diff --git a/CryptoExchange.Net.UnitTests/BaseClientTests.cs b/CryptoExchange.Net.UnitTests/BaseClientTests.cs
index bf43577..c109479 100644
--- a/CryptoExchange.Net.UnitTests/BaseClientTests.cs
+++ b/CryptoExchange.Net.UnitTests/BaseClientTests.cs
@@ -23,7 +23,7 @@ namespace CryptoExchange.Net.UnitTests
             // arrange
             // act
             // assert
-            Assert.Throws(typeof(ArgumentException), () => new TestBaseClient(new RestClientOptions() { ApiCredentials = new ApiCredentials(key, secret) }));
+            Assert.Throws(typeof(ArgumentException), () => new TestBaseClient(new RestClientOptions("") { ApiCredentials = new ApiCredentials(key, secret) }));
         }
 
         [TestCase]
@@ -31,7 +31,7 @@ namespace CryptoExchange.Net.UnitTests
         {
             // arrange
             var stringBuilder = new StringBuilder();
-            var client = new TestBaseClient(new RestClientOptions()
+            var client = new TestBaseClient(new RestClientOptions("")
             {
                 LogWriters = new List<TextWriter> { new StringWriter(stringBuilder) }
             });
@@ -67,7 +67,7 @@ namespace CryptoExchange.Net.UnitTests
         {
             // arrange
             var stringBuilder = new StringBuilder();
-            var client = new TestBaseClient(new RestClientOptions()
+            var client = new TestBaseClient(new RestClientOptions("")
             {
                 LogWriters = new List<TextWriter> { new StringWriter(stringBuilder) },
                 LogVerbosity = verbosity
diff --git a/CryptoExchange.Net.UnitTests/RestClientTests.cs b/CryptoExchange.Net.UnitTests/RestClientTests.cs
index 78fa402..963e4f4 100644
--- a/CryptoExchange.Net.UnitTests/RestClientTests.cs
+++ b/CryptoExchange.Net.UnitTests/RestClientTests.cs
@@ -9,6 +9,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
+using System.Net.Http;
 using System.Text;
 using CryptoExchange.Net.Interfaces;
 using CryptoExchange.Net.RateLimiter;
@@ -105,7 +106,7 @@ namespace CryptoExchange.Net.UnitTests
         {
             // arrange
             // act
-            var client = new TestRestClient(new RestClientOptions()
+            var client = new TestRestClient(new RestClientOptions("")
             {
                 BaseAddress = "http://test.address.com",
                 RateLimiters = new List<IRateLimiter>{new RateLimiterTotal(1, TimeSpan.FromSeconds(1))},
@@ -123,7 +124,7 @@ namespace CryptoExchange.Net.UnitTests
         public void SettingRateLimitingBehaviourToFail_Should_FailLimitedRequests()
         {
             // arrange
-            var client = new TestRestClient(new RestClientOptions()
+            var client = new TestRestClient(new RestClientOptions("")
             {
                 RateLimiters = new List<IRateLimiter> { new RateLimiterTotal(1, TimeSpan.FromSeconds(1)) },
                 RateLimitingBehaviour = RateLimitingBehaviour.Fail
@@ -146,7 +147,7 @@ namespace CryptoExchange.Net.UnitTests
         public void SettingRateLimitingBehaviourToWait_Should_DelayLimitedRequests()
         {
             // arrange
-            var client = new TestRestClient(new RestClientOptions()
+            var client = new TestRestClient(new RestClientOptions("")
             {
                 RateLimiters = new List<IRateLimiter> { new RateLimiterTotal(1, TimeSpan.FromSeconds(1)) },
                 RateLimitingBehaviour = RateLimitingBehaviour.Wait
@@ -171,7 +172,7 @@ namespace CryptoExchange.Net.UnitTests
         public void SettingApiKeyRateLimiter_Should_DelayRequestsFromSameKey()
         {
             // arrange
-            var client = new TestRestClient(new RestClientOptions()
+            var client = new TestRestClient(new RestClientOptions("")
             {
                 RateLimiters = new List<IRateLimiter> { new RateLimiterAPIKey(1, TimeSpan.FromSeconds(1)) },
                 RateLimitingBehaviour = RateLimitingBehaviour.Wait,
diff --git a/CryptoExchange.Net.UnitTests/SocketClientTests.cs b/CryptoExchange.Net.UnitTests/SocketClientTests.cs
index 42c7ae1..e7d4049 100644
--- a/CryptoExchange.Net.UnitTests/SocketClientTests.cs
+++ b/CryptoExchange.Net.UnitTests/SocketClientTests.cs
@@ -19,7 +19,7 @@ namespace CryptoExchange.Net.UnitTests
         {
             //arrange
             //act
-            var client = new TestSocketClient(new SocketClientOptions()
+            var client = new TestSocketClient(new SocketClientOptions("")
             {
                 BaseAddress = "http://test.address.com",
                 ReconnectInterval = TimeSpan.FromSeconds(6)
@@ -51,7 +51,7 @@ namespace CryptoExchange.Net.UnitTests
         public void SocketMessages_Should_BeProcessedInDataHandlers()
         {
             // arrange
-            var client = new TestSocketClient(new SocketClientOptions() { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
+            var client = new TestSocketClient(new SocketClientOptions("") { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
             var socket = client.CreateSocket();
             socket.ShouldReconnect = true;
             socket.CanConnect = true;
@@ -59,11 +59,11 @@ namespace CryptoExchange.Net.UnitTests
             var sub = new SocketConnection(client, socket);
             var rstEvent = new ManualResetEvent(false);
             JToken result = null;
-            sub.AddHandler("TestHandler", true, (connection, data) =>
+            sub.AddHandler(SocketSubscription.CreateForIdentifier("TestHandler", true, (connection, data) =>
             {
                 result = data;
                 rstEvent.Set();
-            });
+            }));
             client.ConnectSocketSub(sub);
 
             // act
@@ -79,7 +79,7 @@ namespace CryptoExchange.Net.UnitTests
         {
             // arrange
             bool reconnected = false;
-            var client = new TestSocketClient(new SocketClientOptions() { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
+            var client = new TestSocketClient(new SocketClientOptions("") { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
             var socket = client.CreateSocket();
             socket.ShouldReconnect = true;
             socket.CanConnect = true;
@@ -106,12 +106,12 @@ namespace CryptoExchange.Net.UnitTests
         public void UnsubscribingStream_Should_CloseTheSocket()
         {
             // arrange
-            var client = new TestSocketClient(new SocketClientOptions() { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
+            var client = new TestSocketClient(new SocketClientOptions("") { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
             var socket = client.CreateSocket();
             socket.CanConnect = true;
             var sub = new SocketConnection(client, socket);
             client.ConnectSocketSub(sub);
-            var ups = new UpdateSubscription(sub, new SocketSubscription("Test", null, true, (d, a) => {}));
+            var ups = new UpdateSubscription(sub, SocketSubscription.CreateForIdentifier("Test", true, (d, a) => {}));
 
             // act
             client.Unsubscribe(ups).Wait();
@@ -124,7 +124,7 @@ namespace CryptoExchange.Net.UnitTests
         public void UnsubscribingAll_Should_CloseAllSockets()
         {
             // arrange
-            var client = new TestSocketClient(new SocketClientOptions() { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
+            var client = new TestSocketClient(new SocketClientOptions("") { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
             var socket1 = client.CreateSocket();
             var socket2 = client.CreateSocket();
             socket1.CanConnect = true;
@@ -146,7 +146,7 @@ namespace CryptoExchange.Net.UnitTests
         public void FailingToConnectSocket_Should_ReturnError()
         {
             // arrange
-            var client = new TestSocketClient(new SocketClientOptions() { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
+            var client = new TestSocketClient(new SocketClientOptions("") { ReconnectInterval = TimeSpan.Zero, LogVerbosity = LogVerbosity.Debug });
             var socket = client.CreateSocket();
             socket.CanConnect = false;
             var sub = new SocketConnection(client, socket);
diff --git a/CryptoExchange.Net.UnitTests/TestImplementations/TestBaseClient.cs b/CryptoExchange.Net.UnitTests/TestImplementations/TestBaseClient.cs
index dc0cd25..9b36f42 100644
--- a/CryptoExchange.Net.UnitTests/TestImplementations/TestBaseClient.cs
+++ b/CryptoExchange.Net.UnitTests/TestImplementations/TestBaseClient.cs
@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Net.Http;
 using CryptoExchange.Net.Authentication;
 using CryptoExchange.Net.Logging;
 using CryptoExchange.Net.Objects;
@@ -7,7 +8,7 @@ namespace CryptoExchange.Net.UnitTests
 {
     public class TestBaseClient: BaseClient
     {       
-        public TestBaseClient(): base(new RestClientOptions(), null)
+        public TestBaseClient(): base(new RestClientOptions("http://testurl.url"), null)
         {
         }
 
