diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index bd97492..c87e81a 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -7,7 +7,7 @@ on:
     branches: [ main ]
     
 env:
-  VERSION: 3.2.${{ github.run_number }}
+  VERSION: 4.0.${{ github.run_number }}
   NUGET_INDEX: https://api.nuget.org/v3/index.json
   BUILD_TYPE: Release 
 
@@ -33,10 +33,14 @@ jobs:
     - name: Build
       run: dotnet build --no-restore --configuration Release -p:PackageVersion=${{env.VERSION}}
       
-    - name: Test
+    - name: Unit Tests
       run: dotnet test ./tests/**/*.UnitTests.csproj --no-restore
+      
+    - name: Integrated Tests
+      run: dotnet test ./tests/**/*.IntegratedTests.csproj --no-restore      
 
     - name: Publish Artifact
+      if: github.ref == 'refs/heads/main'
       run: |
         dotnet pack --no-restore --configuration ${{ env.BUILD_TYPE }} -p:PackageVersion=${{ env.VERSION }}
         dotnet nuget push ./src/**/*.${{ env.VERSION }}.nupkg --api-key ${{ secrets.NUGET_KEY }} --source ${{ env.NUGET_INDEX }}
diff --git a/README.md b/README.md
index b080982..3bc3812 100644
--- a/README.md
+++ b/README.md
@@ -29,9 +29,8 @@ dotnet add package C4Sharp
 ### Dependencies
 
 You need these things to run C4Sharp:
- - [.NET Standard 2.1](https://docs.microsoft.com/pt-br/dotnet/standard/net-standard)
+ - [.NET 5.0+](https://docs.microsoft.com/pt-br/dotnet/standard/net-standard)
  - [Java](https://www.java.com/en/download/)
- - [Graphviz](https://plantuml.com/graphviz-dot) 
 
 ### Coding
 
diff --git a/samples/C4Sharp.Sample.Orders/Program.cs b/samples/C4Sharp.Sample.Orders/Program.cs
index 80c4dc8..ae2e6e9 100644
--- a/samples/C4Sharp.Sample.Orders/Program.cs
+++ b/samples/C4Sharp.Sample.Orders/Program.cs
@@ -1,11 +1,11 @@
 using C4Sharp.Diagrams;
-using C4Sharp.Models.Plantuml;
+using C4Sharp.Models.Plantuml.IO;
 
 namespace C4Sharp.Sample.Orders
 {
     internal static class Program
     {
-        private static void Main(string[] args)
+        private static void Main()
         {
             var diagrams = new Diagram[]
             {
diff --git a/samples/C4Sharp.Sample/Program.cs b/samples/C4Sharp.Sample/Program.cs
index 6a587c6..5532a0c 100644
--- a/samples/C4Sharp.Sample/Program.cs
+++ b/samples/C4Sharp.Sample/Program.cs
@@ -1,13 +1,12 @@
 using C4Sharp.Diagrams;
-using C4Sharp.Models;
-using C4Sharp.Models.Plantuml;
+using C4Sharp.Models.Plantuml.IO;
 using C4Sharp.Sample.Diagrams;
 
 namespace C4Sharp.Sample
 {
     internal static class Program
     {
-        private static void Main(string[] args)
+        private static void Main()
         {
             var diagrams = new Diagram[]
             {
diff --git a/src/C4Sharp/C4Sharp.csproj b/src/C4Sharp/C4Sharp.csproj
index beba49d..1ddd04b 100644
--- a/src/C4Sharp/C4Sharp.csproj
+++ b/src/C4Sharp/C4Sharp.csproj
@@ -11,12 +11,13 @@
         <RepositoryUrl>https://github.com/8T4/c4sharp</RepositoryUrl>
         <RepositoryType>git</RepositoryType>
         <PackageTags>c4, diagrams</PackageTags>
-        <PackageVersion>3.2.0</PackageVersion>
+        <PackageVersion>4.0.0</PackageVersion>
         <PackageIconUrl>https://github.com/8T4/c4sharp/blob/main/LICENSE</PackageIconUrl>
         <PublishRepositoryUrl>true</PublishRepositoryUrl>
         <IncludeSymbols>true</IncludeSymbols>
         <SymbolPackageFormat>snupkg</SymbolPackageFormat>
         <LangVersion>9</LangVersion>
+        <Nullable>enable</Nullable>
     </PropertyGroup>
 
