Add project files.

src/modules/Elsa.Alterations.MassTransit/Consumers/RunAlterationJobConsumer.cs

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+using Elsa.Alterations.Core.Contracts;
+using Elsa.Alterations.MassTransit.Messages;
+using MassTransit;
+
+namespace Elsa.Alterations.MassTransit.Consumers;
+
+/// <summary>
+/// Consumes <see cref="RunAlterationJob"/> messages.
+/// </summary>
+public class RunAlterationJobConsumer : IConsumer<RunAlterationJob>
+{
+    private readonly IAlterationJobRunner _alterationJobRunner;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="RunAlterationJobConsumer"/> class.
+    /// </summary>
+    public RunAlterationJobConsumer(IAlterationJobRunner alterationJobRunner)
+    {
+        _alterationJobRunner = alterationJobRunner;
+    }
+    
+    /// <inheritdoc />
+    public async Task Consume(ConsumeContext<RunAlterationJob> context)
+    {
+        await _alterationJobRunner.RunAsync(context.Message.JobId, context.CancellationToken);
+    }
+}

src/modules/Elsa.Alterations.MassTransit/Elsa.Alterations.MassTransit.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <Description>
+            Provides alteration background job runners using MassTransit.
+        </Description>
+        <PackageTags>elsa module alterations masstransit</PackageTags>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\Elsa.Alterations\Elsa.Alterations.csproj" />
+        <ProjectReference Include="..\Elsa.MassTransit\Elsa.MassTransit.csproj" />
+    </ItemGroup>
+
+</Project>

src/modules/Elsa.Alterations.MassTransit/Extensions/ModuleExtensions.cs

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+using Elsa.Alterations.Features;
+using Elsa.Alterations.MassTransit.Features;
+using Elsa.Extensions;
+using Elsa.Features.Services;
+
+namespace Elsa.Alterations.MassTransit.Extensions;
+
+/// <summary>
+/// Adds the <see cref="AlterationsFeature"/>.
+/// </summary>
+public static class ModuleExtensions
+{
+    /// <summary>
+    /// Adds the <see cref="MassTransitAlterationsFeature"/>.
+    /// </summary>
+    public static IModule UseMassTransitDispatcher(this AlterationsFeature alterations, Action<MassTransitAlterationsFeature>? configure = default)
+    {
+        return alterations.Module.Use(configure);
+    }
+}

src/modules/Elsa.Alterations.MassTransit/Features/AlterationsMassTransitFeature.cs

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+using Elsa.Alterations.Features;
+using Elsa.Alterations.MassTransit.Consumers;
+using Elsa.Alterations.MassTransit.Messages;
+using Elsa.Alterations.MassTransit.Services;
+using Elsa.Extensions;
+using Elsa.Features.Abstractions;
+using Elsa.Features.Attributes;
+using Elsa.Features.Services;
+using Elsa.MassTransit.Features;
+using MassTransit;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Elsa.Alterations.MassTransit.Features;
+
+/// <summary>
+/// A feature for enabling the Alterations MassTransit feature.
+/// </summary>
+[DependsOn(typeof(MassTransitFeature))]
+[DependsOn(typeof(AlterationsFeature))]
+public class MassTransitAlterationsFeature : FeatureBase
+{
+    /// <inheritdoc />
+    public MassTransitAlterationsFeature(IModule module) : base(module)
+    {
+    }
+
+    /// <inheritdoc />
+    public override void Configure()
+    {
+        Module.Configure<AlterationsFeature>(feature => feature.AlterationJobDispatcherFactory = sp => sp.GetRequiredService<MassTransitAlterationJobDispatcher>());
+        var queueName = KebabCaseEndpointNameFormatter.Instance.Consumer<RunAlterationJobConsumer>();
+        var queueAddress = new Uri($"queue:elsa-{queueName}");
+        EndpointConvention.Map<RunAlterationJob>(queueAddress);
+        Module.AddMassTransitConsumer<RunAlterationJobConsumer>(queueName);
+    }
+
+    /// <inheritdoc />
+    public override void Apply()
+    {
+        Services.AddScoped<MassTransitAlterationJobDispatcher>();
+    }
+}

src/modules/Elsa.Alterations.MassTransit/FodyWeavers.xml

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+<Weavers xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="FodyWeavers.xsd">
+  <ConfigureAwait />
+</Weavers>

src/modules/Elsa.Alterations.MassTransit/Messages/RunAlterationJob.cs

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+namespace Elsa.Alterations.MassTransit.Messages;
+
+/// <summary>
+/// Represents a request to run an alteration job.
+/// </summary>
+/// <param name="JobId">The job ID.</param>
+public record RunAlterationJob(string JobId);

src/modules/Elsa.Alterations.MassTransit/Readme.md

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+# MassTransit Alterations Background Runner
+
+This module provides an implementation that processes alteration plans in the background using a MassTransit dispatcher and consumer.
+This implementation is more resilient than the in-memory queue implementation provided by **Elsa.Alterations.BackgroundRunner** because it uses a message broker to persist messages.

src/modules/Elsa.Alterations.MassTransit/Services/MassTransitAlterationJobDispatcher.cs

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+using Elsa.Alterations.Core.Contracts;
+using Elsa.Alterations.MassTransit.Messages;
+using MassTransit;
+
+namespace Elsa.Alterations.MassTransit.Services;
+
+/// <summary>
+/// Dispatches an alteration job for execution using MassTransit.
+/// </summary>
+public class MassTransitAlterationJobDispatcher : IAlterationJobDispatcher
+{
+    private readonly IBus _bus;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="MassTransitAlterationJobDispatcher"/> class.
+    /// </summary>
+    public MassTransitAlterationJobDispatcher(IBus bus)
+    {
+        _bus = bus;
+    }
+    
+    /// <inheritdoc />
+    public async ValueTask DispatchAsync(string jobId, CancellationToken cancellationToken = default)
+    {
+        var message = new RunAlterationJob(jobId);
+        await _bus.Send(message, cancellationToken);
+    }
+}