@@ -37,12 +38,12 @@ namespace CryptoExchange.Net.UnitTests
         {
         }
 
-        public override Dictionary<string, string> AddAuthenticationToHeaders(string uri, string method, Dictionary<string, object> parameters, bool signed)
+        public override Dictionary<string, string> AddAuthenticationToHeaders(string uri, HttpMethod method, Dictionary<string, object> parameters, bool signed)
         {
             return base.AddAuthenticationToHeaders(uri, method, parameters, signed);
         }
 
-        public override Dictionary<string, object> AddAuthenticationToParameters(string uri, string method, Dictionary<string, object> parameters, bool signed)
+        public override Dictionary<string, object> AddAuthenticationToParameters(string uri, HttpMethod method, Dictionary<string, object> parameters, bool signed)
         {
             return base.AddAuthenticationToParameters(uri, method, parameters, signed);
         }
diff --git a/CryptoExchange.Net.UnitTests/TestImplementations/TestRestClient.cs b/CryptoExchange.Net.UnitTests/TestImplementations/TestRestClient.cs
index e8bf674..8364895 100644
--- a/CryptoExchange.Net.UnitTests/TestImplementations/TestRestClient.cs
+++ b/CryptoExchange.Net.UnitTests/TestImplementations/TestRestClient.cs
@@ -7,8 +7,10 @@ using System.Collections.Generic;
 using System.IO;
 using System.Net;
 using System.Net.Http;
+using System.Net.Http.Headers;
 using System.Reflection;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using CryptoExchange.Net.Authentication;
 
@@ -16,7 +18,7 @@ namespace CryptoExchange.Net.UnitTests.TestImplementations
 {
     public class TestRestClient: RestClient
     {
-        public TestRestClient() : base(new RestClientOptions(), null)
+        public TestRestClient() : base(new RestClientOptions("http://testurl.url"), null)
         {
             RequestFactory = new Mock<IRequestFactory>().Object;
         }
@@ -39,36 +41,28 @@ namespace CryptoExchange.Net.UnitTests.TestImplementations
             responseStream.Seek(0, SeekOrigin.Begin);
 
             var response = new Mock<IResponse>();
-            response.Setup(c => c.GetResponseStream()).Returns(responseStream);
-
+            response.Setup(c => c.IsSuccessStatusCode).Returns(true);
+            response.Setup(c => c.GetResponseStream()).Returns(Task.FromResult((Stream)responseStream));
+            
             var request = new Mock<IRequest>();
-            request.Setup(c => c.Headers).Returns(new WebHeaderCollection());
             request.Setup(c => c.Uri).Returns(new Uri("http://www.test.com"));
-            request.Setup(c => c.GetRequestStream()).Returns(Task.FromResult(requestStream));
-            request.Setup(c => c.GetResponse()).Returns(Task.FromResult(response.Object));
+            request.Setup(c => c.GetResponse(It.IsAny<CancellationToken>())).Returns(Task.FromResult(response.Object));
 
             var factory = Mock.Get(RequestFactory);
-            factory.Setup(c => c.Create(It.IsAny<string>()))
+            factory.Setup(c => c.Create(It.IsAny<HttpMethod>(), It.IsAny<string>()))
                 .Returns(request.Object);
         }
 
         public void SetErrorWithoutResponse(HttpStatusCode code, string message)
         {
-            var we = new WebException();
-            var r = new HttpWebResponse();
-            var re = new HttpResponseMessage();
-
-            typeof(HttpResponseMessage).GetField("_statusCode", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).SetValue(re, code);
-            typeof(HttpWebResponse).GetField("_httpResponseMessage", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).SetValue(r, re);
-            typeof(WebException).GetField("_message", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).SetValue(we, message);
-            typeof(WebException).GetField("_response", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).SetValue(we, r);
-            
+            var we = new HttpRequestException();
+            typeof(HttpRequestException).GetField("_message", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance).SetValue(we, message);
+           
             var request = new Mock<IRequest>();
-            request.Setup(c => c.Headers).Returns(new WebHeaderCollection());
-            request.Setup(c => c.GetResponse()).Throws(we);
+            request.Setup(c => c.GetResponse(It.IsAny<CancellationToken>())).Throws(we);
 
             var factory = Mock.Get(RequestFactory);
-            factory.Setup(c => c.Create(It.IsAny<string>()))
+            factory.Setup(c => c.Create(It.IsAny<HttpMethod>(), It.IsAny<string>()))
                 .Returns(request.Object);
         }
 
@@ -79,22 +73,22 @@ namespace CryptoExchange.Net.UnitTests.TestImplementations
             responseStream.Write(expectedBytes, 0, expectedBytes.Length);
             responseStream.Seek(0, SeekOrigin.Begin);
 
-            var r = new Mock<HttpWebResponse>();
-            r.Setup(x => x.GetResponseStream()).Returns(responseStream);
-            var we = new WebException("", null, WebExceptionStatus.Success, r.Object);
-            
+            var response = new Mock<IResponse>();
+            response.Setup(c => c.IsSuccessStatusCode).Returns(false);
+            response.Setup(c => c.GetResponseStream()).Returns(Task.FromResult((Stream)responseStream));
+
             var request = new Mock<IRequest>();
-            request.Setup(c => c.Headers).Returns(new WebHeaderCollection());
-            request.Setup(c => c.GetResponse()).Throws(we);
+            request.Setup(c => c.Uri).Returns(new Uri("http://www.test.com"));
+            request.Setup(c => c.GetResponse(It.IsAny<CancellationToken>())).Returns(Task.FromResult(response.Object));
 
             var factory = Mock.Get(RequestFactory);
-            factory.Setup(c => c.Create(It.IsAny<string>()))
+            factory.Setup(c => c.Create(It.IsAny<HttpMethod>(), It.IsAny<string>()))
                 .Returns(request.Object);
         }
 
-        public async Task<CallResult<T>> Request<T>(string method = "GET") where T:class
+        public async Task<CallResult<T>> Request<T>(CancellationToken ct = default) where T:class
         {
-            return await ExecuteRequest<T>(new Uri("http://www.test.com"), method);
+            return await SendRequest<T>(new Uri("http://www.test.com"), HttpMethod.Get, ct);
         }
     }
 
diff --git a/CryptoExchange.Net.UnitTests/TestImplementations/TestSocketClient.cs b/CryptoExchange.Net.UnitTests/TestImplementations/TestSocketClient.cs
index d01dc94..43f18b9 100644
--- a/CryptoExchange.Net.UnitTests/TestImplementations/TestSocketClient.cs
+++ b/CryptoExchange.Net.UnitTests/TestImplementations/TestSocketClient.cs
@@ -11,7 +11,7 @@ namespace CryptoExchange.Net.UnitTests.TestImplementations
 {
     public class TestSocketClient: SocketClient
     {
-        public TestSocketClient() : this(new SocketClientOptions())
+        public TestSocketClient() : this(new SocketClientOptions("http://testurl.url"))
         {
         }
 
@@ -32,32 +32,33 @@ namespace CryptoExchange.Net.UnitTests.TestImplementations
             return ConnectSocket(sub).Result;
         }
 
-        protected override bool HandleQueryResponse<T>(SocketConnection s, object request, JToken data, out CallResult<T> callResult)
+        protected internal override bool HandleQueryResponse<T>(SocketConnection s, object request, JToken data, out CallResult<T> callResult)
         {
             throw new NotImplementedException();
         }
 
-        protected override bool HandleSubscriptionResponse(SocketConnection s, SocketSubscription subscription, object request, JToken message, out CallResult<object> callResult)
+        protected internal override bool HandleSubscriptionResponse(SocketConnection s, SocketSubscription subscription, object request, JToken message,
+            out CallResult<object> callResult)
         {
             throw new NotImplementedException();
         }
 
-        protected override bool MessageMatchesHandler(JToken message, object request)
+        protected internal override bool MessageMatchesHandler(JToken message, object request)
         {
             throw new NotImplementedException();
         }
 
-        protected override bool MessageMatchesHandler(JToken message, string identifier)
+        protected internal override bool MessageMatchesHandler(JToken message, string identifier)
         {
             return true;
         }
 
-        protected override Task<CallResult<bool>> AuthenticateSocket(SocketConnection s)
+        protected internal override Task<CallResult<bool>> AuthenticateSocket(SocketConnection s)
         {
             throw new NotImplementedException();
         }
 