     <ItemGroup>
@@ -34,8 +35,8 @@
     <ItemGroup>
         <None Remove="Resources\*.puml" />
         <None Remove="Resources\plantuml.jar" />
-        
+
         <EmbeddedResource Include="Resources\*.puml" />
-        <EmbeddedResource Include="Resources\plantuml.jar" />        
+        <EmbeddedResource Include="Resources\plantuml.jar" />
     </ItemGroup>
 </Project>
diff --git a/src/C4Sharp/Diagrams/Diagram.cs b/src/C4Sharp/Diagrams/Diagram.cs
index 6e268cc..019312a 100644
--- a/src/C4Sharp/Diagrams/Diagram.cs
+++ b/src/C4Sharp/Diagrams/Diagram.cs
@@ -15,7 +15,7 @@ public abstract record Diagram
         public bool LayoutWithLegend { get; set; }
         public bool ShowLegend { get; set; }
         public bool LayoutAsSketch { get; set; }
-        public string Title { get; set; }
+        public string? Title { get; set; }
         public DiagramLayout FlowVisualization { get; set; }
         public Structure[] Structures { get; set; }
         public Relationship[] Relationships { get; set; }
diff --git a/src/C4Sharp/Extensions/ResourceMethods.cs b/src/C4Sharp/Extensions/ResourceMethods.cs
index 9b5e836..e48a5a4 100644
--- a/src/C4Sharp/Extensions/ResourceMethods.cs
+++ b/src/C4Sharp/Extensions/ResourceMethods.cs
@@ -2,7 +2,7 @@
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Reflection;
-using C4Sharp.Models.Plantuml;
+using C4Sharp.Models.Plantuml.IO;
 
