diff --git a/Bodies/NewDocumentBody.cs b/Bodies/NewDocumentBody.cs
deleted file mode 100644
index 1ed3c12..0000000
--- a/Bodies/NewDocumentBody.cs
+++ /dev/null
@@ -1,10 +0,0 @@
-using System;
-using Newtonsoft.Json;
-
-namespace PaperlessAI.Bodies;
-
-public class NewDocumentBody
-{
-    [JsonProperty("document_id")]
-    public int DocumentId { get; set; }
-}
diff --git a/Bodies/NewPaperlessDocumentBody.cs b/Bodies/NewPaperlessDocumentBody.cs
new file mode 100644
index 0000000..f9ee651
--- /dev/null
+++ b/Bodies/NewPaperlessDocumentBody.cs
@@ -0,0 +1,15 @@
+using System;
+using Newtonsoft.Json;
+
+namespace PaperlessAI.Bodies;
+
+public class NewPaperlessDocumentBody
+{
+    [JsonProperty("document_id")]
+    public long DocumentId { get; set; }
+
+    public override string ToString()
+    {
+        return JsonConvert.SerializeObject(this);
+    }
+}
diff --git a/Context/MyDbContext.cs b/Context/MyDbContext.cs
index a658568..9cbf38a 100644
--- a/Context/MyDbContext.cs
+++ b/Context/MyDbContext.cs
@@ -1,5 +1,5 @@
-using System;
 using Microsoft.EntityFrameworkCore;
+using PaperlessAI.Models;
 
 namespace PaperlessAI.Context;
 
@@ -19,6 +19,13 @@ public class MyDbContext : DbContext
         modelBuilder
             .UseCollation("utf8mb4_uca1400_ai_ci")
             .HasCharSet("utf8mb4");
+
+        modelBuilder
+            .Entity<PaperlessDocument>()
+            .HasIndex(x => x.DocumentId)
+            .IsUnique();
     }
 
