diff --git a/DysonNetwork.Develop/AppDatabase.cs b/DysonNetwork.Develop/AppDatabase.cs
index 13b9e9b..29aff8a 100644
--- a/DysonNetwork.Develop/AppDatabase.cs
+++ b/DysonNetwork.Develop/AppDatabase.cs
@@ -1,3 +1,4 @@
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Design;
@@ -33,36 +34,15 @@ public class AppDatabase(
     
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
         base.OnModelCreating(modelBuilder);
+        
+        modelBuilder.ApplySoftDeleteFilters();
     }
 }
 
diff --git a/DysonNetwork.Drive/AppDatabase.cs b/DysonNetwork.Drive/AppDatabase.cs
index 2bb530d..85eded4 100644
--- a/DysonNetwork.Drive/AppDatabase.cs
+++ b/DysonNetwork.Drive/AppDatabase.cs
@@ -1,8 +1,8 @@
 using System.Linq.Expressions;
-using System.Reflection;
 using DysonNetwork.Drive.Billing;
 using DysonNetwork.Drive.Storage;
 using DysonNetwork.Drive.Storage.Model;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Design;
@@ -46,67 +46,12 @@ public class AppDatabase(
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
         base.OnModelCreating(modelBuilder);
-
-        // Apply soft-delete filter only to root entities, not derived types
-        var entityTypes = modelBuilder.Model.GetEntityTypes();
-        foreach (var entityType in entityTypes)
-        {
-            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
-
-            // Skip derived types to avoid filter conflicts
-            var clrType = entityType.ClrType;
-            if (clrType.BaseType != typeof(ModelBase) && 
-                typeof(ModelBase).IsAssignableFrom(clrType.BaseType))
-            {
-                continue; // Skip derived types
-            }
-
-            // Apply soft delete filter using cached reflection
-            ApplySoftDeleteFilter(modelBuilder, clrType);
-        }
-    }
-
-    private static readonly MethodInfo SetSoftDeleteFilterMethod = typeof(AppDatabase)
-        .GetMethod(nameof(SetSoftDeleteFilter), BindingFlags.NonPublic | BindingFlags.Static)!;
-
-    private static void ApplySoftDeleteFilter(ModelBuilder modelBuilder, Type entityType)
-    {
-        var genericMethod = SetSoftDeleteFilterMethod.MakeGenericMethod(entityType);
-        genericMethod.Invoke(null, [modelBuilder]);
-    }
-
-    private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
-        where TEntity : ModelBase
-    {
-        modelBuilder.Entity<TEntity>().HasQueryFilter(e => e.DeletedAt == null);
+        modelBuilder.ApplySoftDeleteFilters();
     }
 
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 }
@@ -210,35 +155,3 @@ public class AppDatabaseFactory : IDesignTimeDbContextFactory<AppDatabase>
         return new AppDatabase(optionsBuilder.Options, configuration);
     }
 }
-
-public static class OptionalQueryExtensions
-{
-    public static IQueryable<T> If<T>(
-        this IQueryable<T> source,
-        bool condition,
-        Func<IQueryable<T>, IQueryable<T>> transform
-    )
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, TP> source,
-        bool condition,
-        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, IEnumerable<TP>> source,
-        bool condition,
-        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-}
diff --git a/DysonNetwork.Drive/Storage/FileReferenceService.cs b/DysonNetwork.Drive/Storage/FileReferenceService.cs
index 258ed65..ae6a53c 100644
--- a/DysonNetwork.Drive/Storage/FileReferenceService.cs
+++ b/DysonNetwork.Drive/Storage/FileReferenceService.cs
@@ -1,4 +1,5 @@
 using DysonNetwork.Shared.Cache;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using EFCore.BulkExtensions;
 using Microsoft.EntityFrameworkCore;
diff --git a/DysonNetwork.Insight/AppDatabase.cs b/DysonNetwork.Insight/AppDatabase.cs
index 5f7d3b0..79063f2 100644
--- a/DysonNetwork.Insight/AppDatabase.cs
+++ b/DysonNetwork.Insight/AppDatabase.cs
@@ -1,3 +1,4 @@
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Design;
@@ -29,36 +30,15 @@ public class AppDatabase(
     