 namespace C4Sharp.Extensions
 {
@@ -12,24 +12,17 @@ namespace C4Sharp.Extensions
     [ExcludeFromCodeCoverage]
     internal static class ResourceMethods
     {
-        /// <summary>
-        /// Get Stream from plantuml.jar file
-        /// </summary>
-        /// <returns>Stream</returns>
-        /// <exception cref="PlantumlException"></exception>
-        public static Stream GetPlantumlResource() => GetResourceByName("C4Sharp.Resources.plantuml.jar");
-
         /// <summary>
         /// Get resource string content from resource file
         /// </summary>
         /// <param name="name">file name</param>
         /// <returns>resource content</returns>
         /// <exception cref="PlantumlException"></exception>
-        public static string GetResource(string name)
+        public static string GetResourceContent(string name)
         {
             try
             {
-                using var stream = GetResourceByName($"C4Sharp.Resources.{name}");
+                using var stream = GetResourceStream(name);
                 using var reader = new StreamReader(stream ?? throw new InvalidOperationException());
                 return reader.ReadToEnd();
             }
@@ -45,13 +38,13 @@ public static string GetResource(string name)
         /// <param name="name"></param>
         /// <returns></returns>
         /// <exception cref="PlantumlException"></exception>
-        private static Stream GetResourceByName(string name)
+        public static Stream? GetResourceStream(string name)
         {
             try
             {
                 return Assembly
                     .GetExecutingAssembly()
-                    .GetManifestResourceStream(name);
+                    .GetManifestResourceStream($"C4Sharp.Resources.{name}");
             }
             catch (Exception e)
             {
diff --git a/src/C4Sharp/FileSystem/C4SharpDirectory.cs b/src/C4Sharp/FileSystem/C4SharpDirectory.cs
index da62fea..1d523cd 100644
--- a/src/C4Sharp/FileSystem/C4SharpDirectory.cs
+++ b/src/C4Sharp/FileSystem/C4SharpDirectory.cs
@@ -17,48 +17,5 @@ internal static class C4SharpDirectory
         /// Default Resource Folder Name
         /// </summary>
         public static string ResourcesFolderName => Path.Join("..", ".c4s");
-
-        /// <summary>
-        /// Load all C4_Plantuml files
-        /// </summary>
-        public static void LoadResources(string path = null)
-        {
-            var local = path is null
-                ? Path.Join(DirectoryName, ResourcesFolderName)
-                : Path.Join(path, ResourcesFolderName);
-            
-            LoadResource(local, "C4");
-            LoadResource(local, "C4_Component");
-            LoadResource(local, "C4_Container");
-            LoadResource(local, "C4_Context");
-            LoadResource(local, "C4_Deployment");
-        }
-
-        /// <summary>
-        /// Load C4_Plantuml file
-        /// </summary>
-        /// <param name="resourcesPath"></param>
-        /// <param name="resourceName"></param>
-        /// <exception cref="C4FileException"></exception>
-        private static void LoadResource(string resourcesPath, string resourceName)
-        {
-            try
-            {
-                var path = Path.Join(resourcesPath, $"{resourceName}.puml");
-
-                if (File.Exists(path))
-                {
-                    return;
-                }
-
-                var stream = ResourceMethods.GetResource($"{resourceName}.puml");
-                Directory.CreateDirectory(resourcesPath);
-                File.WriteAllText(path, stream);
-            }
-            catch (Exception e)
-            {
-                throw new C4FileException("An exception occured while the package try loading the resource files", e);
-            }
-        }        
     }
 }
\ No newline at end of file
diff --git a/src/C4Sharp/Models/Component.cs b/src/C4Sharp/Models/Component.cs
index 58f2418..dde6119 100644
--- a/src/C4Sharp/Models/Component.cs
+++ b/src/C4Sharp/Models/Component.cs
@@ -15,6 +15,6 @@ namespace C4Sharp.Models
     /// </summary>
     public sealed record Component(string Alias, string Label) : Structure(Alias, Label)
     {
-        public string Technology { get; init; }
+        public string? Technology { get; init; }
     }
 }
\ No newline at end of file
diff --git a/src/C4Sharp/Models/Container.cs b/src/C4Sharp/Models/Container.cs
index ad497ba..b6ddfa8 100644
--- a/src/C4Sharp/Models/Container.cs
+++ b/src/C4Sharp/Models/Container.cs
@@ -19,7 +19,7 @@ public sealed record Container(string Alias, string Label) : Structure(Alias, La
     {
         private readonly Dictionary<int, Container> _instances = new();
         public ContainerType ContainerType{ get; init; }
-        public string Technology { get; init; }
+        public string? Technology { get; init; }
         public Container this[int index] => this.GetInstance(index);
 
