diff --git a/ECMJobRunner.Application/DependencyInjection.cs b/ECMJobRunner.Application/DependencyInjection.cs
new file mode 100644
index 0000000..060e1b9
--- /dev/null
+++ b/ECMJobRunner.Application/DependencyInjection.cs
@@ -0,0 +1,39 @@
+using ECMJobRunner.Application.Behaviors;
+using MediatR;
+using Microsoft.Extensions.DependencyInjection;
+using System.Reflection;
+
+namespace ECMJobRunner.Application
+{
+    /// <summary>
+    /// Extension methods for configuring Application layer services
+    /// </summary>
+    public static class DependencyInjection
+    {
+        /// <summary>
+        /// Adds Application layer services to the dependency injection container
+        /// Registers MediatR, pipeline behaviors, and AutoMapper
+        /// </summary>
+        /// <param name="services">The service collection</param>
+        /// <returns>The service collection for chaining</returns>
+        public static IServiceCollection AddApplication(this IServiceCollection services)
+        {
+            var assembly = Assembly.GetExecutingAssembly();
+
+            // Register MediatR with all handlers from this assembly
+#if NET48
+            services.AddMediatR(assembly);
+#else
+            services.AddMediatR(cfg => cfg.RegisterServicesFromAssembly(assembly));
+#endif
+
+            // Register pipeline behaviors in execution order
+            // Order matters: MainQuery -> CheckQuery -> ReCRequest
+            services.AddTransient(typeof(IPipelineBehavior<,>), typeof(MainQueryExecutionBehavior<,>));
+            services.AddTransient(typeof(IPipelineBehavior<,>), typeof(CheckQueryExecutionBehavior<,>));
+            services.AddTransient(typeof(IPipelineBehavior<,>), typeof(ReCRequestExecutionBehavior<,>));
+
+            return services;
+        }
+    }
+}
diff --git a/ECMJobRunner.Application/ECMJobRunner.Application.csproj b/ECMJobRunner.Application/ECMJobRunner.Application.csproj
index 557368e..544e80d 100644
--- a/ECMJobRunner.Application/ECMJobRunner.Application.csproj
+++ b/ECMJobRunner.Application/ECMJobRunner.Application.csproj
@@ -30,6 +30,7 @@
 		<PackageReference Include="AutoMapper.Extensions.Microsoft.DependencyInjection" Version="8.1.1" />
 		<!-- MediatR for .NET Framework 4.8 -->
 		<PackageReference Include="MediatR" Version="9.0.0" />
+		<PackageReference Include="MediatR.Extensions.Microsoft.DependencyInjection" Version="9.0.0" />
 	</ItemGroup>
 
 	<ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">
diff --git a/ECMJobRunner.Application/README.md b/ECMJobRunner.Application/README.md
new file mode 100644
index 0000000..352b82c
--- /dev/null
+++ b/ECMJobRunner.Application/README.md
@@ -0,0 +1,373 @@
+# ECMJobRunner.Application - DEX Job Integration
+
+## Overview
+
+This document describes the **DEX Job triggering system** implemented in `ECMJobRunner.Application` using the **CQRS pattern with MediatR** and **Pipeline Behaviors**.
+
+## Architecture
+
+### Commands
+
+#### `TriggeringDEXJobBatchCommand`
+Orchestrates batch job execution for a profile.
+
+**Properties:**
+- `ProfileId` (int): Profile ID to trigger all associated SQL jobs
+
+**Handler:**
+- Creates a unique 20-character timestamp-based batch ID
+- Retrieves all SQL jobs for the profile
+- Executes each job sequentially using `TriggeringDEXJobCommand`
+
+**Usage:**
+```csharp
+var command = new TriggeringDEXJobBatchCommand { ProfileId = 123 };
+await mediator.Send(command);
+```
+
+#### `TriggeringDEXJobCommand`
+Executes a single DEX job with three-stage pipeline.
