diff --git a/DbFirst.API/Program.cs b/DbFirst.API/Program.cs
index c406c41..aea4bfd 100644
--- a/DbFirst.API/Program.cs
+++ b/DbFirst.API/Program.cs
@@ -4,6 +4,8 @@ using DbFirst.Infrastructure;
 using DbFirst.Infrastructure.Repositories;
 using Microsoft.EntityFrameworkCore;
 
+//TODO: create and add exception handling middleware
+
 var builder = WebApplication.CreateBuilder(args);
 
 // Add services to the container.
diff --git a/DbFirst.Application/Catalogs/CatalogService.cs b/DbFirst.Application/Catalogs/CatalogService.cs
index c2263da..03bcf8e 100644
--- a/DbFirst.Application/Catalogs/CatalogService.cs
+++ b/DbFirst.Application/Catalogs/CatalogService.cs
@@ -4,6 +4,8 @@ using DbFirst.Domain.Entities;
 
 namespace DbFirst.Application.Catalogs;
 
+//TODO: create generic service to reduce code duplication
+//TODO: implement CQRS pattern with MediatR
 public class CatalogService : ICatalogService
 {
     private readonly ICatalogRepository _repository;
diff --git a/DbFirst.Application/Catalogs/ICatalogService.cs b/DbFirst.Application/Catalogs/ICatalogService.cs
index f7bc50f..47538fb 100644
--- a/DbFirst.Application/Catalogs/ICatalogService.cs
+++ b/DbFirst.Application/Catalogs/ICatalogService.cs
@@ -1,5 +1,6 @@
 namespace DbFirst.Application.Catalogs;
 
+//TODO: create generic service to reduce code duplication
 public interface ICatalogService
 {
     Task<List<CatalogReadDto>> GetAllAsync(CancellationToken cancellationToken = default);