+    public DbSet<PaperlessDocument> PaperlessDocuments { get; set; }
+
 }
diff --git a/Controllers/DocumentController.cs b/Controllers/DocumentController.cs
deleted file mode 100644
index e0d73e7..0000000
--- a/Controllers/DocumentController.cs
+++ /dev/null
@@ -1,17 +0,0 @@
-using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.Mvc;
-using PaperlessAI.Bodies;
-
-namespace PaperlessAI.Controllers
-{
-    [Route("[controller]")]
-    [ApiController]
-    public class DocumentController : ControllerBase
-    {
-        [HttpPost]
-        public ActionResult AddNewDocument([FromBody]NewDocumentBody newDocument)
-        {
-            return Ok();
-        }
-    }
-}
diff --git a/Controllers/PaperlessDocumentController.cs b/Controllers/PaperlessDocumentController.cs
new file mode 100644
index 0000000..01d6bb7
--- /dev/null
+++ b/Controllers/PaperlessDocumentController.cs
@@ -0,0 +1,37 @@
+using Microsoft.AspNetCore.Mvc;
+using PaperlessAI.Bodies;
+using PaperlessAI.Services;
+
+namespace PaperlessAI.Controllers
+{
+    [Route("Document")]
+    [ApiController]
+    public class PaperlessDocumentController(PaperlessDocumentService documentService, ILogger<PaperlessDocumentController> logger) : ControllerBase
+    {
+        [HttpPost]
+        public async Task<ActionResult> AddNewDocument([FromBody]NewPaperlessDocumentBody newPaperlessDocumentBody)
+        {
+            logger.LogDebug($"AddNewDocument called with body: {newPaperlessDocumentBody}");
+
+            try
+            {
+                if(await documentService.Exists(newPaperlessDocumentBody.DocumentId))
+                {
+                    logger.LogWarning($"Document {newPaperlessDocumentBody.DocumentId} already exists.");
+                    return Conflict();
+                }
+
+                await documentService.Create(newPaperlessDocumentBody.DocumentId);
+                logger.LogWarning($"Document {newPaperlessDocumentBody.DocumentId} created.");
+            }
+            catch (Exception e)
+            {
+                logger.LogError(e.ToString());
+                return StatusCode(500);
+            }
+
+            logger.LogDebug($"AddNewDocument Ok!");
+            return Ok();
+        }
+    }
+}
diff --git a/Enums/EOperationState.cs b/Enums/EOperationState.cs
new file mode 100644
index 0000000..6f1807f
--- /dev/null
+++ b/Enums/EOperationState.cs
@@ -0,0 +1,10 @@
+namespace PaperlessAI.Enums;
+
+public enum EOperationState
+{
+    Created = 0,
+    Queued = 1,
+    Started = 2,
+    Success = 3,
+    Failed = 4
+}
diff --git a/Interfaces/IRepository.cs b/Interfaces/IRepository.cs
new file mode 100644
index 0000000..8addd73
--- /dev/null
+++ b/Interfaces/IRepository.cs
@@ -0,0 +1,11 @@
+namespace PaperlessAI.Interfaces;
+
+public interface IRepository<T>
+{
+    Task Add(T model, bool persist = true);
+    Task Remove(T model, bool persist = true);
+    Task Update(T model, bool persist = true);
+    Task<T?> Get(long id);
+    Task<List<T>> GetAll();
+    
+}
diff --git a/Migrations/20261009132858_Init.Designer.cs b/Migrations/20261009132858_Init.Designer.cs
new file mode 100644
index 0000000..8a727ed
--- /dev/null
+++ b/Migrations/20261009132858_Init.Designer.cs
@@ -0,0 +1,60 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using PaperlessAI.Context;
+
+#nullable disable
+
+namespace PaperlessAI.Migrations
+{
+    [DbContext(typeof(MyDbContext))]
+    [Migration("20261009132858_Init")]
+    partial class Init
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .UseCollation("utf8mb4_uca1400_ai_ci")
+                .HasAnnotation("ProductVersion", "10.0.12")
+                .HasAnnotation("Relational:MaxIdentifierLength", 64);
+
+            MySqlModelBuilderExtensions.HasCharSet(modelBuilder, "utf8mb4");
+            MySqlModelBuilderExtensions.AutoIncrementColumns(modelBuilder);
+
+            modelBuilder.Entity("PaperlessAI.Models.PaperlessDocument", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    MySqlPropertyBuilderExtensions.UseMySqlIdentityColumn(b.Property<long>("Id"));
+
+                    b.Property<DateTimeOffset>("CreatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.Property<long>("DocumentId")
+                        .HasColumnType("bigint");
+
+                    b.Property<int>("DocumentState")
+                        .HasColumnType("int");
+
+                    b.Property<DateTimeOffset>("ModifiedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("DocumentId")
+                        .IsUnique();
+
+                    b.ToTable("PaperlessDocuments");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/Migrations/20261009132858_Init.cs b/Migrations/20261009132858_Init.cs
new file mode 100644
index 0000000..2d9486a
--- /dev/null