-        protected override Task<bool> Unsubscribe(SocketConnection connection, SocketSubscription s)
+        protected internal override Task<bool> Unsubscribe(SocketConnection connection, SocketSubscription s)
         {
             throw new NotImplementedException();
         }
diff --git a/CryptoExchange.Net/AssemblyInfo.cs b/CryptoExchange.Net/AssemblyInfo.cs
new file mode 100644
index 0000000..987163f
--- /dev/null
+++ b/CryptoExchange.Net/AssemblyInfo.cs
@@ -0,0 +1 @@
+[assembly: System.Runtime.CompilerServices.InternalsVisibleTo("CryptoExchange.Net.UnitTests")]
\ No newline at end of file
diff --git a/CryptoExchange.Net/Attributes/NullableAttributes.cs b/CryptoExchange.Net/Attributes/NullableAttributes.cs
new file mode 100644
index 0000000..cb75272
--- /dev/null
+++ b/CryptoExchange.Net/Attributes/NullableAttributes.cs
@@ -0,0 +1,210 @@
+#if !NETSTANDARD2_1
+namespace System.Diagnostics.CodeAnalysis
+{
+    using global::System;
+
+    /// <summary>
+    ///     Specifies that <see langword="null"/> is allowed as an input even if the
+    ///     corresponding type disallows it.
+    /// </summary>
+    [AttributeUsage(
+        AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property,
+        Inherited = false
+    )]
+    [ExcludeFromCodeCoverage]
+    internal sealed class AllowNullAttribute : Attribute
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="AllowNullAttribute"/> class.
+        /// </summary>
+        public AllowNullAttribute() { }
+    }
+
+    /// <summary>
+    ///     Specifies that <see langword="null"/> is disallowed as an input even if the
+    ///     corresponding type allows it.
+    /// </summary>
+    [AttributeUsage(
+        AttributeTargets.Field | AttributeTargets.Parameter | AttributeTargets.Property,
+        Inherited = false
+    )]
+
+    [ExcludeFromCodeCoverage]
+    internal sealed class DisallowNullAttribute : Attribute
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="DisallowNullAttribute"/> class.
+        /// </summary>
+        public DisallowNullAttribute() { }
+    }
+
+    /// <summary>
+    ///     Specifies that a method that will never return under any circumstance.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+    [ExcludeFromCodeCoverage]
+    internal sealed class DoesNotReturnAttribute : Attribute
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="DoesNotReturnAttribute"/> class.
+        /// </summary>
+        public DoesNotReturnAttribute() { }
+    }
+
+    /// <summary>
+    ///     Specifies that the method will not return if the associated <see cref="Boolean"/>
+    ///     parameter is passed the specified value.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
+    [ExcludeFromCodeCoverage]
+    internal sealed class DoesNotReturnIfAttribute : Attribute
+    {
+        /// <summary>
+        ///     Gets the condition parameter value.
+        ///     Code after the method is considered unreachable by diagnostics if the argument
+        ///     to the associated parameter matches this value.
+        /// </summary>
+        public bool ParameterValue { get; }
+
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="DoesNotReturnIfAttribute"/>
+        ///     class with the specified parameter value.
+        /// </summary>
+        /// <param name="parameterValue">
+        ///     The condition parameter value.
+        ///     Code after the method is considered unreachable by diagnostics if the argument
+        ///     to the associated parameter matches this value.
+        /// </param>
+        public DoesNotReturnIfAttribute(bool parameterValue)
+        {
+            ParameterValue = parameterValue;
+        }
+    }
+
+    /// <summary>
+    ///     Specifies that an output may be <see langword="null"/> even if the
+    ///     corresponding type disallows it.
+    /// </summary>
+    [AttributeUsage(
+        AttributeTargets.Field | AttributeTargets.Parameter |
+        AttributeTargets.Property | AttributeTargets.ReturnValue,
+        Inherited = false
+    )]
+    [ExcludeFromCodeCoverage]
+    internal sealed class MaybeNullAttribute : Attribute
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="MaybeNullAttribute"/> class.
+        /// </summary>
+        public MaybeNullAttribute() { }
+    }
+
+    /// <summary>
+    ///     Specifies that when a method returns <see cref="ReturnValue"/>, 
+    ///     the parameter may be <see langword="null"/> even if the corresponding type disallows it.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
+    [ExcludeFromCodeCoverage]
+    internal sealed class MaybeNullWhenAttribute : Attribute
+    {
+        /// <summary>
+        ///     Gets the return value condition.
+        ///     If the method returns this value, the associated parameter may be <see langword="null"/>.
+        /// </summary>
+        public bool ReturnValue { get; }
+
+        /// <summary>
+        ///      Initializes the attribute with the specified return value condition.
+        /// </summary>
+        /// <param name="returnValue">
+        ///     The return value condition.
+        ///     If the method returns this value, the associated parameter may be <see langword="null"/>.
+        /// </param>
+        public MaybeNullWhenAttribute(bool returnValue)
+        {
+            ReturnValue = returnValue;
+        }
+    }
+
+    /// <summary>
+    ///     Specifies that an output is not <see langword="null"/> even if the
+    ///     corresponding type allows it.
+    /// </summary>
+    [AttributeUsage(
+        AttributeTargets.Field | AttributeTargets.Parameter |
+        AttributeTargets.Property | AttributeTargets.ReturnValue,
+        Inherited = false
+    )]
+    [ExcludeFromCodeCoverage]
+    internal sealed class NotNullAttribute : Attribute
+    {
+        /// <summary>
+        ///     Initializes a new instance of the <see cref="NotNullAttribute"/> class.
+        /// </summary>
+        public NotNullAttribute() { }
+    }
+
+    /// <summary>
+    ///     Specifies that the output will be non-<see langword="null"/> if the
+    ///     named parameter is non-<see langword="null"/>.
+    /// </summary>
+    [AttributeUsage(
+        AttributeTargets.Parameter | AttributeTargets.Property | AttributeTargets.ReturnValue,
+        AllowMultiple = true,
+        Inherited = false
+    )]
+    [ExcludeFromCodeCoverage]
+    internal sealed class NotNullIfNotNullAttribute : Attribute
+    {
+        /// <summary>
+        ///     Gets the associated parameter name.
+        ///     The output will be non-<see langword="null"/> if the argument to the
+        ///     parameter specified is non-<see langword="null"/>.
+        /// </summary>
+        public string ParameterName { get; }
+
+        /// <summary>
+        ///     Initializes the attribute with the associated parameter name.
+        /// </summary>
+        /// <param name="parameterName">
+        ///     The associated parameter name.
+        ///     The output will be non-<see langword="null"/> if the argument to the
+        ///     parameter specified is non-<see langword="null"/>.
+        /// </param>
+        public NotNullIfNotNullAttribute(string parameterName)
+        {
+            // .NET Core 3.0 doesn't throw an ArgumentNullException, even though this is
+            // tagged as non-null.
+            // Follow this behavior here.
+            ParameterName = parameterName;
+        }
+    }
+
+    /// <summary>
+    ///     Specifies that when a method returns <see cref="ReturnValue"/>,
+    ///     the parameter will not be <see langword="null"/> even if the corresponding type allows it.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
+    [ExcludeFromCodeCoverage]
+    internal sealed class NotNullWhenAttribute : Attribute
+    {
+        /// <summary>
+        ///     Gets the return value condition.
+        ///     If the method returns this value, the associated parameter will not be <see langword="null"/>.
+        /// </summary>
+        public bool ReturnValue { get; }
+
+        /// <summary>
+        ///     Initializes the attribute with the specified return value condition.
+        /// </summary>
+        /// <param name="returnValue">
+        ///     The return value condition.
+        ///     If the method returns this value, the associated parameter will not be <see langword="null"/>.
+        /// </param>
+        public NotNullWhenAttribute(bool returnValue)
+        {
+            ReturnValue = returnValue;
+        }
+    }
+}
+#endif
\ No newline at end of file
diff --git a/CryptoExchange.Net/BaseClient.cs b/CryptoExchange.Net/BaseClient.cs
index 699f349..aa475b6 100644
--- a/CryptoExchange.Net/BaseClient.cs
+++ b/CryptoExchange.Net/BaseClient.cs
@@ -10,6 +10,7 @@ using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Text;
 using System.Threading.Tasks;
 
 namespace CryptoExchange.Net
@@ -22,7 +23,7 @@ namespace CryptoExchange.Net
         /// <summary>
         /// The address of the client
         /// </summary>
-        public string BaseAddress { get; private set; }
+        public string BaseAddress { get; }
         /// <summary>
         /// The log object
         /// </summary>
@@ -207,36 +208,39 @@ namespace CryptoExchange.Net
 