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 
     protected override void OnModelCreating(ModelBuilder modelBuilder)
     {
         base.OnModelCreating(modelBuilder);
+        
+        modelBuilder.ApplySoftDeleteFilters();
     }
 }
 
diff --git a/DysonNetwork.Pass/AppDatabase.cs b/DysonNetwork.Pass/AppDatabase.cs
index 10a4c43..f846d1f 100644
--- a/DysonNetwork.Pass/AppDatabase.cs
+++ b/DysonNetwork.Pass/AppDatabase.cs
@@ -1,8 +1,8 @@
 using System.Linq.Expressions;
-using System.Reflection;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using DysonNetwork.Pass.Permission;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Design;
@@ -143,51 +143,12 @@ public class AppDatabase(
             .HasForeignKey(pm => pm.RealmId)
             .OnDelete(DeleteBehavior.Cascade);
 
-        // Automatically apply soft-delete filter to all entities inheriting BaseModel
-        foreach (var entityType in modelBuilder.Model.GetEntityTypes())
-        {
-            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
-            var method = typeof(AppDatabase)
-                .GetMethod(nameof(SetSoftDeleteFilter),
-                    BindingFlags.NonPublic | BindingFlags.Static)!
-                .MakeGenericMethod(entityType.ClrType);
-
-            method.Invoke(null, [modelBuilder]);
-        }
-    }
-
-    private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
-        where TEntity : ModelBase
-    {
-        modelBuilder.Entity<TEntity>().HasQueryFilter(e => e.DeletedAt == null);
+        modelBuilder.ApplySoftDeleteFilters();
     }
 
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 }
@@ -266,34 +227,3 @@ public class AppDatabaseFactory : IDesignTimeDbContextFactory<AppDatabase>
     }
 }
 
-public static class OptionalQueryExtensions
-{
-    public static IQueryable<T> If<T>(
-        this IQueryable<T> source,
-        bool condition,
-        Func<IQueryable<T>, IQueryable<T>> transform
-    )
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, TP> source,
-        bool condition,
-        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, IEnumerable<TP>> source,
-        bool condition,
-        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-}
diff --git a/DysonNetwork.Ring/AppDatabase.cs b/DysonNetwork.Ring/AppDatabase.cs
index 8947473..338f334 100644
--- a/DysonNetwork.Ring/AppDatabase.cs
+++ b/DysonNetwork.Ring/AppDatabase.cs
@@ -1,5 +1,5 @@
 using System.Linq.Expressions;
-using System.Reflection;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Design;
@@ -34,51 +34,12 @@ public class AppDatabase(
     {
         base.OnModelCreating(modelBuilder);
 
-        // Automatically apply soft-delete filter to all entities inheriting BaseModel
-        foreach (var entityType in modelBuilder.Model.GetEntityTypes())
-        {
-            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
-            var method = typeof(AppDatabase)
-                .GetMethod(nameof(SetSoftDeleteFilter),
-                    BindingFlags.NonPublic | BindingFlags.Static)!
-                .MakeGenericMethod(entityType.ClrType);
-
-            method.Invoke(null, [modelBuilder]);
-        }
-    }
-
-    private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
-        where TEntity : ModelBase
-    {
-        modelBuilder.Entity<TEntity>().HasQueryFilter(e => e.DeletedAt == null);
+        modelBuilder.ApplySoftDeleteFilters();
     }
 
