diff --git a/src/Microsoft.AspNetCore.Hosting.Abstractions/HostingAbstractionsWebHostBuilderExtensions.cs b/src/Microsoft.AspNetCore.Hosting.Abstractions/HostingAbstractionsWebHostBuilderExtensions.cs
new file mode 100644
index 0000000000..7e62cbeac0
--- /dev/null
+++ b/src/Microsoft.AspNetCore.Hosting.Abstractions/HostingAbstractionsWebHostBuilderExtensions.cs
@@ -0,0 +1,177 @@
+// 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.Linq;
+using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Microsoft.AspNetCore.Hosting
+{
+    public static class HostingAbstractionsWebHostBuilderExtensions
+    {
+        private static readonly string ServerUrlsSeparator = ";";
+
+        /// <summary>
+        /// Use the given configuration settings on the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="configuration">The <see cref="IConfiguration"/> containing settings to be used.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseConfiguration(this IWebHostBuilder hostBuilder, IConfiguration configuration)
+        {
+            foreach (var setting in configuration.AsEnumerable())
+            {
+                hostBuilder.UseSetting(setting.Key, setting.Value);
+            }
+
+            return hostBuilder;
+        }
+
+        /// <summary>
+        /// Set whether startup errors should be captured in the configuration settings of the web host.
+        /// When enabled, startup exceptions will be caught and an error page will be returned. If disabled, startup exceptions will be propagated.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="captureStartupErrors"><c>true</c> to use startup error page; otherwise <c>false</c>.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder CaptureStartupErrors(this IWebHostBuilder hostBuilder, bool captureStartupErrors)
+        {
+            return hostBuilder.UseSetting(WebHostDefaults.CaptureStartupErrorsKey, captureStartupErrors ? "true" : "false");
+        }
+
+        /// <summary>
+        /// Specify the assembly containing the startup type to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="startupAssemblyName">The name of the assembly containing the startup type.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseStartup(this IWebHostBuilder hostBuilder, string startupAssemblyName)
+        {
+            if (startupAssemblyName == null)
+            {
+                throw new ArgumentNullException(nameof(startupAssemblyName));
+            }
+
+
+            return hostBuilder
+                    .UseSetting(WebHostDefaults.ApplicationKey, startupAssemblyName)
+                    .UseSetting(WebHostDefaults.StartupAssemblyKey, startupAssemblyName);
+        }
+
+        /// <summary>
+        /// Specify the assembly containing the server to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="assemblyName">The name of the assembly containing the server to be used.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseServer(this IWebHostBuilder hostBuilder, string assemblyName)
+        {
+            if (assemblyName == null)
+            {
+                throw new ArgumentNullException(nameof(assemblyName));
+            }
+
+            return hostBuilder.UseSetting(WebHostDefaults.ServerKey, assemblyName);
+        }
+
+        /// <summary>
+        /// Specify the server to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="server">The <see cref="IServer"/> to be used.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseServer(this IWebHostBuilder hostBuilder, IServer server)
+        {
+            if (server == null)
+            {
+                throw new ArgumentNullException(nameof(server));
+            }
+
+            return hostBuilder.ConfigureServices(services =>
+            {
+                // It would be nicer if this was transient but we need to pass in the
+                // factory instance directly
+                services.AddSingleton(server);
+            });
+        }
+
+        /// <summary>
+        /// Specify the environment to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="environment">The environment to host the application in.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseEnvironment(this IWebHostBuilder hostBuilder, string environment)
+        {
+            if (environment == null)
+            {
+                throw new ArgumentNullException(nameof(environment));
+            }
+
+            return hostBuilder.UseSetting(WebHostDefaults.EnvironmentKey, environment);
+        }
+
+        /// <summary>
+        /// Specify the content root directory to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="contentRoot">Path to root directory of the application.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseContentRoot(this IWebHostBuilder hostBuilder, string contentRoot)
+        {
+            if (contentRoot == null)
+            {
+                throw new ArgumentNullException(nameof(contentRoot));
+            }
+
+            return hostBuilder.UseSetting(WebHostDefaults.ContentRootKey, contentRoot);
+        }
+
+        /// <summary>
+        /// Specify the webroot directory to be used by the web host.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="webRoot">Path to the root directory used by the web server.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseWebRoot(this IWebHostBuilder hostBuilder, string webRoot)
+        {
+            if (webRoot == null)
+            {
+                throw new ArgumentNullException(nameof(webRoot));
+            }
+
+            return hostBuilder.UseSetting(WebHostDefaults.WebRootKey, webRoot);
+        }
+
+        /// <summary>
+        /// Specify the urls the web host will listen on.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
+        /// <param name="urls">The urls the hosted application will listen on.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHostBuilder UseUrls(this IWebHostBuilder hostBuilder, params string[] urls)
+        {
+            if (urls == null)
+            {
+                throw new ArgumentNullException(nameof(urls));
+            }
+
+            return hostBuilder.UseSetting(WebHostDefaults.ServerUrlsKey, string.Join(ServerUrlsSeparator, urls));
+        }
+
+        /// <summary>
+        /// Start the web host and listen on the speficied urls.