             try
             {
-                using var reader = new StreamReader(stream);
+                using var reader = new StreamReader(stream, Encoding.UTF8, false, 512, true);
                 using var jsonReader = new JsonTextReader(reader);
                 return new CallResult<T>(serializer.Deserialize<T>(jsonReader), null);
             }
             catch (JsonReaderException jre)
             {
+                if(stream.CanSeek)
+                    stream.Seek(0, SeekOrigin.Begin);
                 var data = await ReadStream(stream).ConfigureAwait(false);
-                var info = $"Deserialize JsonReaderException: {jre.Message}, Path: {jre.Path}, LineNumber: {jre.LineNumber}, LinePosition: {jre.LinePosition}, data: {data}";
-                log.Write(LogVerbosity.Error, info);
-                return new CallResult<T>(default, new DeserializeError(info));
+                log.Write(LogVerbosity.Error, $"Deserialize JsonReaderException: {jre.Message}, Path: {jre.Path}, LineNumber: {jre.LineNumber}, LinePosition: {jre.LinePosition}, data: {data}");
+                return new CallResult<T>(default, new DeserializeError(data));
             }
             catch (JsonSerializationException jse)
             {
+                if (stream.CanSeek)
+                    stream.Seek(0, SeekOrigin.Begin);
                 var data = await ReadStream(stream).ConfigureAwait(false);
-                var info = $"Deserialize JsonSerializationException: {jse.Message}, data: {data}";
-                log.Write(LogVerbosity.Error, info);
-                return new CallResult<T>(default, new DeserializeError(info));
+                log.Write(LogVerbosity.Error, $"Deserialize JsonSerializationException: {jse.Message}, data: {data}");
+                return new CallResult<T>(default, new DeserializeError(data));
             }
             catch (Exception ex)
             {
+                if (stream.CanSeek)
+                    stream.Seek(0, SeekOrigin.Begin);
                 var data = await ReadStream(stream).ConfigureAwait(false);
-                var info = $"Deserialize Unknown Exception: {ex.Message}, data: {data}";
-                log.Write(LogVerbosity.Error, info);
-                return new CallResult<T>(default, new DeserializeError(info));
+                log.Write(LogVerbosity.Error, $"Deserialize Unknown Exception: {ex.Message}, data: {data}");
+                return new CallResult<T>(default, new DeserializeError(data));
             }
         }
 
         private async Task<string> ReadStream(Stream stream)
-        {
-            using var reader = new StreamReader(stream);
+        { 
+            using var reader = new StreamReader(stream, Encoding.UTF8, false, 512, true);
             return await reader.ReadToEndAsync().ConfigureAwait(false);
         }
 
diff --git a/CryptoExchange.Net/Converters/BaseConverter.cs b/CryptoExchange.Net/Converters/BaseConverter.cs
index 97f18d0..da8e3d5 100644
--- a/CryptoExchange.Net/Converters/BaseConverter.cs
+++ b/CryptoExchange.Net/Converters/BaseConverter.cs
@@ -70,7 +70,7 @@ namespace CryptoExchange.Net.Converters
             return objectType == typeof(T) || Nullable.GetUnderlyingType(objectType) == typeof(T);
         }
 
