diff --git a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageExtensions.cs b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageExtensions.cs
index bfadd9ed80..2bfdf5d211 100644
--- a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageExtensions.cs
+++ b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageExtensions.cs
@@ -1,8 +1,8 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using Microsoft.AspNet.Diagnostics;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Builder
 {
@@ -17,8 +17,13 @@ namespace Microsoft.AspNet.Builder
         /// </summary>
         /// <param name="builder"></param>
         /// <returns></returns>
-        public static IApplicationBuilder UseDeveloperExceptionPage([NotNull] this IApplicationBuilder builder)
+        public static IApplicationBuilder UseDeveloperExceptionPage(this IApplicationBuilder builder)
         {
+            if (builder == null)
+            {
+                throw new ArgumentNullException(nameof(builder));
+            }
+
             return builder.UseDeveloperExceptionPage(new ErrorPageOptions());
         }
 
@@ -29,8 +34,13 @@ namespace Microsoft.AspNet.Builder
         /// <param name="builder"></param>
         /// <param name="options"></param>
         /// <returns></returns>
-        public static IApplicationBuilder UseDeveloperExceptionPage([NotNull] this IApplicationBuilder builder, ErrorPageOptions options)
+        public static IApplicationBuilder UseDeveloperExceptionPage(this IApplicationBuilder builder, ErrorPageOptions options)
         {
+            if (builder == null)
+            {
+                throw new ArgumentNullException(nameof(builder));
+            }
+
             return builder.UseMiddleware<DeveloperExceptionPageMiddleware>(options);
         }
     }
diff --git a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageMiddleware.cs b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageMiddleware.cs
index 6372b1b846..96ecafc022 100644
--- a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageMiddleware.cs
+++ b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageMiddleware.cs
@@ -13,10 +13,8 @@ using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Diagnostics.Views;
 using Microsoft.AspNet.FileProviders;
 using Microsoft.AspNet.Http;
-using Microsoft.AspNet.Http.Features;
 using Microsoft.Dnx.Compilation;
 using Microsoft.Dnx.Runtime;
-using Microsoft.Framework.Internal;
 using Microsoft.Framework.Logging;
 
 namespace Microsoft.AspNet.Diagnostics
@@ -38,11 +36,21 @@ namespace Microsoft.AspNet.Diagnostics
         /// <param name="next"></param>
         /// <param name="options"></param>
         public DeveloperExceptionPageMiddleware(
-            [NotNull] RequestDelegate next,
-            [NotNull] ErrorPageOptions options,
+            RequestDelegate next,
+            ErrorPageOptions options,
             ILoggerFactory loggerFactory,
             IApplicationEnvironment appEnvironment)
         {
+            if (next == null)
+            {
+                throw new ArgumentNullException(nameof(next));
+            }
+
+            if (options == null)
+            {
+                throw new ArgumentNullException(nameof(options));
+            }
+
             _next = next;
             _options = options;
             _logger = loggerFactory.CreateLogger<DeveloperExceptionPageMiddleware>();
diff --git a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageOptions.cs b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageOptions.cs
index 75b7a3951a..59813d9d53 100644
--- a/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageOptions.cs
+++ b/src/Microsoft.AspNet.Diagnostics/DeveloperExceptionPage/DeveloperExceptionPageOptions.cs
@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-
 using Microsoft.AspNet.FileProviders;
 
 namespace Microsoft.AspNet.Diagnostics
diff --git a/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoExtensions.cs b/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoExtensions.cs
index c7fbe5cd77..d7d885ff73 100644
--- a/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoExtensions.cs
+++ b/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoExtensions.cs
@@ -1,10 +1,10 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using Microsoft.AspNet.Diagnostics;
 using Microsoft.AspNet.Http;
 using Microsoft.Dnx.Runtime;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Builder
 {
@@ -21,9 +21,19 @@ namespace Microsoft.AspNet.Builder
         }
 
