diff --git a/DistIL.sln b/DistIL.sln
index 86cb745..5244d34 100644
--- a/DistIL.sln
+++ b/DistIL.sln
@@ -17,6 +17,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "PracticeTests", "tests\Prac
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Benchmarks", "tests\Benchmarks\Benchmarks.csproj", "{3CE5B206-AEC2-4A18-9ECF-8DAF17CB893F}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DistIL.Testing", "src\DistIL.Testing\DistIL.Testing.csproj", "{D3E25BCB-E6EC-436A-8BA1-269BFB248764}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -47,6 +49,10 @@ Global
 		{3CE5B206-AEC2-4A18-9ECF-8DAF17CB893F}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{3CE5B206-AEC2-4A18-9ECF-8DAF17CB893F}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{3CE5B206-AEC2-4A18-9ECF-8DAF17CB893F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{D3E25BCB-E6EC-436A-8BA1-269BFB248764}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D3E25BCB-E6EC-436A-8BA1-269BFB248764}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D3E25BCB-E6EC-436A-8BA1-269BFB248764}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D3E25BCB-E6EC-436A-8BA1-269BFB248764}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/src/DistIL.Testing/DistIL.Testing.csproj b/src/DistIL.Testing/DistIL.Testing.csproj
new file mode 100644
index 0000000..6a94274
--- /dev/null
+++ b/src/DistIL.Testing/DistIL.Testing.csproj
@@ -0,0 +1,28 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <IsPackable>true</IsPackable>
+    <PackageId>DistIL.Testing</PackageId>
+    <Description>Testing suite for DistIL</Description>
+
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <!-- Don't warn about missing xmldocs for public entities. -->
+    <NoWarn>CS1591;CS1573</NoWarn>
+
+    <IncludeSymbols>true</IncludeSymbols>
+    <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <EmbedUntrackedSources>true</EmbedUntrackedSources>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="All" />
+    <PackageReference Include="Shouldly" Version="4.3.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\DistIL\DistIL.csproj" />
+  </ItemGroup>
+
+</Project>
diff --git a/src/DistIL.Testing/ModuleAssertions.cs b/src/DistIL.Testing/ModuleAssertions.cs
new file mode 100644
index 0000000..1fe4391
--- /dev/null
+++ b/src/DistIL.Testing/ModuleAssertions.cs
@@ -0,0 +1,46 @@
+using DistIL.AsmIO;
+
+using Shouldly;
+
+namespace DistIL.Testing;
+
+[ShouldlyMethods]
+public static class ModuleAssertions
+{
+    public static void ShouldHaveName(this ModuleDef module, string name)
+    {
+        module.AsmName.Name.ShouldBe(name);
+    }
+
+    public static void ShouldHaveVersion(this ModuleDef module, Version version)
+    {
+        module.AsmName.Version.ShouldBe(version);
+    }
+
+    public static void ShouldHaveCustomAttribute(this ModuleDef module, string fullname, bool forAssembly = true)
+    {
+        module.GetCustomAttribs(forAssembly).Any(ca => $"{ca.Type.Namespace}.{ca.Type.Name}" == fullname).ShouldBeTrue();
+    }
+
+    public static void ShouldHaveCustomAttribute<TAttribute>(this ModuleDef module, bool forAssembly = true)
+        where TAttribute : Attribute
+    {
+        module.ShouldHaveCustomAttribute(typeof(TAttribute)!.FullName!, forAssembly);
+    }
+
+    public static void ShouldContainType(this ModuleDef module, string ns, string name, bool includeExports = true)
+    {
+        module.FindType(ns, name, includeExports, throwIfNotFound: true).ShouldNotBeNull();
+    }
+
+    public static void ShouldNotContainType(this ModuleDef module, string ns, string name, bool includeExports = true)
+    {
+        module.FindType(ns, name, includeExports, throwIfNotFound: false).ShouldBeNull();
+    }
+
+    public static void ShouldTargetRuntimeVersion(this ModuleDef module, string version)
+    {
+        module.GetCustomAttribs(true).FirstOrDefault(a => a.Type.Namespace == "System.Runtime.Versioning" && a.Type.Name == "TargetFrameworkAttribute")?