-        private bool GetValue(string value, [NotNullWhen(false)]out T result)
+        private bool GetValue(string value, out T result)
         {
             var mapping = Mapping.FirstOrDefault(kv => kv.Value.Equals(value, StringComparison.InvariantCultureIgnoreCase));
             if (!mapping.Equals(default(KeyValuePair<T, string>)))
diff --git a/CryptoExchange.Net/CryptoExchange.Net.csproj b/CryptoExchange.Net/CryptoExchange.Net.csproj
index 783ef3e..99af2ea 100644
--- a/CryptoExchange.Net/CryptoExchange.Net.csproj
+++ b/CryptoExchange.Net/CryptoExchange.Net.csproj
@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>netstandard2.1</TargetFramework>
+    <TargetFrameworks>netstandard2.0;netstandard2.1</TargetFrameworks>
   </PropertyGroup>  
   <PropertyGroup>
     <PackageId>CryptoExchange.Net</PackageId>
@@ -8,12 +8,12 @@
     <PackageVersion>2.1.8</PackageVersion>
     <PackageRequireLicenseAcceptance>false</PackageRequireLicenseAcceptance>
     <PackageProjectUrl>https://github.com/JKorf/CryptoExchange.Net</PackageProjectUrl>
-    <PackageLicenseUrl>https://github.com/JKorf/CryptoExchange.Net/blob/master/LICENSE</PackageLicenseUrl>
     <NeutralLanguage>en</NeutralLanguage>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <PackageReleaseNotes>2.1.8 - Added array serialization options for implementations</PackageReleaseNotes>
     <Nullable>enable</Nullable>
 	<LangVersion>8.0</LangVersion>
+	<PackageLicenseExpression>MIT</PackageLicenseExpression>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
     <DocumentationFile>CryptoExchange.Net.xml</DocumentationFile>
diff --git a/CryptoExchange.Net/CryptoExchange.Net.xml b/CryptoExchange.Net/CryptoExchange.Net.xml
index 0a8433e..d71e803 100644
--- a/CryptoExchange.Net/CryptoExchange.Net.xml
+++ b/CryptoExchange.Net/CryptoExchange.Net.xml
@@ -536,11 +536,6 @@
             Content
             </summary>
         </member>
-        <member name="P:CryptoExchange.Net.Interfaces.IRequest.Headers">
-            <summary>
-            Headers
-            </summary>
-        </member>
         <member name="P:CryptoExchange.Net.Interfaces.IRequest.Method">
             <summary>
             Method
@@ -564,6 +559,13 @@
             <param name="data"></param>
             <param name="contentType"></param>
         </member>
+        <member name="M:CryptoExchange.Net.Interfaces.IRequest.AddHeader(System.String,System.String)">
+            <summary>
+            Add a header to the request
+            </summary>
+            <param name="key"></param>
+            <param name="value"></param>
+        </member>
         <member name="M:CryptoExchange.Net.Interfaces.IRequest.GetResponse(System.Threading.CancellationToken)">
             <summary>
             Get the response
@@ -663,13 +665,13 @@
             Removes all rate limiters from this client
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Interfaces.IRestClient.Ping">
+        <member name="M:CryptoExchange.Net.Interfaces.IRestClient.Ping(System.Threading.CancellationToken)">
             <summary>
             Ping to see if the server is reachable
             </summary>
             <returns>The roundtrip time of the ping request</returns>
         </member>
-        <member name="M:CryptoExchange.Net.Interfaces.IRestClient.PingAsync">
+        <member name="M:CryptoExchange.Net.Interfaces.IRestClient.PingAsync(System.Threading.CancellationToken)">
             <summary>
             Ping to see if the server is reachable
             </summary>
@@ -700,6 +702,20 @@
             The base address of the API
             </summary>
         </member>
+        <member name="P:CryptoExchange.Net.Interfaces.ISocketClient.ResponseTimeout">
+            <inheritdoc cref="P:CryptoExchange.Net.Objects.SocketClientOptions.SocketResponseTimeout"/>
+        </member>
+        <member name="P:CryptoExchange.Net.Interfaces.ISocketClient.SocketNoDataTimeout">
+            <inheritdoc cref="P:CryptoExchange.Net.Objects.SocketClientOptions.SocketNoDataTimeout"/>
+        </member>
+        <member name="P:CryptoExchange.Net.Interfaces.ISocketClient.MaxSocketConnections">
+            <summary>
+            The max amount of concurrent socket connections
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Interfaces.ISocketClient.SocketCombineTarget">
+            <inheritdoc cref="P:CryptoExchange.Net.Objects.SocketClientOptions.SocketSubscriptionsCombineTarget"/>
+        </member>
         <member name="M:CryptoExchange.Net.Interfaces.ISocketClient.Unsubscribe(CryptoExchange.Net.Sockets.UpdateSubscription)">
             <summary>
             Unsubscribe from a stream
@@ -1135,6 +1151,12 @@
             <param name="data"></param>
             <param name="error"></param>
         </member>
+        <member name="M:CryptoExchange.Net.Objects.CallResult`1.op_Implicit(CryptoExchange.Net.Objects.CallResult{`0})~System.Boolean">
+            <summary>
+            Overwrite bool check so we can use if(callResult) instead of if(callResult.Success)
+            </summary>
+            <param name="obj"></param>
+        </member>
         <member name="T:CryptoExchange.Net.Objects.WebCallResult`1">
             <summary>
             The result of a request
@@ -1306,12 +1328,18 @@
             The message for the error that occured
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.Error.#ctor(System.Int32,System.String)">
+        <member name="P:CryptoExchange.Net.Objects.Error.Data">
+            <summary>
+            Optional data for the error
+            </summary>
+        </member>
+        <member name="M:CryptoExchange.Net.Objects.Error.#ctor(System.Int32,System.String,System.Object)">
             <summary>
             ctor
             </summary>
             <param name="code"></param>
             <param name="message"></param>
+            <param name="data"></param>
         </member>
         <member name="M:CryptoExchange.Net.Objects.Error.ToString">
             <summary>
@@ -1344,51 +1372,53 @@
             Error returned by the server
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.ServerError.#ctor(System.String)">
+        <member name="M:CryptoExchange.Net.Objects.ServerError.#ctor(System.String,System.Object)">
             <summary>
             ctor
             </summary>
             <param name="message"></param>
+            <param name="data"></param>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.ServerError.#ctor(System.Int32,System.String)">
+        <member name="M:CryptoExchange.Net.Objects.ServerError.#ctor(System.Int32,System.String,System.Object)">
             <summary>
             ctor
             </summary>
             <param name="code"></param>
             <param name="message"></param>
+            <param name="data"></param>
         </member>
         <member name="T:CryptoExchange.Net.Objects.WebError">
             <summary>
             Web error returned by the server
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.WebError.#ctor(System.String)">
+        <member name="M:CryptoExchange.Net.Objects.WebError.#ctor(System.Object)">
             <summary>
             ctor
             </summary>
-            <param name="message"></param>
+            <param name="data"></param>
         </member>
         <member name="T:CryptoExchange.Net.Objects.DeserializeError">
             <summary>
             Error while deserializing data
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.DeserializeError.#ctor(System.String)">
+        <member name="M:CryptoExchange.Net.Objects.DeserializeError.#ctor(System.Object)">
             <summary>
             ctor
             </summary>
-            <param name="message"></param>
+            <param name="data">Deserializing data</param>
         </member>
         <member name="T:CryptoExchange.Net.Objects.UnknownError">
             <summary>
             Unknown error
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Objects.UnknownError.#ctor(System.String)">
+        <member name="M:CryptoExchange.Net.Objects.UnknownError.#ctor(System.Object)">
             <summary>
             ctor
             </summary>
-            <param name="message"></param>
+            <param name="data">Error data</param>
         </member>
         <member name="T:CryptoExchange.Net.Objects.ArgumentError">
             <summary>
@@ -1665,6 +1695,11 @@
             The bid list
             </summary>
         </member>
+        <member name="P:CryptoExchange.Net.OrderBook.SymbolOrderBook.Id">
+            <summary>
+            Order book implementation id
+            </summary>
+        </member>
         <member name="F:CryptoExchange.Net.OrderBook.SymbolOrderBook.log">
             <summary>
             The log
@@ -1910,9 +1945,6 @@
             <param name="request"></param>
             <param name="client"></param>
         </member>
-        <member name="P:CryptoExchange.Net.Requests.Request.Headers">
-            <inheritdoc />
-        </member>
         <member name="P:CryptoExchange.Net.Requests.Request.Content">
             <inheritdoc />
         </member>
@@ -1928,6 +1960,9 @@
         <member name="M:CryptoExchange.Net.Requests.Request.SetContent(System.String,System.String)">
             <inheritdoc />
         </member>
+        <member name="M:CryptoExchange.Net.Requests.Request.AddHeader(System.String,System.String)">
+            <inheritdoc />
+        </member>
         <member name="M:CryptoExchange.Net.Requests.Request.SetContent(System.Byte[])">
             <inheritdoc />
         </member>
@@ -2034,13 +2069,13 @@
             Removes all rate limiters from this client
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.RestClient.Ping">
+        <member name="M:CryptoExchange.Net.RestClient.Ping(System.Threading.CancellationToken)">
             <summary>
             Ping to see if the server is reachable
             </summary>
             <returns>The roundtrip time of the ping request</returns>
         </member>
-        <member name="M:CryptoExchange.Net.RestClient.PingAsync">
+        <member name="M:CryptoExchange.Net.RestClient.PingAsync(System.Threading.CancellationToken)">
             <summary>
             Ping to see if the server is reachable
             </summary>
@@ -2380,6 +2415,187 @@
             Socket implementation
             </summary>
         </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.socket">
+            <summary>
+            Socket
+            </summary>
+        </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.log">
+            <summary>
+            Log
+            </summary>
+        </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.errorHandlers">
+            <summary>
+            Error handlers
+            </summary>
+        </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.openHandlers">
+            <summary>
+            Open handlers
+            </summary>
+        </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.closeHandlers">
+            <summary>
+            Close handlers
+            </summary>
+        </member>
+        <member name="F:CryptoExchange.Net.Sockets.BaseSocket.messageHandlers">
+            <summary>
+            Message handlers
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.Id">
+            <summary>
+            Id
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.Reconnecting">
+            <summary>
+            If is reconnecting
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.Origin">
+            <summary>
+            Origin
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.Url">
+            <summary>
+            Url
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.IsClosed">
+            <summary>
+            Is closed
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.IsOpen">
+            <summary>
+            Is open
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.SSLProtocols">
+            <summary>
+            Protocols
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.DataInterpreterBytes">
+            <summary>
+            Interpreter for bytes
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.DataInterpreterString">
+            <summary>
+            Interpreter for strings
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.LastActionTime">
+            <summary>
+            Last action time
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.Timeout">
+            <summary>
+            Timeout
+            </summary>
+        </member>
+        <member name="P:CryptoExchange.Net.Sockets.BaseSocket.SocketState">
+            <summary>
+            Socket state
+            </summary>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.#ctor(CryptoExchange.Net.Logging.Log,System.String)">
+            <summary>
+            ctor
+            </summary>
+            <param name="log"></param>
+            <param name="url"></param>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.#ctor(CryptoExchange.Net.Logging.Log,System.String,System.Collections.Generic.IDictionary{System.String,System.String},System.Collections.Generic.IDictionary{System.String,System.String})">
+            <summary>
+            ctor
+            </summary>
+            <param name="log"></param>
+            <param name="url"></param>
+            <param name="cookies"></param>
+            <param name="headers"></param>
+        </member>
+        <member name="E:CryptoExchange.Net.Sockets.BaseSocket.OnClose">
+            <summary>
+            On close
+            </summary>
+        </member>
+        <member name="E:CryptoExchange.Net.Sockets.BaseSocket.OnMessage">
+            <summary>
+            On message
+            </summary>
+        </member>
+        <member name="E:CryptoExchange.Net.Sockets.BaseSocket.OnError">
+            <summary>
+            On error
+            </summary>
+        </member>
+        <member name="E:CryptoExchange.Net.Sockets.BaseSocket.OnOpen">
+            <summary>
+            On open
+            </summary>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Handle(System.Collections.Generic.List{System.Action})">
+            <summary>
+            Handle
+            </summary>
+            <param name="handlers"></param>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Handle``1(System.Collections.Generic.List{System.Action{``0}},``0)">
+            <summary>
+            Handle
+            </summary>
+            <typeparam name="T"></typeparam>
+            <param name="handlers"></param>
+            <param name="data"></param>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.CheckTimeout">
+            <summary>
+            Checks if timed out
+            </summary>
+            <returns></returns>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Close">
+            <summary>
+            Close socket
+            </summary>
+            <returns></returns>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Reset">
+            <summary>
+            Reset socket
+            </summary>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Send(System.String)">
+            <summary>
+            Send data
+            </summary>
+            <param name="data"></param>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Connect">
+            <summary>
+            Connect socket
+            </summary>
+            <returns></returns>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.SetProxy(System.String,System.Int32)">
+            <summary>
+            Set a proxy
+            </summary>
+            <param name="host"></param>
+            <param name="port"></param>
+        </member>
+        <member name="M:CryptoExchange.Net.Sockets.BaseSocket.Dispose">
+            <summary>
+            Dispose
+            </summary>
+        </member>
         <member name="T:CryptoExchange.Net.Sockets.SocketConnection">
             <summary>
             Socket connecting
@@ -2442,24 +2658,11 @@
             <param name="client">The socket client</param>
             <param name="socket">The socket</param>
         </member>
-        <member name="M:CryptoExchange.Net.Sockets.SocketConnection.AddHandler(System.Object,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
+        <member name="M:CryptoExchange.Net.Sockets.SocketConnection.AddHandler(CryptoExchange.Net.Sockets.SocketSubscription)">
             <summary>
-            Add a handler
+            Add handler
             </summary>
-            <param name="request">The request object</param>
-            <param name="userSubscription">If it is a user subscription or a generic handler</param>
-            <param name="dataHandler">The data handler</param>
-            <returns></returns>
-        </member>
-        <member name="M:CryptoExchange.Net.Sockets.SocketConnection.AddHandler(System.String,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
-            <summary>
-            Add a handler
-            </summary>
-            <param name="identifier">The identifier of the handler</param>
-            <param name="userSubscription">If it is a user subscription or a generic handler</param>
-            <param name="dataHandler">The data handler</param>
-            <returns></returns>
-            <returns></returns>
+            <param name="handler"></param>
         </member>
         <member name="M:CryptoExchange.Net.Sockets.SocketConnection.SendAndWait``1(``0,System.TimeSpan,System.Func{Newtonsoft.Json.Linq.JToken,System.Boolean})">
             <summary>
@@ -2538,21 +2741,23 @@
             If the subscription has been confirmed
             </summary>
         </member>
-        <member name="M:CryptoExchange.Net.Sockets.SocketSubscription.#ctor(System.Object,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
+        <member name="M:CryptoExchange.Net.Sockets.SocketSubscription.CreateForRequest(System.Object,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
             <summary>
-            ctor
+            Create SocketSubscription for a request
             </summary>
             <param name="request"></param>
             <param name="userSubscription"></param>
             <param name="dataHandler"></param>
+            <returns></returns>
         </member>
-        <member name="M:CryptoExchange.Net.Sockets.SocketSubscription.#ctor(System.String,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
+        <member name="M:CryptoExchange.Net.Sockets.SocketSubscription.CreateForIdentifier(System.String,System.Boolean,System.Action{CryptoExchange.Net.Sockets.SocketConnection,Newtonsoft.Json.Linq.JToken})">
             <summary>
-            ctor
+            Create SocketSubscription for an identifier
             </summary>
             <param name="identifier"></param>
             <param name="userSubscription"></param>
             <param name="dataHandler"></param>
+            <returns></returns>
         </member>
         <member name="M:CryptoExchange.Net.Sockets.SocketSubscription.InvokeExceptionHandler(System.Exception)">
             <summary>
diff --git a/CryptoExchange.Net/ExtensionMethods.cs b/CryptoExchange.Net/ExtensionMethods.cs
index b8133b4..116a904 100644
--- a/CryptoExchange.Net/ExtensionMethods.cs
+++ b/CryptoExchange.Net/ExtensionMethods.cs
@@ -131,7 +131,7 @@ namespace CryptoExchange.Net
         /// </summary>
         /// <param name="source"></param>
         /// <returns></returns>
-        internal static SecureString ToSecureString(this string source)
+        public static SecureString ToSecureString(this string source)
         {
             var secureString = new SecureString();
             foreach (var c in source)
diff --git a/CryptoExchange.Net/Interfaces/IRequest.cs b/CryptoExchange.Net/Interfaces/IRequest.cs
index 656a276..c8b9403 100644
--- a/CryptoExchange.Net/Interfaces/IRequest.cs
+++ b/CryptoExchange.Net/Interfaces/IRequest.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Threading;
@@ -20,10 +21,6 @@ namespace CryptoExchange.Net.Interfaces
         /// </summary>
         string? Content { get; }
         /// <summary>
-        /// Headers
-        /// </summary>
-        HttpRequestHeaders Headers { get; }
-        /// <summary>
         /// Method
         /// </summary>
         HttpMethod Method { get; set; }
@@ -42,6 +39,13 @@ namespace CryptoExchange.Net.Interfaces
         /// <param name="data"></param>
         /// <param name="contentType"></param>
         void SetContent(string data, string contentType);
+
+        /// <summary>
+        /// Add a header to the request
+        /// </summary>
+        /// <param name="key"></param>
+        /// <param name="value"></param>
+        void AddHeader(string key, string value);
         /// <summary>
         /// Get the response
         /// </summary>
diff --git a/CryptoExchange.Net/Interfaces/IRestClient.cs b/CryptoExchange.Net/Interfaces/IRestClient.cs
index c2f3b82..60d9e8b 100644
--- a/CryptoExchange.Net/Interfaces/IRestClient.cs
+++ b/CryptoExchange.Net/Interfaces/IRestClient.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Threading;
 using System.Threading.Tasks;
 using CryptoExchange.Net.Objects;
 using CryptoExchange.Net.RateLimiter;
@@ -51,12 +52,12 @@ namespace CryptoExchange.Net.Interfaces
         /// Ping to see if the server is reachable
         /// </summary>
         /// <returns>The roundtrip time of the ping request</returns>
-        CallResult<long> Ping();
+        CallResult<long> Ping(CancellationToken ct = default);
 
