diff --git a/src/SharedInfrastructure/DebugGuard.cs b/src/SharedInfrastructure/DebugGuard.cs
index e79cf8f..34b11c8 100644
--- a/src/SharedInfrastructure/DebugGuard.cs
+++ b/src/SharedInfrastructure/DebugGuard.cs
@@ -2,6 +2,7 @@
 // Licensed under the Six Labors Split License.
 
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Runtime.CompilerServices;
 
 namespace SixLabors;
@@ -22,33 +23,25 @@ internal static partial class DebugGuard
     /// <typeparam name="TValue">The type of the value.</typeparam>
     /// <exception cref="ArgumentNullException"><paramref name="value"/> is null.</exception>
     [Conditional("DEBUG")]
-    public static void NotNull<TValue>(TValue value, string parameterName)
-        where TValue : class
-    {
-        if (value is null)
-        {
-            ThrowArgumentNullException(parameterName);
-        }
-    }
+    public static void NotNull<TValue>([NotNull] TValue? value, [CallerArgumentExpression("value")] string? parameterName = null)
+        where TValue : class =>
+        ArgumentNullException.ThrowIfNull(value, parameterName);
 
     /// <summary>
     /// Ensures that the target value is not null, empty, or whitespace.
     /// </summary>
     /// <param name="value">The target string, which should be checked against being null or empty.</param>
-    /// <param name="parameterName">Name of the parameter.</param>
+    /// <param name="paramName">Name of the parameter.</param>
     /// <exception cref="ArgumentNullException"><paramref name="value"/> is null.</exception>
     /// <exception cref="ArgumentException"><paramref name="value"/> is empty or contains only blanks.</exception>
     [Conditional("DEBUG")]
-    public static void NotNullOrWhiteSpace(string value, string parameterName)
+    public static void NotNullOrWhiteSpace([NotNull] string? value, [CallerArgumentExpression("value")] string? paramName = null)
     {
-        if (value is null)
-        {
-            ThrowArgumentNullException(parameterName);
-        }
+        ArgumentNullException.ThrowIfNull(value);
 
         if (string.IsNullOrWhiteSpace(value))
         {
-            ThrowArgumentException("Must not be empty or whitespace.", parameterName);
+            ThrowArgumentException("Must not be empty or whitespace.", paramName!);
         }
     }
 
@@ -155,7 +148,9 @@ public static void MustBeBetweenOrEqualTo<TValue>(TValue value, TValue min, TVal
     {
         if (value.CompareTo(min) < 0 || value.CompareTo(max) > 0)
         {
-            ThrowArgumentOutOfRangeException(parameterName, $"Value {value} must be greater than or equal to {min} and less than or equal to {max}.");
+            ThrowArgumentOutOfRangeException(
+                parameterName,
+                $"Value {value} must be greater than or equal to {min} and less than or equal to {max}.");
         }
     }
 
@@ -282,8 +277,4 @@ private static void ThrowArgumentException(string message, string parameterName)
     [MethodImpl(MethodImplOptions.NoInlining)]
     private static void ThrowArgumentOutOfRangeException(string parameterName, string message) =>
         throw new ArgumentOutOfRangeException(parameterName, message);
-
-    [MethodImpl(MethodImplOptions.NoInlining)]
-    private static void ThrowArgumentNullException(string parameterName) =>
-        throw new ArgumentNullException(parameterName);
 }
diff --git a/src/SharedInfrastructure/Guard.cs b/src/SharedInfrastructure/Guard.cs
index 8fa2c9a..7dd3569 100644
--- a/src/SharedInfrastructure/Guard.cs
+++ b/src/SharedInfrastructure/Guard.cs
@@ -2,6 +2,7 @@
 // Licensed under the Six Labors Split License.
 
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Runtime.CompilerServices;
 
 namespace SixLabors;
@@ -20,16 +21,9 @@ internal static partial class Guard
     /// <typeparam name="TValue">The type of the value.</typeparam>
     /// <exception cref="ArgumentNullException"><paramref name="value"/> is null.</exception>
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public static void NotNull<TValue>(TValue value, string parameterName)
-        where TValue : class
-    {
-        if (value is not null)
-        {
-            return;
-        }
-
-        ThrowHelper.ThrowArgumentNullExceptionForNotNull(parameterName);
-    }
+    public static void NotNull<TValue>([NotNull]TValue? value, [CallerArgumentExpression("value")] string? parameterName = null)
+        where TValue : class =>
+        ArgumentNullException.ThrowIfNull(value, parameterName);
 
     /// <summary>
     /// Ensures that the target value is not null, empty, or whitespace.
diff --git a/src/SharedInfrastructure/ThrowHelper.cs b/src/SharedInfrastructure/ThrowHelper.cs
index 3516df2..29afa66 100644
--- a/src/SharedInfrastructure/ThrowHelper.cs
+++ b/src/SharedInfrastructure/ThrowHelper.cs
@@ -13,21 +13,13 @@ namespace SixLabors;
 internal static partial class ThrowHelper
 #pragma warning restore RCS1043 // Remove 'partial' modifier from type with a single part.
 {
-    /// <summary>
-    /// Throws an <see cref="ArgumentNullException"/> when <see cref="Guard.NotNull{TValue}"/> fails.
-    /// </summary>
-    /// <param name="name">The argument name.</param>
-    [DoesNotReturn]
-    public static void ThrowArgumentNullExceptionForNotNull(string name)
-        => ThrowArgumentNullException(name, $"Parameter \"{name}\" must be not null.");
-
     /// <summary>
     /// Throws an <see cref="ArgumentException"/> when <see cref="Guard.NotNullOrWhiteSpace"/> fails.
     /// </summary>
     /// <param name="value">The value.</param>
     /// <param name="name">The argument name.</param>
     [DoesNotReturn]
-    public static void ThrowArgumentExceptionForNotNullOrWhitespace(string value, string name)
+    public static void ThrowArgumentExceptionForNotNullOrWhitespace(string? value, string name)
     {
         if (value is null)
         {
diff --git a/tests/SharedInfrastructure.Tests/SharedInfrastructure.Tests.csproj b/tests/SharedInfrastructure.Tests/SharedInfrastructure.Tests.csproj
index 2878748..65dfed4 100644
--- a/tests/SharedInfrastructure.Tests/SharedInfrastructure.Tests.csproj
+++ b/tests/SharedInfrastructure.Tests/SharedInfrastructure.Tests.csproj
@@ -4,6 +4,7 @@
     <TargetFrameworks>net6.0;</TargetFrameworks>
     <AssemblyName>SharedInfrastructure.Tests</AssemblyName>
     <RootNamespace>SharedInfrastructure.Tests</RootNamespace>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>