited.</summary>
-    public bool HasExited { get; private set; }
+    /// <summary>Gets or sets a value indicating whether the process has exited.</summary>
+    public bool HasExited { get; set; }
 
-    /// <summary>Gets the exit code of the process, or <see langword="null"/> if it has not exited.</summary>
-    public int? ExitCode { get; private set; }
+    /// <summary>Gets or sets the exit code of the process, or <see langword="null"/> if it has not exited.</summary>
+    public int? ExitCode { get; set; }
+
+    /// <summary>Gets the number of times <see cref="Kill"/> was called.</summary>
+    public int KillCount { get; private set; }
+
+    /// <summary>Gets a value indicating whether <see cref="Kill"/> was called at least once.</summary>
+    public bool KillCalled => KillCount > 0;
+
+    /// <summary>Gets the <c>entireProcessTree</c> flag from the most recent <see cref="Kill"/> call.</summary>
+    public bool KillEntireProcessTree { get; private set; }
+
+    /// <summary>Gets a value indicating whether <see cref="Dispose"/> was called.</summary>
+    public bool IsDisposed { get; private set; }
+
+    /// <summary>Gets a value indicating whether <see cref="Dispose"/> was called.</summary>
+    public bool DisposeCalled => IsDisposed;
+
+    /// <summary>Gets a value indicating whether <see cref="Dispose"/> was called.</summary>
+    public bool Disposed => IsDisposed;
 
     /// <inheritdoc />
     public ValueTask WaitForExitAsync(CancellationToken cancellationToken) =>
         new(_exited.Task.WaitAsync(cancellationToken));
 
     /// <inheritdoc />
-    public void Kill(bool entireProcessTree) => MarkExited(-1);
+    public void Kill(bool entireProcessTree)
+    {
+        KillCount++;
+        KillEntireProcessTree = entireProcessTree;
+        MarkExited(-1);
+    }
 
     /// <inheritdoc />
-    public void Dispose()
-    {
-    }
+    public void Dispose() => IsDisposed = true;
 
     /// <summary>
     /// Marks the process as exited with the specified exit code and unblocks