         public static IApplicationBuilder UseRuntimeInfoPage(
-            [NotNull] this IApplicationBuilder builder,
-            [NotNull] RuntimeInfoPageOptions options)
+            this IApplicationBuilder builder,
+            RuntimeInfoPageOptions options)
         {
+            if (builder == null)
+            {
+                throw new ArgumentNullException(nameof(builder));
+            }
+
+            if (options == null)
+            {
+                throw new ArgumentNullException(nameof(options));
+            }
+
             var libraryManager = builder.ApplicationServices.GetService(typeof(ILibraryManager)) as ILibraryManager;
             var runtimeEnvironment = builder.ApplicationServices.GetService(typeof(IRuntimeEnvironment)) as IRuntimeEnvironment;
             return builder.Use(next => new RuntimeInfoMiddleware(next, options, libraryManager, runtimeEnvironment).Invoke);
diff --git a/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoMiddleware.cs b/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoMiddleware.cs
index 168a943a76..8a748c22f3 100644
--- a/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoMiddleware.cs
+++ b/src/Microsoft.AspNet.Diagnostics/RuntimeInfo/RuntimeInfoMiddleware.cs
@@ -1,12 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Diagnostics.Views;
 using Microsoft.AspNet.Http;
 using Microsoft.Dnx.Runtime;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Diagnostics
 {
@@ -26,11 +26,31 @@ namespace Microsoft.AspNet.Diagnostics
         /// <param name="next"></param>
         /// <param name="options"></param>
         public RuntimeInfoMiddleware(
-            [NotNull] RequestDelegate next,
-            [NotNull] RuntimeInfoPageOptions options,
-            [NotNull] ILibraryManager libraryManager,
-            [NotNull] IRuntimeEnvironment runtimeEnvironment)
+            RequestDelegate next,
+            RuntimeInfoPageOptions options,
+            ILibraryManager libraryManager,
+            IRuntimeEnvironment runtimeEnvironment)
         {
+            if (next == null)
+            {
+                throw new ArgumentNullException(nameof(next));
+            }
+
+            if (options == null)
+            {
+                throw new ArgumentNullException(nameof(options));
+            }
+
+            if (libraryManager == null)
+            {
+                throw new ArgumentNullException(nameof(libraryManager));
+            }
+
+            if (runtimeEnvironment == null)
+            {
+                throw new ArgumentNullException(nameof(runtimeEnvironment));
+            }
+
             _next = next;
             _options = options;
             _libraryManager = libraryManager;
diff --git a/src/Microsoft.AspNet.Diagnostics/StatusCodePage/StatusCodePagesExtensions.cs b/src/Microsoft.AspNet.Diagnostics/StatusCodePage/StatusCodePagesExtensions.cs
index 33ef114a44..fc3a53feef 100644
--- a/src/Microsoft.AspNet.Diagnostics/StatusCodePage/StatusCodePagesExtensions.cs
+++ b/src/Microsoft.AspNet.Diagnostics/StatusCodePage/StatusCodePagesExtensions.cs
@@ -7,7 +7,6 @@ using System.Threading.Tasks;
 using Microsoft.AspNet.Diagnostics;
 using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Http.Features;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Builder
 {
@@ -20,8 +19,13 @@ namespace Microsoft.AspNet.Builder
         /// <param name="app"></param>
         /// <param name="options"></param>
         /// <returns></returns>
-        public static IApplicationBuilder UseStatusCodePages([NotNull]this IApplicationBuilder app, StatusCodePagesOptions options)
+        public static IApplicationBuilder UseStatusCodePages(this IApplicationBuilder app, StatusCodePagesOptions options)
         {
+            if (app == null)
+            {
+                throw new ArgumentNullException(nameof(app));
+            }
+
             return app.UseMiddleware<StatusCodePagesMiddleware>(options);
         }
 
diff --git a/src/Microsoft.AspNet.Diagnostics/Views/BaseView.cs b/src/Microsoft.AspNet.Diagnostics/Views/BaseView.cs
index 1704fe57d6..5973288e1a 100644
--- a/src/Microsoft.AspNet.Diagnostics/Views/BaseView.cs
+++ b/src/Microsoft.AspNet.Diagnostics/Views/BaseView.cs
@@ -9,7 +9,6 @@ using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Http;
-using Microsoft.Framework.Internal;
 using Microsoft.Framework.WebEncoders;
 