+
+**Properties:**
+- `Job` (ProfileSqlJob): The SQL job to execute
+- `BatchId` (string): Unique batch identifier
+
+**Execution Pipeline:**
+1. **MainQueryExecutionBehavior**: Executes main SQL query with batch ID placeholder replacement
+2. **CheckQueryExecutionBehavior**: Validates execution with return value check (> 0)
+3. **ReCRequestExecutionBehavior**: Invokes ReC API with batch ID reference
+
+**Handler:**
+- Empty handler - all logic delegated to pipeline behaviors
+
+**Usage:**
+```csharp
+var command = new TriggeringDEXJobCommand 
+{ 
+    Job = profileSqlJob,
+    BatchId = "20260711143025123456"
+};
+await mediator.Send(command);
+```
+
+### Pipeline Behaviors
+
+#### Execution Order
+1. `MainQueryExecutionBehavior<,>` - SQL main query execution
+2. `CheckQueryExecutionBehavior<,>` - SQL check query validation
+3. `ReCRequestExecutionBehavior<,>` - ReC HTTP request
+
+Each behavior:
+- Checks if request is `TriggeringDEXJobCommand`
+- Executes its stage logic
+- Calls `next()` to continue pipeline
+
+## Configuration
+
+### appsettings.json
+
+```json
+{
+  "DexJob": {
+    "Error": {
+      "MainQuery": {
+        "OnExecution": "Stop",
+        "IfNullOrWhiteSpace": "Ignore",
+        "OnUnexpectedResult": "Stop"
+      },
+      "CheckQuery": {
+        "OnExecution": "Stop",
+        "IfNullOrWhiteSpace": "Ignore",
+        "OnUnexpectedResult": "Stop"
+      },
+      "ReCRequest": {
+        "OnSending": "Stop"
+      }
+    },
+    "Placeholders": {
+      "BatchId": {
+        "Pattern": "#INT#BATCH_ID",
+        "RegexOptions": "IgnoreCase"
+      }
+    }
+  }
+}
+```
+
+### Configuration Options
+
+#### `DexJobOptions`
+Root configuration object for DEX job execution.
+
+**Properties:**
+- `Error` (DexJobErrorHandlingOptions): Error handling configuration
+- `Placeholders` (PlaceHolderOptions): Placeholder replacement configuration
+
+#### `DexJobErrorHandlingOptions`
+Hierarchical error handling per stage.
+
+**Properties:**
+- `MainQuery` (SqlQueryErrorHandlingOptions): Main query error handling
+- `CheckQuery` (SqlQueryErrorHandlingOptions): Check query error handling
+- `ReCRequest` (HttpRequestErrorHandlingOptions): ReC request error handling
+
+#### `SqlQueryErrorHandlingOptions`
+Error handling for SQL query execution.
+
+**Properties:**
+- `OnExecution` (ErrorAction): Action when query execution fails (default: `Stop`)
+- `IfNullOrWhiteSpace` (ErrorAction): Action when query is null/empty (default: `Ignore`)
+- `OnUnexpectedResult` (ErrorAction): Action when result is unexpected (default: `Stop`)
+
+**Error Actions:**
+- `Ignore`: Continue execution
+- `Stop`: Throw `DEXJobException`
+
+#### `HttpRequestErrorHandlingOptions`
+Error handling for HTTP requests.
+
+**Properties:**
+- `OnSending` (ErrorAction): Action when HTTP request fails (default: `Stop`)
+
+#### `PlaceHolderOptions`
+Configuration for dynamic placeholder replacement.