         /// <summary>
diff --git a/src/C4Sharp/Models/ContainerBoundary.cs b/src/C4Sharp/Models/ContainerBoundary.cs
index 17d8796..4e81e18 100644
--- a/src/C4Sharp/Models/ContainerBoundary.cs
+++ b/src/C4Sharp/Models/ContainerBoundary.cs
@@ -9,7 +9,7 @@ namespace C4Sharp.Models
     /// </summary>
     public sealed record ContainerBoundary(string Alias, string Label) : Structure(Alias, Label)
     {
-        public IEnumerable<Component> Components { get; init; }
+        public IEnumerable<Component> Components { get; init; } = Array.Empty<Component>();
         public IEnumerable<Relationship> Relationships { get; init; } = Array.Empty<Relationship>();
     }
 }
\ No newline at end of file
diff --git a/src/C4Sharp/Models/DeploymentNode.cs b/src/C4Sharp/Models/DeploymentNode.cs
index 3186296..2911466 100644
--- a/src/C4Sharp/Models/DeploymentNode.cs
+++ b/src/C4Sharp/Models/DeploymentNode.cs
@@ -13,7 +13,7 @@ namespace C4Sharp.Models
     public sealed record DeploymentNode(string Alias, string Label) : Structure(Alias, Label)
     {
         public IEnumerable<DeploymentNode> Nodes { get; init; } = Array.Empty<DeploymentNode>();
-        public Dictionary<string, string> Properties { get; init; }
-        public Container Container { get; init; }
+        public Dictionary<string, string> Properties { get; init; } = new();
+        public Container? Container { get; init; }
     }
 }
\ No newline at end of file
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlDiagram.cs b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlDiagram.cs
similarity index 98%
rename from src/C4Sharp/Models/Plantuml/PlantumlDiagram.cs
rename to src/C4Sharp/Models/Plantuml/Extensions/PlantumlDiagram.cs
index 0548c90..b22bc4f 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlDiagram.cs
+++ b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlDiagram.cs
@@ -3,7 +3,7 @@
 using C4Sharp.Diagrams;
 using C4Sharp.FileSystem;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.Extensions
 {
     /// <summary>
     /// Parser Diagram to PlantUML
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlRelationship.cs b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlRelationship.cs
similarity index 96%
rename from src/C4Sharp/Models/Plantuml/PlantumlRelationship.cs
rename to src/C4Sharp/Models/Plantuml/Extensions/PlantumlRelationship.cs
index e4c77ed..cd69c3d 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlRelationship.cs
+++ b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlRelationship.cs
@@ -1,6 +1,6 @@
 using C4Sharp.Models.Relationships;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.Extensions
 {
     /// <summary>
     /// Parser Relationship to PlantUML
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlStructure.cs b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlStructure.cs
similarity index 97%
rename from src/C4Sharp/Models/Plantuml/PlantumlStructure.cs
rename to src/C4Sharp/Models/Plantuml/Extensions/PlantumlStructure.cs
index 89561f2..517799e 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlStructure.cs
+++ b/src/C4Sharp/Models/Plantuml/Extensions/PlantumlStructure.cs
@@ -3,7 +3,7 @@
 using C4Sharp.Extensions;
 using C4Sharp.Models.Relationships;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.Extensions
 {
     /// <summary>
     /// PlantUML Parser
@@ -134,7 +134,7 @@ private static string ToPumlString(this DeploymentNode deployment, int concat =
                 stream.AppendLine();
             }
 
-            if (deployment.Properties != null)
+            if (deployment.Properties.Any())
             {
                 foreach (var (key, value) in deployment.Properties)
                 {
@@ -142,11 +142,11 @@ private static string ToPumlString(this DeploymentNode deployment, int concat =
                 }
             }
 
-            stream.AppendLine(deployment.Tags is null
+            stream.AppendLine(!deployment.Tags.Any()
                 ? $"{spaces}Deployment_Node({deployment.Alias}, \"{deployment.Label}\", \"{deployment.Description}\") {{"
                 : $"{spaces}Deployment_Node({deployment.Alias}, \"{deployment.Label}\", \"{deployment.Description}\", $tags=\"{string.Join(',', deployment.Tags)}\") {{");
 
-            if (deployment.Nodes != null)
+            if (deployment.Nodes.Any())
             {
                 foreach (var node in deployment.Nodes)
                 {
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlException.cs b/src/C4Sharp/Models/Plantuml/IO/PlantumlException.cs
similarity index 90%
rename from src/C4Sharp/Models/Plantuml/PlantumlException.cs
rename to src/C4Sharp/Models/Plantuml/IO/PlantumlException.cs
index cea6bc5..85e8d1f 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlException.cs
+++ b/src/C4Sharp/Models/Plantuml/IO/PlantumlException.cs
@@ -1,6 +1,6 @@
 using System;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.IO
 {
     /// <summary>
     /// PlantumlException
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlFile.cs b/src/C4Sharp/Models/Plantuml/IO/PlantumlFile.cs
similarity index 95%
rename from src/C4Sharp/Models/Plantuml/PlantumlFile.cs
rename to src/C4Sharp/Models/Plantuml/IO/PlantumlFile.cs
index cbffd6f..07672cd 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlFile.cs
+++ b/src/C4Sharp/Models/Plantuml/IO/PlantumlFile.cs
@@ -1,10 +1,11 @@
-using C4Sharp.Diagrams;
-using C4Sharp.FileSystem;
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
+using C4Sharp.Diagrams;
+using C4Sharp.FileSystem;
+using C4Sharp.Models.Plantuml.Extensions;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.IO
 {
     /// <summary>
     /// PUML File Utils
@@ -55,7 +56,6 @@ public static void Export(this PlantumlSession session, string path, IEnumerable
             {
                 session.Execute(path, true, "svg");
             }
-
         }
 