+        /// </summary>
+        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to start.</param>
+        /// <param name="urls">The urls the hosted application will listen on.</param>
+        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
+        public static IWebHost Start(this IWebHostBuilder hostBuilder, params string[] urls)
+        {
+            var host = hostBuilder.UseUrls(urls).Build();
+            host.Start();
+            return host;
+        }
+    }
+}
diff --git a/src/Microsoft.AspNetCore.Hosting/WebHostBuilderExtensions.cs b/src/Microsoft.AspNetCore.Hosting/WebHostBuilderExtensions.cs
index 7d64c8aaca..7b33bebe4c 100644
--- a/src/Microsoft.AspNetCore.Hosting/WebHostBuilderExtensions.cs
+++ b/src/Microsoft.AspNetCore.Hosting/WebHostBuilderExtensions.cs
@@ -2,48 +2,15 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Linq;
 using System.Reflection;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting.Internal;
-using Microsoft.AspNetCore.Hosting.Server;
-using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace Microsoft.AspNetCore.Hosting
 {
     public static class WebHostBuilderExtensions
     {
-        private static readonly string ServerUrlsSeparator = ";";
-
-        /// <summary>
-        /// Use the given configuration settings on the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="configuration">The <see cref="IConfiguration"/> containing settings to be used.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseConfiguration(this IWebHostBuilder hostBuilder, IConfiguration configuration)
-        {
-            foreach (var setting in configuration.AsEnumerable())
-            {
-                hostBuilder.UseSetting(setting.Key, setting.Value);
-            }
-
-            return hostBuilder;
-        }
-
-        /// <summary>
-        /// Set whether startup errors should be captured in the configuration settings of the web host.
-        /// When enabled, startup exceptions will be caught and an error page will be returned. If disabled, startup exceptions will be propagated.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="captureStartupErrors"><c>true</c> to use startup error page; otherwise <c>false</c>.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder CaptureStartupErrors(this IWebHostBuilder hostBuilder, bool captureStartupErrors)
-        {
-            return hostBuilder.UseSetting(WebHostDefaults.CaptureStartupErrorsKey, captureStartupErrors ? "true" : "false");
-        }
-
         /// <summary>
         /// Specify the startup method to be used to configure the web application.
         /// </summary>
@@ -105,122 +72,5 @@ namespace Microsoft.AspNetCore.Hosting
         {
             return hostBuilder.UseStartup(typeof(TStartup));
         }
-
-        /// <summary>
-        /// Specify the assembly containing the startup type to be used by the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="startupAssemblyName">The name of the assembly containing the startup type.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseStartup(this IWebHostBuilder hostBuilder, string startupAssemblyName)
-        {
-            if (startupAssemblyName == null)
-            {
-                throw new ArgumentNullException(nameof(startupAssemblyName));
-            }
-
-
-            return hostBuilder
-                    .UseSetting(WebHostDefaults.ApplicationKey, startupAssemblyName)
-                    .UseSetting(WebHostDefaults.StartupAssemblyKey, startupAssemblyName);
-        }
-
-        /// <summary>
-        /// Specify the server to be used by the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="server">The <see cref="IServer"/> to be used.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseServer(this IWebHostBuilder hostBuilder, IServer server)
-        {
-            if (server == null)
-            {
-                throw new ArgumentNullException(nameof(server));
-            }
-
-            return hostBuilder.ConfigureServices(services =>
-            {
-                // It would be nicer if this was transient but we need to pass in the
-                // factory instance directly
-                services.AddSingleton(server);
-            });
-        }
-
-        /// <summary>
-        /// Specify the environment to be used by the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="environment">The environment to host the application in.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseEnvironment(this IWebHostBuilder hostBuilder, string environment)
-        {
-            if (environment == null)
-            {
-                throw new ArgumentNullException(nameof(environment));
-            }
-
-            return hostBuilder.UseSetting(WebHostDefaults.EnvironmentKey, environment);
-        }
-
-        /// <summary>
-        /// Specify the content root directory to be used by the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="contentRoot">Path to root directory of the application.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseContentRoot(this IWebHostBuilder hostBuilder, string contentRoot)
-        {
-            if (contentRoot == null)
-            {
-                throw new ArgumentNullException(nameof(contentRoot));
-            }
-
-            return hostBuilder.UseSetting(WebHostDefaults.ContentRootKey, contentRoot);
-        }
-
-        /// <summary>
-        /// Specify the webroot directory to be used by the web host.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="webRoot">Path to the root directory used by the web server.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseWebRoot(this IWebHostBuilder hostBuilder, string webRoot)
-        {
-            if (webRoot == null)
-            {
-                throw new ArgumentNullException(nameof(webRoot));
-            }
-
-            return hostBuilder.UseSetting(WebHostDefaults.WebRootKey, webRoot);
-        }
-
-        /// <summary>
-        /// Specify the urls the web host will listen on.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
-        /// <param name="urls">The urls the hosted application will listen on.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder UseUrls(this IWebHostBuilder hostBuilder, params string[] urls)
-        {
-            if (urls == null)
-            {
-                throw new ArgumentNullException(nameof(urls));
-            }
-
-            return hostBuilder.UseSetting(WebHostDefaults.ServerUrlsKey, string.Join(ServerUrlsSeparator, urls));
-        }
-
-        /// <summary>
-        /// Start the web host and listen on the speficied urls.
-        /// </summary>
-        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to start.</param>
-        /// <param name="urls">The urls the hosted application will listen on.</param>
-        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHost Start(this IWebHostBuilder hostBuilder, params string[] urls)
-        {
-            var host = hostBuilder.UseUrls(urls).Build();
-            host.Start();
-            return host;
-        }
     }
-}
+}
\ No newline at end of file