+++ b/Migrations/20261009132858_Init.cs
@@ -0,0 +1,50 @@
+using System;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace PaperlessAI.Migrations
+{
+    /// <inheritdoc />
+    public partial class Init : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterDatabase()
+                .Annotation("MySql:CharSet", "utf8mb4");
+
+            migrationBuilder.CreateTable(
+                name: "PaperlessDocuments",
+                columns: table => new
+                {
+                    Id = table.Column<long>(type: "bigint", nullable: false)
+                        .Annotation("MySql:ValueGenerationStrategy", MySqlValueGenerationStrategy.IdentityColumn),
+                    DocumentId = table.Column<long>(type: "bigint", nullable: false),
+                    DocumentState = table.Column<int>(type: "int", nullable: false),
+                    CreatedAt = table.Column<DateTimeOffset>(type: "datetime(6)", nullable: false),
+                    ModifiedAt = table.Column<DateTimeOffset>(type: "datetime(6)", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_PaperlessDocuments", x => x.Id);
+                })
+                .Annotation("MySql:CharSet", "utf8mb4")
+                .Annotation("Relational:Collation", "utf8mb4_uca1400_ai_ci");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_PaperlessDocuments_DocumentId",
+                table: "PaperlessDocuments",
+                column: "DocumentId",
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "PaperlessDocuments");
+        }
+    }
+}
diff --git a/Migrations/MyDbContextModelSnapshot.cs b/Migrations/MyDbContextModelSnapshot.cs
new file mode 100644
index 0000000..35a9c56
--- /dev/null
+++ b/Migrations/MyDbContextModelSnapshot.cs
@@ -0,0 +1,57 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using PaperlessAI.Context;
+
+#nullable disable
+
+namespace PaperlessAI.Migrations
+{
+    [DbContext(typeof(MyDbContext))]
+    partial class MyDbContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .UseCollation("utf8mb4_uca1400_ai_ci")
+                .HasAnnotation("ProductVersion", "10.0.12")
+                .HasAnnotation("Relational:MaxIdentifierLength", 64);
+
+            MySqlModelBuilderExtensions.HasCharSet(modelBuilder, "utf8mb4");
+            MySqlModelBuilderExtensions.AutoIncrementColumns(modelBuilder);
+
+            modelBuilder.Entity("PaperlessAI.Models.PaperlessDocument", b =>
+                {
+                    b.Property<long>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("bigint");
+
+                    MySqlPropertyBuilderExtensions.UseMySqlIdentityColumn(b.Property<long>("Id"));
+
+                    b.Property<DateTimeOffset>("CreatedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.Property<long>("DocumentId")
+                        .HasColumnType("bigint");
+
+                    b.Property<int>("DocumentState")
+                        .HasColumnType("int");
+
+                    b.Property<DateTimeOffset>("ModifiedAt")
+                        .HasColumnType("datetime(6)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("DocumentId")
+                        .IsUnique();
+
+                    b.ToTable("PaperlessDocuments");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}
diff --git a/Models/PaperlessDocument.cs b/Models/PaperlessDocument.cs
new file mode 100644
index 0000000..84b5d82
--- /dev/null
+++ b/Models/PaperlessDocument.cs
@@ -0,0 +1,24 @@
+using PaperlessAI.Enums;
+
+namespace PaperlessAI.Models;
+
+public class PaperlessDocument
+{
+    public long Id { get; set; }
+    public long DocumentId { get; set; }
+    public EOperationState DocumentState { get; set; } = EOperationState.Created;
+    public DateTimeOffset CreatedAt { get; set; } = DateTime.UtcNow;
+    public DateTimeOffset ModifiedAt { get; set; } = DateTime.UtcNow;
+
+    public PaperlessDocument(long documentId)
+    {
+        DocumentId = documentId;
+    }
+
+    public static PaperlessDocument Create(long documentId)
+    {
+        var paperlessDocument = new PaperlessDocument(documentId);
+        return paperlessDocument;
+    }
+
+}
diff --git a/PaperlessAI.csproj b/PaperlessAI.csproj
index d6f3d5d..cad8cdd 100644
--- a/PaperlessAI.csproj
+++ b/PaperlessAI.csproj
@@ -11,7 +11,9 @@
     <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.12" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="10.0.12" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.4" />
-    <PackageReference Include="Pomelo.EntityFrameworkCore.MySql" Version="9.0.0" />
+    <PackageReference Include="Microting.EntityFrameworkCore.MySql" Version="10.0.12" />
+    <PackageReference Include="Serilog.AspNetCore" Version="10.0.0" />
+    <PackageReference Include="Serilog.Sinks.File" Version="7.0.0" />
   </ItemGroup>
 