         /// <summary>
         /// Ping to see if the server is reachable
         /// </summary>
         /// <returns>The roundtrip time of the ping request</returns>
-        Task<CallResult<long>> PingAsync();
+        Task<CallResult<long>> PingAsync(CancellationToken ct = default);
     }
 }
\ No newline at end of file
diff --git a/CryptoExchange.Net/Interfaces/ISocketClient.cs b/CryptoExchange.Net/Interfaces/ISocketClient.cs
index 195b1ce..7cbacc9 100644
--- a/CryptoExchange.Net/Interfaces/ISocketClient.cs
+++ b/CryptoExchange.Net/Interfaces/ISocketClient.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Threading.Tasks;
+using CryptoExchange.Net.Objects;
 using CryptoExchange.Net.Sockets;
 
 namespace CryptoExchange.Net.Interfaces
@@ -29,6 +30,20 @@ namespace CryptoExchange.Net.Interfaces
         /// </summary>
         string BaseAddress { get; }
 
+        /// <inheritdoc cref="SocketClientOptions.SocketResponseTimeout"/>
+        TimeSpan ResponseTimeout { get; }
+
+        /// <inheritdoc cref="SocketClientOptions.SocketNoDataTimeout"/>
+        TimeSpan SocketNoDataTimeout { get; }
+
+        /// <summary>
+        /// The max amount of concurrent socket connections
+        /// </summary>
+        int MaxSocketConnections { get; }
+
+        /// <inheritdoc cref="SocketClientOptions.SocketSubscriptionsCombineTarget"/>
+        int SocketCombineTarget { get; }
+
         /// <summary>
         /// Unsubscribe from a stream
         /// </summary>
diff --git a/CryptoExchange.Net/Logging/ThreadSafeFileWriter.cs b/CryptoExchange.Net/Logging/ThreadSafeFileWriter.cs
index 97c6ce0..a9556dc 100644
--- a/CryptoExchange.Net/Logging/ThreadSafeFileWriter.cs
+++ b/CryptoExchange.Net/Logging/ThreadSafeFileWriter.cs
@@ -12,7 +12,7 @@ namespace CryptoExchange.Net.Logging
         private static readonly object openedFilesLock = new object();
         private static readonly List<string> openedFiles = new List<string>();
 
-        private StreamWriter logWriter;
+        private readonly StreamWriter logWriter;
         private readonly object writeLock;
 
         /// <inheritdoc />
diff --git a/CryptoExchange.Net/Objects/CallResult.cs b/CryptoExchange.Net/Objects/CallResult.cs
index 78044f4..9253ead 100644
--- a/CryptoExchange.Net/Objects/CallResult.cs
+++ b/CryptoExchange.Net/Objects/CallResult.cs
@@ -40,7 +40,7 @@ namespace CryptoExchange.Net.Objects
         /// <param name="obj"></param>
         public static implicit operator bool(CallResult<T> obj)
         {
-            return !ReferenceEquals(obj, null) && obj.Success;
+            return obj?.Success == true;
         }
     }
 
@@ -67,7 +67,9 @@ namespace CryptoExchange.Net.Objects
         /// <param name="responseHeaders"></param>
         /// <param name="data"></param>
         /// <param name="error"></param>
-        public WebCallResult(HttpStatusCode? code, IEnumerable<KeyValuePair<string, IEnumerable<string>>>? responseHeaders, [AllowNull] T data, Error? error): base(data, error)
+        public WebCallResult(
+            HttpStatusCode? code, 
+            IEnumerable<KeyValuePair<string, IEnumerable<string>>>? responseHeaders, [AllowNull] T data, Error? error): base(data, error)
         {
             ResponseHeaders = responseHeaders;
             ResponseStatusCode = code;
@@ -80,7 +82,7 @@ namespace CryptoExchange.Net.Objects
         /// <returns></returns>
         public static WebCallResult<T> CreateErrorResult(Error error)
         {
-            return new WebCallResult<T>(null, null, default, error);
+            return new WebCallResult<T>(null, null, default!, error);
         }
 
         /// <summary>
@@ -90,9 +92,9 @@ namespace CryptoExchange.Net.Objects
         /// <param name="responseHeaders"></param>
         /// <param name="error"></param>
         /// <returns></returns>
-        public static WebCallResult<T> CreateErrorResult(HttpStatusCode? code, IEnumerable<KeyValuePair<string, IEnumerable<string>>> responseHeaders, Error error)
+        public static WebCallResult<T> CreateErrorResult(HttpStatusCode? code, IEnumerable<KeyValuePair<string, IEnumerable<string>>>? responseHeaders, Error error)
         {
-            return new WebCallResult<T>(code, responseHeaders, default, error);
+            return new WebCallResult<T>(code, responseHeaders, default!, error);
         }
     }
 }
diff --git a/CryptoExchange.Net/Objects/Error.cs b/CryptoExchange.Net/Objects/Error.cs
index 0836d3e..0a4b838 100644
--- a/CryptoExchange.Net/Objects/Error.cs
+++ b/CryptoExchange.Net/Objects/Error.cs
@@ -14,15 +14,22 @@
         /// </summary>
         public string Message { get; set; }
 
+        /// <summary>
+        /// Optional data for the error
+        /// </summary>
+        public object? Data { get; set; }
+
         /// <summary>
         /// ctor
         /// </summary>
         /// <param name="code"></param>
         /// <param name="message"></param>
-        protected Error(int code, string message)
+        /// <param name="data"></param>
+        protected Error(int code, string message, object? data)
         {
             Code = code;
             Message = message;
+            Data = data;
         }
 
         /// <summary>
@@ -31,7 +38,7 @@
         /// <returns></returns>
         public override string ToString()
         {
-            return $"{Code}: {Message}";
+            return $"{Code}: {Message} {Data}";
         }
     }
 
@@ -43,7 +50,7 @@
         /// <summary>
         /// ctor
         /// </summary>
-        public CantConnectError() : base(1, "Can't connect to the server") { }
+        public CantConnectError() : base(1, "Can't connect to the server", null) { }
     }
 
     /// <summary>
@@ -54,7 +61,7 @@
         /// <summary>
         /// ctor
         /// </summary>
-        public NoApiCredentialsError() : base(2, "No credentials provided for private endpoint") { }
+        public NoApiCredentialsError() : base(2, "No credentials provided for private endpoint", null) { }
     }
 
