diff --git a/src/Microsoft.AspNet.HttpOverrides/OverrideHeaderMiddleware.cs b/src/Microsoft.AspNet.HttpOverrides/OverrideHeaderMiddleware.cs
index b036b9e..dd3cb92 100644
--- a/src/Microsoft.AspNet.HttpOverrides/OverrideHeaderMiddleware.cs
+++ b/src/Microsoft.AspNet.HttpOverrides/OverrideHeaderMiddleware.cs
@@ -6,7 +6,6 @@ using System.Net;
 using System.Threading.Tasks;
 using Microsoft.AspNet.Builder;
 using Microsoft.AspNet.Http;
-using Microsoft.Extensions.Internal;
 
 namespace Microsoft.AspNet.HttpOverrides
 {
@@ -21,8 +20,18 @@ namespace Microsoft.AspNet.HttpOverrides
         private readonly OverrideHeaderMiddlewareOptions _options;
         private readonly RequestDelegate _next;
 
-        public OverrideHeaderMiddleware([NotNull] RequestDelegate next, [NotNull] OverrideHeaderMiddlewareOptions options)
+        public OverrideHeaderMiddleware(RequestDelegate next, OverrideHeaderMiddlewareOptions options)
         {
+            if (next == null)
+            {
+                throw new ArgumentNullException(nameof(next));
+            }
+
+            if (options == null)
+            {
+                throw new ArgumentNullException(nameof(options));
+            }
+
             _options = options;
             _next = next;
         }
diff --git a/src/Microsoft.AspNet.HttpOverrides/project.json b/src/Microsoft.AspNet.HttpOverrides/project.json
index 46de367..d791008 100644
--- a/src/Microsoft.AspNet.HttpOverrides/project.json
+++ b/src/Microsoft.AspNet.HttpOverrides/project.json
@@ -6,8 +6,7 @@
     "url": "git://github.com/aspnet/basicmiddleware"
   },
   "dependencies": {
-    "Microsoft.AspNet.Http.Extensions": "1.0.0-*",
-    "Microsoft.Extensions.NotNullAttribute.Sources": { "version": "1.0.0-*", "type": "build" }
+    "Microsoft.AspNet.Http.Extensions": "1.0.0-*"
   },
   "frameworks": {
     "dnx451": { },