diff --git a/.idea/.idea.ln.collections/.idea/indexLayout.xml b/.idea/.idea.ln.collections/.idea/indexLayout.xml
new file mode 100644
index 0000000..7b08163
--- /dev/null
+++ b/.idea/.idea.ln.collections/.idea/indexLayout.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="UserContentModel">
+    <attachedFolders />
+    <explicitIncludes />
+    <explicitExcludes />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/.idea.ln.collections/.idea/vcs.xml b/.idea/.idea.ln.collections/.idea/vcs.xml
new file mode 100644
index 0000000..94a25f7
--- /dev/null
+++ b/.idea/.idea.ln.collections/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/ln.collections.sln b/ln.collections.sln
new file mode 100644
index 0000000..75e8eb4
--- /dev/null
+++ b/ln.collections.sln
@@ -0,0 +1,48 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 15
+VisualStudioVersion = 15.0.26124.0
+MinimumVisualStudioVersion = 15.0.26124.0
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ln.collections", "ln.collections\ln.collections.csproj", "{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ln.collections.test", "ln.collections.test\ln.collections.test.csproj", "{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Debug|x64 = Debug|x64
+		Debug|x86 = Debug|x86
+		Release|Any CPU = Release|Any CPU
+		Release|x64 = Release|x64
+		Release|x86 = Release|x86
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|x64.Build.0 = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Debug|x86.Build.0 = Debug|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|Any CPU.Build.0 = Release|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|x64.ActiveCfg = Release|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|x64.Build.0 = Release|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|x86.ActiveCfg = Release|Any CPU
+		{8033F5A3-945A-4FA0-8A94-FF9A455BEF29}.Release|x86.Build.0 = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|x64.Build.0 = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Debug|x86.Build.0 = Debug|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|x64.ActiveCfg = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|x64.Build.0 = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|x86.ActiveCfg = Release|Any CPU
+		{C814B1BC-8EAF-4819-BF70-AAAC08235B5C}.Release|x86.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal
diff --git a/ln.collections.test/BTreeTests.cs b/ln.collections.test/BTreeTests.cs
new file mode 100644
index 0000000..ec70516
--- /dev/null
+++ b/ln.collections.test/BTreeTests.cs
@@ -0,0 +1,72 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using NUnit.Framework;
+
+namespace ln.collections.test
+{
+    public class BenchmarkBTree
+    {
+
+        int[] inputs = new int[100000];
+
+        [SetUp]
+        public void Setup()
+        {
+            Random random = new Random();
+            HashSet<int> inputs = new HashSet<int>();
+
+            while (inputs.Count < this.inputs.Length)
+                inputs.Add(random.Next());
+            this.inputs = inputs.ToArray();
+        }
+
+
+        [Test]
+        public void Benchmark()
+        {
+            int iters = 10;
+            
+            BTree<int> btree = new BTree<int>();
+            Meassure(String.Format("BTree({0})", inputs.Length), iters, ()=>{
+                foreach (int n in inputs)
+                    btree.Add(n);
+                
+                btree.Clear();
+            });
+
+            HashSet<int> hashSet = new HashSet<int>(1000000);
+            Meassure(String.Format("HashSet({0})", inputs.Length), iters, ()=>{
+                foreach (int n in inputs)
+                    hashSet.Add(n);
+
+                hashSet.Clear();
+            });
+
+            Dictionary<int, int> dict = new Dictionary<int, int>();
+            Meassure(String.Format("Dictionary({0})", inputs.Length), iters, ()=>{
+                foreach (int n in inputs)
+                    dict.Add(n, n);
+
+                dict.Clear();
+            });
+        }
+
+        public void Meassure(string name, int iterations, Action action)
+        {
+            TestContext.Error.WriteLine("------ NEASSURE -------------------");
+
+            while (iterations-->0)
+            {
+                DateTime start = DateTime.Now;
+                action();
+                DateTime stop = DateTime.Now;
+                TestContext.Error.WriteLine("Meassure: {0}: {1}ms", name, (stop - start).TotalMilliseconds);
+            }
+        }
+        
+
+
+    }
+}
\ No newline at end of file
diff --git a/ln.collections.test/ln.collections.test.csproj b/ln.collections.test/ln.collections.test.csproj
new file mode 100644
index 0000000..c64a042
--- /dev/null
+++ b/ln.collections.test/ln.collections.test.csproj
@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+
+    <IsPackable>false</IsPackable>
+
+    <TargetFrameworks>net5.0;netcoreapp3.1</TargetFrameworks>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="3.16.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />
+    <ProjectReference Include="../ln.collections/ln.collections.csproj" />
+  </ItemGroup>
+
+</Project>