     /// <summary>
@@ -66,14 +73,16 @@
         /// ctor
         /// </summary>
         /// <param name="message"></param>
-        public ServerError(string message) : base(3, "Server error: " + message) { }
+        /// <param name="data"></param>
+        public ServerError(string message, object? data = null) : base(3, "Server error: " + message, data) { }
 
         /// <summary>
         /// ctor
         /// </summary>
         /// <param name="code"></param>
         /// <param name="message"></param>
-        public ServerError(int code, string message) : base(code, message)
+        /// <param name="data"></param>
+        public ServerError(int code, string message, object? data = null) : base(code, message, data)
         {
         }
     }
@@ -86,8 +95,8 @@
         /// <summary>
         /// ctor
         /// </summary>
-        /// <param name="message"></param>
-        public WebError(string message) : base(4, "Web error: " + message) { }
+        /// <param name="data"></param>
+        public WebError(object? data) : base(4, "Web error", data) { }
     }
 
     /// <summary>
@@ -98,8 +107,8 @@
         /// <summary>
         /// ctor
         /// </summary>
-        /// <param name="message"></param>
-        public DeserializeError(string message) : base(5, "Error deserializing data: " + message) { }
+        /// <param name="data">Deserializing data</param>
+        public DeserializeError(object? data) : base(5, "Error deserializing data", data) { }
     }
 
     /// <summary>
@@ -110,8 +119,8 @@
         /// <summary>
         /// ctor
         /// </summary>
-        /// <param name="message"></param>
-        public UnknownError(string message) : base(6, "Unknown error occured " + message) { }
+        /// <param name="data">Error data</param>
+        public UnknownError(object? data = null) : base(6, "Unknown error occured", data) { }
     }
 
     /// <summary>
@@ -123,7 +132,7 @@
         /// ctor
         /// </summary>
         /// <param name="message"></param>
-        public ArgumentError(string message) : base(7, "Invalid parameter: " + message) { }
+        public ArgumentError(string message) : base(7, "Invalid parameter: " + message, null) { }
     }
 
     /// <summary>
@@ -135,7 +144,7 @@
         /// ctor
         /// </summary>
         /// <param name="message"></param>
-        public RateLimitError(string message) : base(8, "Rate limit exceeded: " + message) { }
+        public RateLimitError(string message) : base(8, "Rate limit exceeded: " + message, null) { }
     }
 
     /// <summary>
@@ -146,6 +155,6 @@
         /// <summary>
         /// ctor
         /// </summary>
-        public CancellationRequestedError() : base(9, "Cancellation requested") { }
+        public CancellationRequestedError() : base(9, "Cancellation requested", null) { }
     }
 }
diff --git a/CryptoExchange.Net/Objects/Options.cs b/CryptoExchange.Net/Objects/Options.cs
index e7e67c7..18744ab 100644
--- a/CryptoExchange.Net/Objects/Options.cs
+++ b/CryptoExchange.Net/Objects/Options.cs
@@ -153,7 +153,7 @@ namespace CryptoExchange.Net.Objects
         /// <inheritdoc />
         public override string ToString()
         {
-            return $"{base.ToString()}, RateLimitters: {RateLimiters.Count}, RateLimitBehaviour: {RateLimitingBehaviour}, RequestTimeout: {RequestTimeout.ToString("c")}";
+            return $"{base.ToString()}, RateLimiters: {RateLimiters.Count}, RateLimitBehaviour: {RateLimitingBehaviour}, RequestTimeout: {RequestTimeout:c}";
         }
     }
 
@@ -223,7 +223,7 @@ namespace CryptoExchange.Net.Objects
         /// <inheritdoc />
         public override string ToString()
         {
-            return $"{base.ToString()}, AutoReconnect: {AutoReconnect}, ReconnectInterval: {ReconnectInterval}, SocketResponseTimeout: {SocketResponseTimeout.ToString("c")}, SocketSubscriptionsCombineTarget: {SocketSubscriptionsCombineTarget}";
+            return $"{base.ToString()}, AutoReconnect: {AutoReconnect}, ReconnectInterval: {ReconnectInterval}, SocketResponseTimeout: {SocketResponseTimeout:c}, SocketSubscriptionsCombineTarget: {SocketSubscriptionsCombineTarget}";
         }
     }
 }
diff --git a/CryptoExchange.Net/OrderBook/SymbolOrderBook.cs b/CryptoExchange.Net/OrderBook/SymbolOrderBook.cs
index 65aab30..675e8e8 100644
--- a/CryptoExchange.Net/OrderBook/SymbolOrderBook.cs
+++ b/CryptoExchange.Net/OrderBook/SymbolOrderBook.cs
@@ -33,7 +33,11 @@ namespace CryptoExchange.Net.OrderBook
         private OrderBookStatus status;
         private UpdateSubscription? subscription;
         private readonly bool sequencesAreConsecutive;
-        private readonly string id;
+
+        /// <summary>
+        /// Order book implementation id
+        /// </summary>
+        public string Id { get; }
         /// <summary>
         /// The log
         /// </summary>
@@ -54,7 +58,7 @@ namespace CryptoExchange.Net.OrderBook
 
                 var old = status;
                 status = value;
-                log.Write(LogVerbosity.Info, $"{id} order book {Symbol} status changed: {old} => {value}");
+                log.Write(LogVerbosity.Info, $"{Id} order book {Symbol} status changed: {old} => {value}");
                 OnStatusChange?.Invoke(old, status);
             }
         }
@@ -146,12 +150,12 @@ namespace CryptoExchange.Net.OrderBook
         protected SymbolOrderBook(string symbol, OrderBookOptions options)
         {
             if (symbol == null)
-                throw new ArgumentNullException("symbol");
+                throw new ArgumentNullException(nameof(symbol));
 
             if (options == null)
-                throw new ArgumentNullException("options");
+                throw new ArgumentNullException(nameof(options));
 
-            id = options.OrderBookName;
+            Id = options.OrderBookName;
             processBuffer = new List<ProcessBufferEntry>();
             sequencesAreConsecutive = options.SequenceNumbersAreConsecutive;
             Symbol = symbol;
@@ -191,7 +195,7 @@ namespace CryptoExchange.Net.OrderBook
 
         private void Reset()
         {
-            log.Write(LogVerbosity.Warning, $"{id} order book {Symbol} connection lost");
+            log.Write(LogVerbosity.Warning, $"{Id} order book {Symbol} connection lost");
             Status = OrderBookStatus.Connecting;
             processBuffer.Clear();
             bookSet = false;
@@ -211,7 +215,7 @@ namespace CryptoExchange.Net.OrderBook
                 success = resyncResult;
             }
 
-            log.Write(LogVerbosity.Info, $"{id} order book {Symbol} successfully resynchronized");
+            log.Write(LogVerbosity.Info, $"{Id} order book {Symbol} successfully resynchronized");
             Status = OrderBookStatus.Synced;
         }
 
@@ -278,7 +282,7 @@ namespace CryptoExchange.Net.OrderBook
                 bookSet = true;
                 LastOrderBookUpdate = DateTime.UtcNow;
                 OnOrderBookUpdate?.Invoke();
-                log.Write(LogVerbosity.Debug, $"{id} order book {Symbol} data set: {BidCount} bids, {AskCount} asks");
+                log.Write(LogVerbosity.Debug, $"{Id} order book {Symbol} data set: {BidCount} bids, {AskCount} asks");
             }
         }
 
@@ -304,12 +308,12 @@ namespace CryptoExchange.Net.OrderBook
                         Entries = entries
                     };
                     processBuffer.Add(entry);
-                    log.Write(LogVerbosity.Debug, $"{id} order book {Symbol} update before synced; buffering");
+                    log.Write(LogVerbosity.Debug, $"{Id} order book {Symbol} update before synced; buffering");
                 }
                 else if (sequencesAreConsecutive && firstSequenceNumber > LastSequenceNumber + 1)
                 {
                     // Out of sync
-                    log.Write(LogVerbosity.Warning, $"{id} order book {Symbol} out of sync, reconnecting");
+                    log.Write(LogVerbosity.Warning, $"{Id} order book {Symbol} out of sync, reconnecting");
                     subscription!.Reconnect().Wait();
                 }
                 else
@@ -320,7 +324,7 @@ namespace CryptoExchange.Net.OrderBook
                     CheckProcessBuffer();
                     LastOrderBookUpdate = DateTime.UtcNow;
                     OnOrderBookUpdate?.Invoke();
-                    log.Write(LogVerbosity.Debug, $"{id} order book {Symbol} update: {entries.Count} entries processed");
+                    log.Write(LogVerbosity.Debug, $"{Id} order book {Symbol} update: {entries.Count} entries processed");
                 }
             }
         }
diff --git a/CryptoExchange.Net/Requests/Request.cs b/CryptoExchange.Net/Requests/Request.cs
index 4edbd5f..3387cde 100644
--- a/CryptoExchange.Net/Requests/Request.cs
+++ b/CryptoExchange.Net/Requests/Request.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Text;
@@ -11,7 +12,7 @@ namespace CryptoExchange.Net.Requests
     /// <summary>
     /// Request object
     /// </summary>
-    internal class Request : IRequest
+    public class Request : IRequest
     {
         private readonly HttpRequestMessage request;
         private readonly HttpClient httpClient;
@@ -26,10 +27,7 @@ namespace CryptoExchange.Net.Requests
             httpClient = client;
             this.request = request;
         }
-
-        /// <inheritdoc />
-        public HttpRequestHeaders Headers => request.Headers;
-
+        
         /// <inheritdoc />
         public string? Content { get; private set; }
 