         /// <summary>
@@ -70,7 +70,6 @@ private static void Save(Diagram diagram, string path, PlantumlSession session)
             {
                 lock (Lock)
                 {
-                    C4SharpDirectory.LoadResources(path);
                     var filePath = Path.Combine(path, $"{diagram.Slug()}.puml");
                     Directory.CreateDirectory(path);
                     File.WriteAllText(filePath, diagram.ToPumlString(session.StandardLibraryBaseUrl));
diff --git a/src/C4Sharp/Models/Plantuml/IO/PlantumlResources.cs b/src/C4Sharp/Models/Plantuml/IO/PlantumlResources.cs
new file mode 100644
index 0000000..6207701
--- /dev/null
+++ b/src/C4Sharp/Models/Plantuml/IO/PlantumlResources.cs
@@ -0,0 +1,77 @@
+using System;
+using System.IO;
+using C4Sharp.Extensions;
+using C4Sharp.FileSystem;
+
+namespace C4Sharp.Models.Plantuml.IO
+{
+    internal static class PlantumlResources
+    {
+        /// <summary>
+        /// Load all C4_Plantuml files
+        /// </summary>
+        public static void LoadResources(string path)
+        {
+            var local = string.IsNullOrEmpty(path)
+                ? Path.Join(C4SharpDirectory.DirectoryName, C4SharpDirectory.ResourcesFolderName)
+                : Path.Join(path, C4SharpDirectory.ResourcesFolderName);
+            
+            LoadResource(local, "C4");
+            LoadResource(local, "C4_Component");
+            LoadResource(local, "C4_Container");
+            LoadResource(local, "C4_Context");
+            LoadResource(local, "C4_Deployment");
+        }
+
+        /// <summary>
+        /// Load C4_Plantuml file
+        /// </summary>
+        /// <param name="resourcesPath"></param>
+        /// <param name="resourceName"></param>
+        /// <exception cref="C4FileException"></exception>
+        private static void LoadResource(string resourcesPath, string resourceName)
+        {
+            try
+            {
+                var path = Path.Join(resourcesPath, $"{resourceName}.puml");
+
+                if (File.Exists(path))
+                {
+                    return;
+                }
+
+                var stream = ResourceMethods.GetResourceContent($"{resourceName}.puml");
+                Directory.CreateDirectory(resourcesPath);
+                File.WriteAllText(path, stream);
+            }
+            catch (Exception e)
+            {
+                throw new C4FileException("An exception occured while the package try loading the resource files", e);
+            }
+        }  
+        
+        /// <summary>
+        /// Get Stream from plantuml.jar file
+        /// </summary>
+        /// <returns>Stream</returns>
+        /// <exception cref="PlantumlException"></exception>
+        public static string LoadPlantumlJar()
+        {
+            try
+            {
+                const string resourceName = "plantuml.jar";
+                var fileName = Path.GetTempFileName();
+
+                var stream = ResourceMethods.GetResourceStream(resourceName) ?? throw new InvalidOperationException();
+                using var file = new FileStream(fileName, FileMode.Create, FileAccess.Write);
+                stream.CopyTo(file);
+
+                return fileName;
+            }
+            catch (Exception e)
+            {
+                throw new PlantumlException($"{nameof(PlantumlException)}: Could not load plantuml engine.", e);
+            }
+        }        
+    }
+}
\ No newline at end of file
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlSession.cs b/src/C4Sharp/Models/Plantuml/IO/PlantumlSession.cs
similarity index 80%
rename from src/C4Sharp/Models/Plantuml/PlantumlSession.cs
rename to src/C4Sharp/Models/Plantuml/IO/PlantumlSession.cs
index 86da69c..6a20dd5 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlSession.cs
+++ b/src/C4Sharp/Models/Plantuml/IO/PlantumlSession.cs
@@ -1,10 +1,9 @@
 using System;
 using System.Diagnostics;
 using System.IO;
-using System.Runtime.Versioning;
 using System.Text;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.IO
 {
     /// <summary>
     /// Session
@@ -14,7 +13,7 @@ public class PlantumlSession : IDisposable
         public bool StandardLibraryBaseUrl { get; private set; }
         public bool GenerateDiagramImages { get; private set; }
         public bool GenerateDiagramSvgImages { get; private set; }
-        private string FilePath { get; }
+        private string? PlantumlJarPath { get; set; }
         private ProcessStartInfo ProcessInfo { get; }
 
