diff --git a/Maria.Core/Maria.Core.csproj b/Maria.Core/Maria.Core.csproj
index 422c63c..5b8db07 100644
--- a/Maria.Core/Maria.Core.csproj
+++ b/Maria.Core/Maria.Core.csproj
@@ -3,6 +3,10 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
   </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
+  </ItemGroup>
     <ItemGroup>
         <Reference Include="UnityEditor, Version=0.0.0.0, Culture=neutral, processorArchitecture=MSIL">
             <HintPath>..\Libraries\Unity\UnityEditor.dll</HintPath>
diff --git a/Maria.Tests/CoreTests.cs b/Maria.Tests/CoreTests.cs
new file mode 100644
index 0000000..72f6086
--- /dev/null
+++ b/Maria.Tests/CoreTests.cs
@@ -0,0 +1,19 @@
+using Maria;
+using NUnit.Framework;
+
+namespace Maria.Tests.Core
+{
+    [TestFixture]
+    public class Tests
+    {
+        [TestCase]
+        public void TestClamp()
+        {
+            Assert.That(Algorithms.clamp(2, 0, 1), Is.EqualTo(1));
+            Assert.That(Algorithms.clamp(-2, 0, 1), Is.EqualTo(0));
+            Assert.That(Algorithms.clamp(2, 10, 10), Is.EqualTo(10));
+            Assert.That(Algorithms.clamp(5, -20, -5), Is.EqualTo(-5));
+            Assert.That(Algorithms.clamp(int.MaxValue, int.MinValue, int.MinValue), Is.EqualTo(int.MinValue));
+        }
+    }
+}
\ No newline at end of file
diff --git a/Maria.Tests/Maria.Tests.csproj b/Maria.Tests/Maria.Tests.csproj
new file mode 100644
index 0000000..62f1307
--- /dev/null
+++ b/Maria.Tests/Maria.Tests.csproj
@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="nunit" Version="3.12.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="3.15.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.4.0"/>
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Maria.Core\Maria.Core.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/Maria.sln b/Maria.sln
index 4bbe3b5..6324d53 100644
--- a/Maria.sln
+++ b/Maria.sln
@@ -9,6 +9,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Maria.Editor", "Maria.Edito
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Maria.Platform", "Maria.Platform\Maria.Platform.csproj", "{4952A773-E7D7-45F8-9777-D48BF70E0712}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Maria.Tests", "Maria.Tests\Maria.Tests.csproj", "{8F996FCB-29BB-49BB-A4D6-29BAFCB03750}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -27,6 +29,10 @@ Global
 		{4952A773-E7D7-45F8-9777-D48BF70E0712}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{4952A773-E7D7-45F8-9777-D48BF70E0712}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{4952A773-E7D7-45F8-9777-D48BF70E0712}.Release|Any CPU.Build.0 = Release|Any CPU
+		{8F996FCB-29BB-49BB-A4D6-29BAFCB03750}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{8F996FCB-29BB-49BB-A4D6-29BAFCB03750}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{8F996FCB-29BB-49BB-A4D6-29BAFCB03750}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{8F996FCB-29BB-49BB-A4D6-29BAFCB03750}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/appveyor.yml b/appveyor.yml
index 98eab01..eafc575 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -18,10 +18,17 @@ skip_commits:
 
 before_build:
   - nuget restore
+  - nuget install OpenCover -OutputDirectory packages -Version 4.6.519
+  - choco install codecov
+
 build:
   project: Maria.sln
   verbosity: minimal
 
+test_script:
+  - .\packages\OpenCover.4.6.519\tools\OpenCover.Console.exe -returntargetcode -register:user -target:"dotnet.exe" -targetargs:"test Maria.Tests\bin\Release\netcoreapp3.1\Maria.Tests.dll" -output:"coverage.xml" -filter:"+[Maria*]* -[Maria.Tests*]* "
+  - codecov -f "coverage.xml"
+
 before_package:
 - ps: .\BuildUnityPackages.ps1