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 }
@@ -143,35 +104,3 @@ public class AppDatabaseFactory : IDesignTimeDbContextFactory<AppDatabase>
         return new AppDatabase(optionsBuilder.Options, configuration);
     }
 }
-
-public static class OptionalQueryExtensions
-{
-    public static IQueryable<T> If<T>(
-        this IQueryable<T> source,
-        bool condition,
-        Func<IQueryable<T>, IQueryable<T>> transform
-    )
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, TP> source,
-        bool condition,
-        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, IEnumerable<TP>> source,
-        bool condition,
-        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-}
diff --git a/DysonNetwork.Shared/Data/OptionalQueryExtension.cs b/DysonNetwork.Shared/Data/OptionalQueryExtension.cs
new file mode 100644
index 0000000..0fd541a
--- /dev/null
+++ b/DysonNetwork.Shared/Data/OptionalQueryExtension.cs
@@ -0,0 +1,35 @@
+using Microsoft.EntityFrameworkCore.Query;
+
+namespace DysonNetwork.Shared.Data;
+
+public static class OptionalQueryExtensions
+{
+    public static IQueryable<T> If<T>(
+        this IQueryable<T> source,
+        bool condition,
+        Func<IQueryable<T>, IQueryable<T>> transform
+    )
+    {
+        return condition ? transform(source) : source;
+    }
+
+    public static IQueryable<T> If<T, TP>(
+        this IIncludableQueryable<T, TP> source,
+        bool condition,
+        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
+    )
+        where T : class
+    {
+        return condition ? transform(source) : source;
+    }
+
+    public static IQueryable<T> If<T, TP>(
+        this IIncludableQueryable<T, IEnumerable<TP>> source,
+        bool condition,
+        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
+    )
+        where T : class
+    {
+        return condition ? transform(source) : source;
+    }
+}
\ No newline at end of file
diff --git a/DysonNetwork.Shared/Data/SoftDeleteExtension.cs b/DysonNetwork.Shared/Data/SoftDeleteExtension.cs
new file mode 100644
index 0000000..ad9de32
--- /dev/null
+++ b/DysonNetwork.Shared/Data/SoftDeleteExtension.cs
@@ -0,0 +1,65 @@
+using System.Reflection;
+using DysonNetwork.Shared.Models;
+using Microsoft.EntityFrameworkCore;
+using NodaTime;
+
+namespace DysonNetwork.Shared.Data;
+
+public static class SoftDeleteExtension
+{
+    public static void ApplySoftDeleteFilters(this ModelBuilder modelBuilder)
+    {
+        var entityTypes = modelBuilder.Model.GetEntityTypes();
+        foreach (var entityType in entityTypes)
+        {
+            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
+
+            // Skip derived types to avoid filter conflicts
+            var clrType = entityType.ClrType;
+            if (clrType.BaseType != typeof(ModelBase) && 
+                typeof(ModelBase).IsAssignableFrom(clrType.BaseType))
+            {
+                continue; // Skip derived types
+            }
+
+            // Apply soft delete filter using cached reflection
+            var method = typeof(SoftDeleteExtension)
+                .GetMethod(nameof(SetSoftDeleteFilter), BindingFlags.NonPublic | BindingFlags.Static)!
+                .MakeGenericMethod(entityType.ClrType);
+            method.Invoke(null, new object[] { modelBuilder });
+        }
+    }
+
+    private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
+        where TEntity : ModelBase
+    {
+        modelBuilder.Entity<TEntity>().HasQueryFilter(e => e.DeletedAt == null);
+    }
+
+    public static void ApplyAuditableAndSoftDelete(this DbContext context)
+    {
+        var now = SystemClock.Instance.GetCurrentInstant();
+
+        foreach (var entry in context.ChangeTracker.Entries<ModelBase>())
+        {
+            switch (entry.State)
+            {
+                case EntityState.Added:
+                    entry.Entity.CreatedAt = now;
+                    entry.Entity.UpdatedAt = now;
+                    break;
+                case EntityState.Modified:
+                    entry.Entity.UpdatedAt = now;
+                    break;
+                case EntityState.Deleted:
+                    entry.State = EntityState.Modified;
+                    entry.Entity.DeletedAt = now;
+                    break;
+                case EntityState.Detached:
+                case EntityState.Unchanged:
+                default:
+                    break;
+            }
+        }
+    }
+}
diff --git a/DysonNetwork.Sphere/AppDatabase.cs b/DysonNetwork.Sphere/AppDatabase.cs
index a1c74c7..5096a15 100644
--- a/DysonNetwork.Sphere/AppDatabase.cs
+++ b/DysonNetwork.Sphere/AppDatabase.cs
@@ -1,5 +1,5 @@
 using System.Linq.Expressions;
-using System.Reflection;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using DysonNetwork.Sphere.WebReader;
 using Microsoft.EntityFrameworkCore;
@@ -142,17 +142,7 @@ public class AppDatabase(
             .HasIndex(a => a.Url)
             .IsUnique();
 
-        // Automatically apply soft-delete filter to all entities inheriting BaseModel
-        foreach (var entityType in modelBuilder.Model.GetEntityTypes())
-        {
-            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
-            var method = typeof(AppDatabase)
-                .GetMethod(nameof(SetSoftDeleteFilter),
-                    BindingFlags.NonPublic | BindingFlags.Static)!
-                .MakeGenericMethod(entityType.ClrType);
-
-            method.Invoke(null, [modelBuilder]);
-        }
+        modelBuilder.ApplySoftDeleteFilters();
     }
 
     private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
@@ -163,30 +153,7 @@ public class AppDatabase(
 
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 }
@@ -252,34 +219,3 @@ public class AppDatabaseFactory : IDesignTimeDbContextFactory<AppDatabase>
     }
 }
 
-public static class OptionalQueryExtensions
-{
-    public static IQueryable<T> If<T>(
-        this IQueryable<T> source,
-        bool condition,
-        Func<IQueryable<T>, IQueryable<T>> transform
-    )
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, TP> source,
-        bool condition,
-        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, IEnumerable<TP>> source,
-        bool condition,
-        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-}