         /// <summary>
@@ -22,7 +21,7 @@ public class PlantumlSession : IDisposable
         /// </summary>
         public PlantumlSession()
         {
-            FilePath = PlantumlResource.Load();
+            PlantumlJarPath = null;
             ProcessInfo = new ProcessStartInfo
             {
                 FileName = "java",
@@ -32,23 +31,6 @@ public PlantumlSession()
             };
         }
 
-        /// <summary>
-        /// Constructor with credentials to impersonate
-        /// </summary>
-        /// <param name="username"></param>
-        /// <param name="password"></param>
-        [SupportedOSPlatform("windows")]
-        public PlantumlSession(string username, string password) : this()
-        {
-            if (!OperatingSystem.IsWindows())
-            {
-                return;
-            }
-
-            ProcessInfo.UserName = username;
-            ProcessInfo.PasswordInClearText = password;
-        }
-
         /// <summary>
         /// The C4Sharp has embedded the current version of C4-PluntUML.
         /// But, if you want to use the C4-PlantUML up-to-date version from their repo,
@@ -94,17 +76,20 @@ internal void Execute(string path, bool processWholeDirectory, string generatedI
         {
             try
             {
+                PlantumlResources.LoadResources(path);
+                PlantumlJarPath ??= PlantumlResources.LoadPlantumlJar();
+
                 var directory = processWholeDirectory
                     ? path
-                    : new FileInfo(path)?.Directory?.FullName;                
-                
+                    : new FileInfo(path)?.Directory?.FullName;
+
                 if (string.IsNullOrEmpty(directory))
                 {
                     throw new PlantumlException($"{nameof(PlantumlException)}: puml file not found.");
                 }
 
                 var results = new StringBuilder();
-                
+
                 var jar = CalculateJarCommand(StandardLibraryBaseUrl, generatedImageFormat, directory);
 
                 ProcessInfo.Arguments = $"{jar} {path}";
@@ -129,11 +114,14 @@ private string CalculateJarCommand(bool useStandardLibrary, string generatedImag
             const string includeLocalFilesArg = "-DRELATIVE_INCLUDE=\".\"";
 
             var resourcesOriginArg = useStandardLibrary ? string.Empty : includeLocalFilesArg;
-            var imageFormatOutputArg = string.IsNullOrWhiteSpace(generatedImageFormat) ? string.Empty: $"-t{generatedImageFormat}";
+            var imageFormatOutputArg = string.IsNullOrWhiteSpace(generatedImageFormat)
+                ? string.Empty
+                : $"-t{generatedImageFormat}";
 
-            return $"-jar {FilePath} {resourcesOriginArg} {imageFormatOutputArg} -verbose -o \"{directory}\" -charset UTF-8";
+            return
+                $"-jar {PlantumlJarPath} {resourcesOriginArg} {imageFormatOutputArg} -Playout=smetana -verbose -o \"{directory}\" -charset UTF-8";
         }
-      
+
         /// <summary>
         /// Using the -pipe option, you can easily use PlantUML in your scripts.
         /// With this option, a diagram description is received through standard input and the PNG file is generated to standard output.
@@ -145,13 +133,12 @@ private string CalculateJarCommand(bool useStandardLibrary, string generatedImag
         {
             try
             {
-                var results = new StringBuilder();
-
-                var jar = StandardLibraryBaseUrl
-                    ? $"-jar {FilePath} -verbose -charset UTF-8"
-                    : $"-jar {FilePath} -DRELATIVE_INCLUDE=\".\" -verbose -charset UTF-8";
+                PlantumlJarPath ??= PlantumlResources.LoadPlantumlJar();
 
