diff --git a/benchmarks/Microsoft.AspNetCore.SignalR.Microbenchmarks/HubConnectionContextBenchmark.cs b/benchmarks/Microsoft.AspNetCore.SignalR.Microbenchmarks/HubConnectionContextBenchmark.cs
index 0f13aba113..d4182297cf 100644
--- a/benchmarks/Microsoft.AspNetCore.SignalR.Microbenchmarks/HubConnectionContextBenchmark.cs
+++ b/benchmarks/Microsoft.AspNetCore.SignalR.Microbenchmarks/HubConnectionContextBenchmark.cs
@@ -9,7 +9,6 @@ using System.Threading;
 using System.Threading.Tasks;
 using BenchmarkDotNet.Attributes;
 using Microsoft.AspNetCore.Connections;
-using Microsoft.AspNetCore.SignalR.Core;
 using Microsoft.AspNetCore.SignalR.Internal;
 using Microsoft.AspNetCore.Internal;
 using Microsoft.AspNetCore.SignalR.Protocol;
diff --git a/src/Microsoft.AspNetCore.SignalR.Core/DefaultUserIdProvider.cs b/src/Microsoft.AspNetCore.SignalR.Core/DefaultUserIdProvider.cs
index 6d04744284..194f527b02 100644
--- a/src/Microsoft.AspNetCore.SignalR.Core/DefaultUserIdProvider.cs
+++ b/src/Microsoft.AspNetCore.SignalR.Core/DefaultUserIdProvider.cs
@@ -3,11 +3,11 @@
 
 using System.Security.Claims;
 
-namespace Microsoft.AspNetCore.SignalR.Core
+namespace Microsoft.AspNetCore.SignalR
 {
     public class DefaultUserIdProvider : IUserIdProvider
     {
-        public string GetUserId(HubConnectionContext connection)
+        public virtual string GetUserId(HubConnectionContext connection)
         {
             return connection.User?.FindFirst(ClaimTypes.NameIdentifier)?.Value;
         }
diff --git a/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionContext.cs b/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionContext.cs
index 9724db8259..3e909ce3d0 100644
--- a/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionContext.cs
+++ b/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionContext.cs
@@ -14,7 +14,6 @@ using System.Threading.Tasks;
 using Microsoft.AspNetCore.Connections;
 using Microsoft.AspNetCore.Connections.Features;
 using Microsoft.AspNetCore.Http.Features;
-using Microsoft.AspNetCore.SignalR.Core;
 using Microsoft.AspNetCore.SignalR.Internal;
 using Microsoft.AspNetCore.SignalR.Protocol;
 using Microsoft.Extensions.Logging;
diff --git a/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionHandler.cs b/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionHandler.cs
index e9bcbf64bb..170461656a 100644
--- a/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionHandler.cs
+++ b/src/Microsoft.AspNetCore.SignalR.Core/HubConnectionHandler.cs
@@ -6,7 +6,6 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Connections;
-using Microsoft.AspNetCore.SignalR.Core;
 using Microsoft.AspNetCore.SignalR.Internal;
 using Microsoft.AspNetCore.SignalR.Protocol;
 using Microsoft.Extensions.Logging;
diff --git a/src/Microsoft.AspNetCore.SignalR.Core/IUserIdProvider.cs b/src/Microsoft.AspNetCore.SignalR.Core/IUserIdProvider.cs
index 227047fbf8..c2ff572a09 100644
--- a/src/Microsoft.AspNetCore.SignalR.Core/IUserIdProvider.cs
+++ b/src/Microsoft.AspNetCore.SignalR.Core/IUserIdProvider.cs
@@ -1,7 +1,7 @@
 // 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.
 
-namespace Microsoft.AspNetCore.SignalR.Core
+namespace Microsoft.AspNetCore.SignalR
 {
     public interface IUserIdProvider
     {
diff --git a/src/Microsoft.AspNetCore.SignalR.Core/SignalRDependencyInjectionExtensions.cs b/src/Microsoft.AspNetCore.SignalR.Core/SignalRDependencyInjectionExtensions.cs
index 78a6266b4d..0705ec933d 100644
--- a/src/Microsoft.AspNetCore.SignalR.Core/SignalRDependencyInjectionExtensions.cs
+++ b/src/Microsoft.AspNetCore.SignalR.Core/SignalRDependencyInjectionExtensions.cs
@@ -2,7 +2,6 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using Microsoft.AspNetCore.SignalR;
-using Microsoft.AspNetCore.SignalR.Core;
 using Microsoft.AspNetCore.SignalR.Internal;
 
 namespace Microsoft.Extensions.DependencyInjection