+
+**Properties:**
+- `BatchId` (PlaceHolder): Batch ID placeholder configuration
+  - `Pattern` (string): Regex pattern (default: `#INT#BATCH_ID`)
+  - `RegexOptions` (RegexOptions): Regex options (default: `IgnoreCase`)
+
+### Expected Query Results
+
+#### Main Query (`SqlMainQuery`)
+**Expected Result:**
+- `ReturnValue` should be **null**
+- If not null: throws `DEXJobException` (when `OnUnexpectedResult` = `Stop`)
+
+**Example SQL:**
+```sql
+INSERT INTO TBJR_OUT_PROFILE_HISTORY (BatchId, ProfileId, CreatedAt)
+VALUES ('#INT#BATCH_ID', 123, GETDATE())
+```
+
+#### Check Query (`SqlCheckQuery`)
+**Expected Result:**
+- `ReturnValue` should be **> 0**
+- If ≤ 0: throws `DEXJobException` (when `OnUnexpectedResult` = `Stop`)
+
+**Example SQL:**
+```sql
+SELECT COUNT(*) AS [Return Value]
+FROM TBJR_OUT_PROFILE_HISTORY
+WHERE BatchId = '#INT#BATCH_ID'
+```
+
+### Placeholder Replacement
+
+The `#INT#BATCH_ID` placeholder in SQL queries is replaced with the actual batch ID using regex:
+
+**Before:**
+```sql
+INSERT INTO Table (BatchId) VALUES ('#INT#BATCH_ID')
+```
+
+**After:**
+```sql
+INSERT INTO Table (BatchId) VALUES ('20260711143025123456')
+```
+
+## Dependency Injection
+
+### Setup in Startup.cs / Program.cs
+
+```csharp
+using ECMJobRunner.Application;
+using ECMJobRunner.Application.Common.Options;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+// Add Application layer services
+services.AddApplication();
+
+// Configure DexJobOptions from appsettings.json
+services.Configure<DexJobOptions>(configuration.GetSection("DexJob"));
+
+// Register dependencies
+services.AddSingleton<ISQLExecutor, SqlExecutor>(); // Your implementation
+services.AddSingleton<ReCClient>(); // ReC client configuration
+```
+
+### Required Dependencies
+
+The following interfaces must be implemented in your Infrastructure layer:
+
+1. **`ISQLExecutor`**: SQL query execution and DTO mapping
+   ```csharp
+   public interface ISQLExecutor
+   {
+       Task<TResult?> ExecuteQueryAsync<TResult>(string sql, CancellationToken cancellationToken = default);
+   }
+   ```
+
+2. **`IProfileSqlJobRepository`**: Repository for ProfileSqlJob entities
+   ```csharp
+   public interface IProfileSqlJobRepository : IRepository
+   {
+       Task<IEnumerable<ProfileSqlJob>> FindAsync(Expression<Func<ProfileSqlJob, bool>> predicate, CancellationToken cancellationToken);
+   }
+   ```
+
+3. **`ReCClient`**: ReC HTTP client (from `ReC.Client` NuGet package)
+
+## Exception Handling
+
+### `DEXJobException`
+Custom exception thrown when DEX job operations fail.
+
+**Properties:**
+- `QueryName` (string): Name of the query that failed
+- `BatchId` (string): Batch ID associated with the operation
+- `SqlQuery` (string?): SQL query that was executed (nullable)
+- `Message` (string): Formatted error message with query details
+
+**Constructors:**
+1. With inner exception:
+   ```csharp
+   new DEXJobException("SQL Main Query", batchId, sqlQuery, innerException)
+   ```
+
+2. With reason message:
+   ```csharp
+   new DEXJobException("SQL Check Query", batchId, sqlQuery, "Check Query returned nothing.")
+   ```
+
+**Example Error Message:**
+```
+[SQL Execution Failure] Query 'SQL Main Query' could not be completed for Batch '20260711143025123456'.
+─────────────────────────────────────────
+  Query:
+    INSERT INTO Table (BatchId) VALUES ('#INT#BATCH_ID')
+
+  Root Cause:
+    Timeout expired. The timeout period elapsed prior to completion of the operation.