+                var results = new StringBuilder();
                 var fileName = Guid.NewGuid().ToString("N");
+                var standardLibraryBaseUrlArgs = StandardLibraryBaseUrl ? string.Empty : "-DRELATIVE_INCLUDE=\".\"";
+                var jar = $"-jar {PlantumlJarPath} {standardLibraryBaseUrlArgs} -Playout=smetana -verbose -charset UTF-8";
                 
                 ProcessInfo.Arguments = $"{jar} -pipe > {fileName}.png";
                 ProcessInfo.RedirectStandardOutput = true;
@@ -159,11 +146,8 @@ private string CalculateJarCommand(bool useStandardLibrary, string generatedImag
                 ProcessInfo.StandardOutputEncoding = Encoding.UTF8;
 
                 var process = new Process { StartInfo = ProcessInfo };
-                
-                process.OutputDataReceived += (p, args) =>
-                {
-                    results.AppendLine(args.Data);
-                };
+
+                process.OutputDataReceived += (_, args) => { results.AppendLine(args.Data); };
 
                 process.Start();
                 process.StandardInput.Write(input);
@@ -186,7 +170,17 @@ private string CalculateJarCommand(bool useStandardLibrary, string generatedImag
         /// </summary>
         public void Dispose()
         {
-            PlantumlResource.Clear(FilePath);
+            try
+            {
+                if (PlantumlJarPath is not null)
+                {
+                    File.Delete(PlantumlJarPath);
+                }
+            }
+            catch
+            {
+                // ignored
+            }
         }
     }
 }
\ No newline at end of file
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlStream.cs b/src/C4Sharp/Models/Plantuml/IO/PlantumlStream.cs
similarity index 54%
rename from src/C4Sharp/Models/Plantuml/PlantumlStream.cs
rename to src/C4Sharp/Models/Plantuml/IO/PlantumlStream.cs
index 57ce704..ac59597 100644
--- a/src/C4Sharp/Models/Plantuml/PlantumlStream.cs
+++ b/src/C4Sharp/Models/Plantuml/IO/PlantumlStream.cs
@@ -1,14 +1,14 @@
-using System.Collections.Generic;
 using System.IO;
 using C4Sharp.Diagrams;
+using C4Sharp.Models.Plantuml.Extensions;
 
-namespace C4Sharp.Models.Plantuml
+namespace C4Sharp.Models.Plantuml.IO
 {
     public static class PlantumlStream
     {
-        private static readonly object Lock = new object();
+        private static readonly object Lock = new();
 