 namespace Microsoft.AspNet.Diagnostics.Views
@@ -90,11 +89,26 @@ namespace Microsoft.AspNet.Diagnostics.Views
         /// <param name="trailer">The value and position of the suffix</param>
         /// <param name="values">The <see cref="AttributeValue"/>s to write.</param>
         protected void WriteAttribute(
-            [NotNull] string name,
-            [NotNull] Tuple<string, int> leader,
-            [NotNull] Tuple<string, int> trailer,
+            string name,
+            Tuple<string, int> leader,
+            Tuple<string, int> trailer,
             params AttributeValue[] values)
         {
+            if (name == null)
+            {
+                throw new ArgumentNullException(nameof(name));
+            }
+
+            if (leader == null)
+            {
+                throw new ArgumentNullException(nameof(leader));
+            }
+
+            if (trailer == null)
+            {
+                throw new ArgumentNullException(nameof(trailer));
+            }
+
             WriteAttributeTo(
                 Output,
                 name,
@@ -112,12 +126,32 @@ namespace Microsoft.AspNet.Diagnostics.Views
         /// <param name="trailer">The value and position of the suffix</param>
         /// <param name="values">The <see cref="AttributeValue"/>s to write.</param>
         protected void WriteAttributeTo(
-            [NotNull] TextWriter writer,
-            [NotNull] string name,
-            [NotNull] Tuple<string, int> leader,
-            [NotNull] Tuple<string, int> trailer,
+            TextWriter writer,
+            string name,
+            Tuple<string, int> leader,
+            Tuple<string, int> trailer,
             params AttributeValue[] values)
         {
+            if (writer == null)
+            {
+                throw new ArgumentNullException(nameof(writer));
+            }
+
+            if (name == null)
+            {
+                throw new ArgumentNullException(nameof(name));
+            }
+
+            if (leader == null)
+            {
+                throw new ArgumentNullException(nameof(leader));
+            }
+
+            if (trailer == null)
+            {
+                throw new ArgumentNullException(nameof(trailer));
+            }
+
 
             WriteLiteralTo(writer, leader.Item1);
             foreach (var value in values)
diff --git a/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageExtensions.cs b/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageExtensions.cs
index efb7ff54e5..43eb166ea6 100644
--- a/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageExtensions.cs
+++ b/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageExtensions.cs
@@ -5,7 +5,6 @@
 using System;
 using Microsoft.AspNet.Http;
 using Microsoft.AspNet.Diagnostics;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Builder
 {
@@ -20,8 +19,13 @@ namespace Microsoft.AspNet.Builder
         /// <param name="builder"></param>
         /// <param name="options"></param>
         /// <returns></returns>
-        public static IApplicationBuilder UseWelcomePage([NotNull] this IApplicationBuilder builder, WelcomePageOptions options)
+        public static IApplicationBuilder UseWelcomePage(this IApplicationBuilder builder, WelcomePageOptions options)
         {
+            if (builder == null)
+            {
+                throw new ArgumentNullException(nameof(builder));
+            }
+
             return builder.Use(next => new WelcomePageMiddleware(next, options).Invoke);
         }
 
diff --git a/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageMiddleware.cs b/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageMiddleware.cs
index cb63792d4f..87407f4a52 100644
--- a/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageMiddleware.cs
+++ b/src/Microsoft.AspNet.Diagnostics/WelcomePage/WelcomePageMiddleware.cs
@@ -3,12 +3,10 @@
 
 
 using System;
-using System.Collections.Generic;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Diagnostics.Views;
 using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Http;
-using Microsoft.Framework.Internal;
 
 namespace Microsoft.AspNet.Diagnostics
 {
@@ -25,8 +23,18 @@ namespace Microsoft.AspNet.Diagnostics
         /// </summary>
         /// <param name="next"></param>
         /// <param name="options"></param>
-        public WelcomePageMiddleware([NotNull] RequestDelegate next, [NotNull] WelcomePageOptions options)
+        public WelcomePageMiddleware(RequestDelegate next, WelcomePageOptions options)
         {
+            if (next == null)
+            {
+                throw new ArgumentNullException(nameof(next));
+            }
+
+            if (options == null)
+            {
+                throw new ArgumentNullException(nameof(options));
+            }
+
             _next = next;
             _options = options;
         }
diff --git a/src/Microsoft.AspNet.Diagnostics/project.json b/src/Microsoft.AspNet.Diagnostics/project.json
index b1876933e8..e62e834150 100644
--- a/src/Microsoft.AspNet.Diagnostics/project.json
+++ b/src/Microsoft.AspNet.Diagnostics/project.json
@@ -11,10 +11,6 @@
         "Microsoft.AspNet.Http.Extensions": "1.0.0-*",
         "Microsoft.AspNet.WebUtilities": "1.0.0-*",
         "Microsoft.Framework.Logging.Abstractions": "1.0.0-*",
-        "Microsoft.Framework.NotNullAttribute.Sources": {
-            "type": "build",
-            "version": "1.0.0-*"
-        },
         "Microsoft.Framework.OptionsModel": "1.0.0-*",
         "Microsoft.Dnx.Compilation.Abstractions": "1.0.0-*",
         "Microsoft.Framework.WebEncoders.Core": "1.0.0-*"