+            .Args[0].ShouldBe(".NETCoreApp,Version=v" + version);
+    }
+}
diff --git a/src/DistIL.Testing/ModuleEntityAssertions.cs b/src/DistIL.Testing/ModuleEntityAssertions.cs
new file mode 100644
index 0000000..6c80a40
--- /dev/null
+++ b/src/DistIL.Testing/ModuleEntityAssertions.cs
@@ -0,0 +1,20 @@
+using DistIL.AsmIO;
+
+using Shouldly;
+
+namespace DistIL.Testing;
+
+[ShouldlyMethods]
+public static class ModuleEntityAssertions
+{
+    public static void ShouldHaveCustomAttribute(this ModuleEntity entity, string fullname)
+    {
+        entity.GetCustomAttribs(true).Any(ca => $"{ca.Type.Namespace}.{ca.Type.Name}" == fullname).ShouldBeTrue();
+    }
+
+    public static void ShouldHaveCustomAttribute<TAttribute>(this ModuleEntity entity)
+        where TAttribute : Attribute
+    {
+        entity.ShouldHaveCustomAttribute(typeof(TAttribute)!.FullName!);
+    }
+}
\ No newline at end of file
diff --git a/src/DistIL.Testing/TypeAssertions.cs b/src/DistIL.Testing/TypeAssertions.cs
new file mode 100644
index 0000000..f3d5e0b
--- /dev/null
+++ b/src/DistIL.Testing/TypeAssertions.cs
@@ -0,0 +1,120 @@
+using System.Reflection;
+using System.Runtime.CompilerServices;
+
+using DistIL.AsmIO;
+
+using Shouldly;
+
+namespace DistIL.Testing;
+
+[ShouldlyMethods]
+public static class TypeAssertions
+{
+    public static void ShouldHaveName(this TypeDef type, string name)
+    {
+        type.Name.ShouldBe(name);
+    }
+
+    public static void ShouldHaveNamespace(this TypeDef type, string ns)
+    {
+        type.Namespace.ShouldBe(ns);
+    }
+
+    public static void ShouldHaveBaseType(this TypeDef type, string ns, string name)
+    {
+        type.BaseType.ShouldNotBeNull();
+        type.BaseType!.Namespace.ShouldBe(ns);
+        type.BaseType!.Name.ShouldBe(name);
+    }
+
+    public static void ShouldBeEnum(this TypeDef type)
+    {
+        type.IsEnum.ShouldBeTrue();
+    }
+
+    public static void ShouldBeEnumWithFlags(this TypeDef type)
+    {
+        type.IsEnum.ShouldBeTrue();
+        type.HasCustomAttrib(typeof(FlagsAttribute));
+    }
+
+    public static void ShouldBeClass(this TypeDef type)
+    {
+        type.IsClass.ShouldBeTrue();
+    }
+
+    public static void ShouldBeInterface(this TypeDef type)
+    {
+        type.IsInterface.ShouldBeTrue();
+    }
+
+    public static void ShouldBeValueType(this TypeDef type)
+    {
+        type.IsValueType.ShouldBeTrue();
+    }
+
+    public static void ShouldBeAbstract(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.Abstract).ShouldBeTrue();
+    }
+
+    public static void ShouldBeSealed(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.Sealed).ShouldBeTrue();
+    }
+
+    public static void ShouldBePublic(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.Public).ShouldBeTrue();
+    }
+
+    public static void ShouldBePrivate(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.NotPublic).ShouldBeTrue();
+    }
+
+    public static void ShouldBeInternal(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.NestedAssembly).ShouldBeTrue();
+    }
+
+    public static void ShouldBeProtected(this TypeDef type)
+    {
+        type.Attribs.HasFlag(TypeAttributes.NestedFamily).ShouldBeTrue();
+    }
+
+    public static void ShouldImplement(this TypeDef type, string ns, string name)
+    {
+        type.Interfaces.ShouldContain(i => i.Namespace == ns && i.Name == name);
+    }
+
+    public static void ShouldImplement<T>(this TypeDef type)
+    {
+        type.Interfaces.ShouldContain(i => i.Namespace == typeof(T).Namespace && i.Name == typeof(T).Name);
+    }
+
+    public static void ShouldHaveField(this TypeDef type, string name, string fieldType)
+    {
+        type.Fields.ShouldContain(f => f.Name == name && f.Type.Namespace == fieldType);
+    }
+
+    public static void ShouldHaveProperty(this TypeDef type, string name)
+    {
+        type.Properties.ShouldContain(p => p.Name == name);
+    }
+
+    public static void ShouldHaveMethod(this TypeDef type, string name)
+    {
+        type.Methods.ShouldContain(m => m.Name == name);
+    }
+
+    public static void ShouldHaveMethod(this TypeDef type, string name, string returnType)
+    {
+        type.Methods.ShouldContain(m => m.Name == name && m.ReturnType.Namespace == returnType);
+    }
+
+    public static void ShouldHaveEvent(this TypeDef type, string name)
+    {
+        type.Events.ShouldContain(e => e.Name == name);
+    }
+}