-        public static (string, Stream) GetStream(this PlantumlSession session, Diagram diagram)
+        public static (string fileName, Stream fileContent) GetStream(this PlantumlSession session, Diagram diagram)
         {
             lock (Lock)
             {
diff --git a/src/C4Sharp/Models/Plantuml/PlantumlResource.cs b/src/C4Sharp/Models/Plantuml/PlantumlResource.cs
deleted file mode 100644
index 3a285cd..0000000
--- a/src/C4Sharp/Models/Plantuml/PlantumlResource.cs
+++ /dev/null
@@ -1,51 +0,0 @@
-using System;
-using System.IO;
-using C4Sharp.Extensions;
-
-namespace C4Sharp.Models.Plantuml
-{
-    /// <summary>
-    /// PlantUML Resources
-    /// </summary>    
-    internal static class PlantumlResource
-    {
-        /// <summary>
-        /// Load plantuml.jar as tempfile
-        /// </summary>
-        /// <returns>tempfile name</returns>
-        /// <exception cref="PlantumlException"></exception>
-        public static string Load()
-        {
-            try
-            {
-                var fileName = Path.GetTempFileName();
-
-                using var resource = ResourceMethods.GetPlantumlResource();
-                using var file = new FileStream(fileName, FileMode.Create, FileAccess.Write);
-                resource.CopyTo(file);
-
-                return fileName;
-            }
-            catch (Exception e)
-            {
-                throw new PlantumlException($"{nameof(PlantumlException)}: Could not load plantuml engine.", e);
-            }
-        }
-
-        /// <summary>
-        /// Clear
-        /// </summary>
-        /// <param name="file"></param>
-        public static void Clear(string file)
-        {
-            try
-            {
-                File.Delete(file);
-            }
-            catch
-            {
-                // ignored
-            }
-        }
-    }
-}
\ No newline at end of file
diff --git a/src/C4Sharp/Resources/plantuml.jar b/src/C4Sharp/Resources/plantuml.jar
index f23a1ae..65b4894 100644
Binary files a/src/C4Sharp/Resources/plantuml.jar and b/src/C4Sharp/Resources/plantuml.jar differ
diff --git a/tests/C4Sharp.IntegratedTests/ExportingDiagramTests.cs b/tests/C4Sharp.IntegratedTests/ExportingDiagramTests.cs
index 8abc6f3..83b0519 100644
--- a/tests/C4Sharp.IntegratedTests/ExportingDiagramTests.cs
+++ b/tests/C4Sharp.IntegratedTests/ExportingDiagramTests.cs
@@ -2,7 +2,7 @@
 using System.IO;
 using C4Sharp.Diagrams;
 using C4Sharp.IntegratedTests.Stubs.Diagrams;
-using C4Sharp.Models.Plantuml;
+using C4Sharp.Models.Plantuml.IO;
 using Xunit;
 
 namespace C4Sharp.IntegratedTests
diff --git a/tests/C4Sharp.IntegratedTests/GettingStreamDiagramTests.cs b/tests/C4Sharp.IntegratedTests/GettingStreamDiagramTests.cs
index 82f8b91..961f221 100644
--- a/tests/C4Sharp.IntegratedTests/GettingStreamDiagramTests.cs
+++ b/tests/C4Sharp.IntegratedTests/GettingStreamDiagramTests.cs
@@ -1,6 +1,5 @@
-using C4Sharp.Diagrams;
 using C4Sharp.IntegratedTests.Stubs.Diagrams;
-using C4Sharp.Models.Plantuml;
+using C4Sharp.Models.Plantuml.IO;
 using FluentAssertions;
 using Xunit;
 
diff --git a/tests/C4Sharp.UnitTests/C4Sharp.UnitTests.csproj b/tests/C4Sharp.UnitTests/C4Sharp.UnitTests.csproj
index 1f1ede7..e0c3f61 100644
--- a/tests/C4Sharp.UnitTests/C4Sharp.UnitTests.csproj
+++ b/tests/C4Sharp.UnitTests/C4Sharp.UnitTests.csproj
@@ -21,7 +21,7 @@
     </ItemGroup>
 
     <ItemGroup>
-      <ProjectReference Include="..\..\samples\C4Sharp.Sample\C4Sharp.Sample.csproj" />
+      <ProjectReference Include="..\..\src\C4Sharp\C4Sharp.csproj" />
     </ItemGroup>
 
 </Project>
diff --git a/tests/C4Sharp.UnitTests/Diagrams/DiagramTests.cs b/tests/C4Sharp.UnitTests/Diagrams/DiagramTests.cs
index dbeab6b..92228b4 100644
--- a/tests/C4Sharp.UnitTests/Diagrams/DiagramTests.cs
+++ b/tests/C4Sharp.UnitTests/Diagrams/DiagramTests.cs
@@ -1,10 +1,6 @@
-using System;
 using C4Sharp.Diagrams;
 using C4Sharp.Diagrams.Core;
 using C4Sharp.Diagrams.Supplementary;
-using C4Sharp.Models.Plantuml;
-using C4Sharp.Models.Relationships;
-using C4Sharp.Sample.Diagrams;
 using FluentAssertions;
 using Xunit;