 </Project>
diff --git a/Program.cs b/Program.cs
index 391135f..ebbbdd1 100644
--- a/Program.cs
+++ b/Program.cs
@@ -1,28 +1,49 @@
 using Microsoft.EntityFrameworkCore;
 using PaperlessAI.Context;
+using PaperlessAI.Repositories;
+using PaperlessAI.Services;
+using Serilog;
 
 var builder = WebApplication.CreateBuilder(args);
 
-// Add services to the container.
+// Services
+builder.Services.AddScoped<PaperlessDocumentService>();
 
+// Repositories
+builder.Services.AddScoped<PaperlessDocumentRepository>();
+
+// Other
 builder.Services.AddControllers();
 
+// Database
 builder.Services.AddDbContextPool<MyDbContext>(options =>
 {
     options.UseMySql(
         builder.Configuration.GetConnectionString("MariaDbConnectionString"),
         ServerVersion.Parse("12.0.2-mariadb")
-    );
+    )
+    .LogTo(Console.WriteLine, LogLevel.Information)
+    .EnableSensitiveDataLogging()
+    .EnableDetailedErrors();
 });
 
+// Logging
+Log.Logger = new LoggerConfiguration()
+    .MinimumLevel.Debug()
+    .WriteTo.Console()
+    .WriteTo.File(
+        Path.Combine(AppContext.BaseDirectory, "logs", "log-.txt"), 
+        rollingInterval: RollingInterval.Day,
+        retainedFileCountLimit: 30)
+    .CreateLogger();
+
+builder.Host.UseSerilog();
+
+// App
 var app = builder.Build();
 
 // Configure the HTTP request pipeline.
-
 app.UseHttpsRedirection();
-
 app.UseAuthorization();
-
 app.MapControllers();
-
 app.Run();
diff --git a/Properties/launchSettings.json b/Properties/launchSettings.json
index 6aedc56..81f63eb 100644
--- a/Properties/launchSettings.json
+++ b/Properties/launchSettings.json
@@ -10,14 +10,5 @@
         "ASPNETCORE_ENVIRONMENT": "Development"
       }
     },
-    "https": {
-      "commandName": "Project",
-      "dotnetRunMessages": true,
-      "launchBrowser": false,
-      "applicationUrl": "https://localhost:7245;http://localhost:5276",
-      "environmentVariables": {
-        "ASPNETCORE_ENVIRONMENT": "Development"
-      }
-    }
   }
 }
diff --git a/Repositories/DocumentRepository.cs b/Repositories/DocumentRepository.cs
new file mode 100644
index 0000000..7718912
--- /dev/null
+++ b/Repositories/DocumentRepository.cs
@@ -0,0 +1,38 @@
+using Microsoft.EntityFrameworkCore;
+using PaperlessAI.Context;
+using PaperlessAI.Interfaces;
+using PaperlessAI.Models;
+
+namespace PaperlessAI.Repositories;
+
+public class PaperlessDocumentRepository(MyDbContext context) : IRepository<PaperlessDocument>
+{
+    public async Task Add(PaperlessDocument model, bool persist = true)
+    {
+        await context.PaperlessDocuments.AddAsync(model);
+        await SaveOnPersist(persist);
+    }
+
+    public async Task Remove(PaperlessDocument model, bool persist = true)
+    {
+        context.PaperlessDocuments.Remove(model);
+        await SaveOnPersist(persist);
+    }
+
+    public async Task Update(PaperlessDocument model, bool persist = true)
+    {
+        context.PaperlessDocuments.Update(model);
+        await SaveOnPersist(persist);
+    }
+
+    public async Task<PaperlessDocument?> Get(long id) => await context.PaperlessDocuments.Where(x => x.DocumentId == id).FirstOrDefaultAsync();
+    public async Task<List<PaperlessDocument>> GetAll() => await context.PaperlessDocuments.ToListAsync();
+
+    public async Task SaveOnPersist(bool persist)
+    {
+        if(persist)
+        {
+            await context.SaveChangesAsync();
+        }
+    }
+}
diff --git a/Services/DocumentService.cs b/Services/DocumentService.cs
new file mode 100644
index 0000000..a752b8a
--- /dev/null
+++ b/Services/DocumentService.cs
@@ -0,0 +1,22 @@
+using PaperlessAI.Models;
+using PaperlessAI.Repositories;
+
+namespace PaperlessAI.Services;
+
+public class PaperlessDocumentService(PaperlessDocumentRepository docRepo)
+{
+    public async Task<bool> Exists(long documentId)
+    {
+        if(documentId < 0 || documentId > long.MaxValue)
+            throw new Exception($"Value \"{documentId}\" must be in Range between 0 - {long.MaxValue}!");
+        
+        return await docRepo.Get(documentId) != null;
+    }
+
+    public async Task<PaperlessDocument> Create(long documentId)
+    {
+        var doc = PaperlessDocument.Create(documentId);
+        await docRepo.Add(doc);
+        return doc;
+    }
+}
diff --git a/api.http b/api.http
new file mode 100644
index 0000000..1ddee66
--- /dev/null
+++ b/api.http
@@ -0,0 +1,6 @@
+POST http://localhost:5276/Document HTTP/1.1
+Content-Type: application/json
+
+{
+    "document_id": 8
+}
\ No newline at end of file