+─────────────────────────────────────────
+```
+
+## Multi-Targeting Support
+
+The project targets:
+- **.NET Framework 4.8** (`net480`) - MediatR 9.0.0
+- **.NET 8.0** (`net8.0`) - MediatR 12.4.1
+
+Pipeline behaviors use conditional compilation for MediatR signature differences:
+
+```csharp
+#if NET48
+public async Task<TResponse> Handle(TRequest request, CancellationToken cancellationToken, RequestHandlerDelegate<TResponse> next)
+#else
+public async Task<TResponse> Handle(TRequest request, RequestHandlerDelegate<TResponse> next, CancellationToken cancellationToken)
+#endif
+```
+
+## Testing
+
+Unit tests should mock:
+- `ISQLExecutor` - for SQL query execution
+- `IOptions<DexJobOptions>` - for configuration
+- `ReCClient` - for HTTP requests
+- `IProfileSqlJobRepository` - for data access
+
+**Example test structure:**
+```csharp
+[Fact]
+public async Task Handle_WithValidBatchCommand_ExecutesAllJobs()
+{
+    // Arrange
+    var mockRepo = new Mock<IProfileSqlJobRepository>();
+    var mockSender = new Mock<ISender>();
+    mockRepo.Setup(r => r.FindAsync(It.IsAny<Expression<Func<ProfileSqlJob, bool>>>(), It.IsAny<CancellationToken>()))
+            .ReturnsAsync(new List<ProfileSqlJob> { job1, job2 });
+
+    var handler = new TriggeringDEXJobBatchCommandHandler(mockRepo.Object, mockSender.Object);
+    var command = new TriggeringDEXJobBatchCommand { ProfileId = 123 };
+
+    // Act
+    await handler.Handle(command, CancellationToken.None);
+
+    // Assert
+    mockSender.Verify(s => s.Send(It.IsAny<TriggeringDEXJobCommand>(), It.IsAny<CancellationToken>()), Times.Exactly(2));
+}
+```
+
+## Batch ID Format
+
+Batch IDs are 20-character timestamp strings:
+
+**Format:** `yyyyMMddHHmmssfffffff` (truncated to 20 chars)
+
+**Example:** `20260711143025123456`
+
+**Components:**
+- `yyyy`: Year (4 digits)
+- `MM`: Month (2 digits)
+- `dd`: Day (2 digits)
+- `HH`: Hour - 24-hour format (2 digits)
+- `mm`: Minute (2 digits)
+- `ss`: Second (2 digits)
+- `fffffff`: Fractions of a second / 100-nanoseconds (7 digits) - truncated to 6 digits
+
+## Troubleshooting
+
+### Common Issues
+
+#### 1. "Main Query returned nothing"
+**Cause:** Main query execution did not return any result.  
+**Solution:** Check if SQL query is valid and returns expected structure with `[Return Value]` column.
+
+#### 2. "The query unexpectedly returned the value X. The expected value was null."
+**Cause:** Main query returned non-null value indicating an error.  
+**Solution:** Check SQL query logic and ensure it returns NULL on success.
+
+#### 3. "Check Query returned nothing"
+**Cause:** Check query did not return any result.  
+**Solution:** Verify check query syntax and ensure it returns a `[Return Value]` column.
+
+#### 4. "The query unexpectedly returned the value X. The expected value was any value greater than 0."
+**Cause:** Check query returned ≤ 0 indicating validation failure.  
+**Solution:** Verify main query executed successfully and check query logic is correct.
+
+#### 5. "SQL Main Query is null or empty"
+**Cause:** `SqlMainQuery` property is null or whitespace.  
+**Solution:** Set `Error.MainQuery.IfNullOrWhiteSpace = Ignore` in configuration if optional.
+
+### Debug Configuration
+
+For detailed error information, set all error actions to `Stop`:
+
+```json
+{
+  "DexJob": {
+    "Error": {
+      "MainQuery": {
+        "OnExecution": "Stop",
+        "IfNullOrWhiteSpace": "Stop",
+        "OnUnexpectedResult": "Stop"
+      },
+      "CheckQuery": {
+        "OnExecution": "Stop",
+        "IfNullOrWhiteSpace": "Stop",
+        "OnUnexpectedResult": "Stop"
+      },
+      "ReCRequest": {
+        "OnSending": "Stop"
+      }
+    }
+  }
+}
+```
+
+## Company Information
+
+**Author:** Digital Data GmbH  
+**Copyright:** 2026  
+**Repository:** http://git.dd:3000/AppStd/ECMJobRunner.git