@@ -56,6 +54,12 @@ namespace CryptoExchange.Net.Requests
             request.Content = new StringContent(data, Encoding.UTF8, contentType);
         }
 
+        /// <inheritdoc />
+        public void AddHeader(string key, string value)
+        {
+            request.Headers.Add(key, value);
+        }
+
         /// <inheritdoc />
         public void SetContent(byte[] data)
         {
diff --git a/CryptoExchange.Net/Requests/RequestFactory.cs b/CryptoExchange.Net/Requests/RequestFactory.cs
index b91e188..2434ca1 100644
--- a/CryptoExchange.Net/Requests/RequestFactory.cs
+++ b/CryptoExchange.Net/Requests/RequestFactory.cs
@@ -25,8 +25,7 @@ namespace CryptoExchange.Net.Requests
                 }
             };
 
-            httpClient = new HttpClient(handler);
-            httpClient.Timeout = requestTimeout;
+            httpClient = new HttpClient(handler) {Timeout = requestTimeout};
         }
 
         /// <inheritdoc />
diff --git a/CryptoExchange.Net/RestClient.cs b/CryptoExchange.Net/RestClient.cs
index a635a73..11aa854 100644
--- a/CryptoExchange.Net/RestClient.cs
+++ b/CryptoExchange.Net/RestClient.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using System.Net.Http;
@@ -46,11 +47,11 @@ namespace CryptoExchange.Net
         /// <summary>
         /// Timeout for requests
         /// </summary>
-        protected TimeSpan RequestTimeout { get; private set; }
+        protected TimeSpan RequestTimeout { get; }
         /// <summary>
         /// Rate limiting behaviour
         /// </summary>
-        public RateLimitingBehaviour RateLimitBehaviour { get; private set; }
+        public RateLimitingBehaviour RateLimitBehaviour { get; }
         /// <summary>
         /// List of ratelimitters
         /// </summary>
@@ -68,7 +69,7 @@ namespace CryptoExchange.Net
         protected RestClient(RestClientOptions exchangeOptions, AuthenticationProvider? authenticationProvider): base(exchangeOptions, authenticationProvider)
         {
             if (exchangeOptions == null)
-                throw new ArgumentNullException("Options");
+                throw new ArgumentNullException(nameof(exchangeOptions));
 
             RequestTimeout = exchangeOptions.RequestTimeout;
             RequestFactory.Configure(exchangeOptions.RequestTimeout, exchangeOptions.Proxy);
@@ -86,7 +87,7 @@ namespace CryptoExchange.Net
         public void AddRateLimiter(IRateLimiter limiter)
         {
             if (limiter == null)
-                throw new ArgumentNullException("limiter");
+                throw new ArgumentNullException(nameof(limiter));
 
             var rateLimiters = RateLimiters.ToList();
             rateLimiters.Add(limiter);
@@ -105,17 +106,19 @@ namespace CryptoExchange.Net
         /// Ping to see if the server is reachable
         /// </summary>
         /// <returns>The roundtrip time of the ping request</returns>
-        public virtual CallResult<long> Ping() => PingAsync().Result;
+        public virtual CallResult<long> Ping(CancellationToken ct = default) => PingAsync(ct).Result;
 
         /// <summary>
         /// Ping to see if the server is reachable
         /// </summary>
         /// <returns>The roundtrip time of the ping request</returns>
-        public virtual async Task<CallResult<long>> PingAsync()
+        public virtual async Task<CallResult<long>> PingAsync(CancellationToken ct = default)
         {
             var ping = new Ping();
             var uri = new Uri(BaseAddress);
             PingReply reply;
+
+            var ctRegistration = ct.Register(() => ping.SendAsyncCancel());
             try
             {
                 reply = await ping.SendPingAsync(uri.Host).ConfigureAwait(false);
@@ -131,9 +134,13 @@ namespace CryptoExchange.Net
             }
             finally
             {
+                ctRegistration.Dispose();
                 ping.Dispose();
             }
 
+            if(ct.IsCancellationRequested)
+                return new CallResult<long>(0, new CancellationRequestedError());
+
             return reply.Status == IPStatus.Success ? new CallResult<long>(reply.RoundtripTime, null) : new CallResult<long>(0, new CantConnectError { Message = "Ping failed: " + reply.Status });
         }
 
@@ -148,6 +155,7 @@ namespace CryptoExchange.Net
         /// <param name="signed">Whether or not the request should be authenticated</param>
         /// <param name="checkResult">Whether or not the resulting object should be checked for missing properties in the mapping (only outputs if log verbosity is Debug)</param>
         /// <returns></returns>
+        [return: NotNull]
         protected virtual async Task<WebCallResult<T>> SendRequest<T>(Uri uri, HttpMethod method, CancellationToken cancellationToken,
             Dictionary<string, object>? parameters = null, bool signed = false, bool checkResult = true) where T : class
         {
@@ -198,13 +206,17 @@ namespace CryptoExchange.Net
                 if (response.IsSuccessStatusCode)
                 {
                     var desResult = await Deserialize<T>(responseStream).ConfigureAwait(false);
+                    responseStream.Close();
                     response.Close();
+
+
                     return new WebCallResult<T>(statusCode, headers, desResult.Data, desResult.Error);
                 }
                 else
                 {
                     using var reader = new StreamReader(responseStream);
                     var data = await reader.ReadToEndAsync().ConfigureAwait(false);
+                    responseStream.Close();
                     response.Close();
                     var parseResult = ValidateJson(data);
                     return new WebCallResult<T>(statusCode, headers, default, parseResult.Success ? ParseErrorResponse(parseResult.Data) :new ServerError(data));
@@ -261,7 +273,7 @@ namespace CryptoExchange.Net
                 headers = authProvider.AddAuthenticationToHeaders(uriString, method, parameters!, signed);
 
             foreach (var header in headers)
-                request.Headers.Add(header.Key, header.Value);
+                request.AddHeader(header.Key, header.Value);
 
             if ((method == HttpMethod.Post || method == HttpMethod.Put) && postParametersPosition != PostParameters.InUri)
             {
@@ -286,7 +298,6 @@ namespace CryptoExchange.Net
             {
                 var stringData = JsonConvert.SerializeObject(parameters.OrderBy(p => p.Key).ToDictionary(p => p.Key, p => p.Value));
                 request.SetContent(stringData, contentType);
-
             }
             else if(requestBodyFormat == RequestBodyFormat.FormData)
             {
diff --git a/CryptoExchange.Net/SocketClient.cs b/CryptoExchange.Net/SocketClient.cs
index ef99cfb..b416553 100644
--- a/CryptoExchange.Net/SocketClient.cs
+++ b/CryptoExchange.Net/SocketClient.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -33,13 +34,13 @@ namespace CryptoExchange.Net
         protected internal readonly SemaphoreSlim semaphoreSlim = new SemaphoreSlim(1);
 
         /// <inheritdoc cref="SocketClientOptions.ReconnectInterval"/>
-        public TimeSpan ReconnectInterval { get; private set; }
+        public TimeSpan ReconnectInterval { get; }
         /// <inheritdoc cref="SocketClientOptions.AutoReconnect"/>
-        public bool AutoReconnect { get; private set; }
+        public bool AutoReconnect { get; }
         /// <inheritdoc cref="SocketClientOptions.SocketResponseTimeout"/>
-        public TimeSpan ResponseTimeout { get; private set; }
+        public TimeSpan ResponseTimeout { get; }
         /// <inheritdoc cref="SocketClientOptions.SocketNoDataTimeout"/>
-        public TimeSpan SocketNoDataTimeout { get; private set; }
+        public TimeSpan SocketNoDataTimeout { get; }
         /// <summary>
         /// The max amount of concurrent socket connections
         /// </summary>
@@ -87,7 +88,7 @@ namespace CryptoExchange.Net
         protected SocketClient(SocketClientOptions exchangeOptions, AuthenticationProvider? authenticationProvider): base(exchangeOptions, authenticationProvider)
         {
             if (exchangeOptions == null)
-                throw new ArgumentNullException("Options");
+                throw new ArgumentNullException(nameof(exchangeOptions));
 
             AutoReconnect = exchangeOptions.AutoReconnect;
             ReconnectInterval = exchangeOptions.ReconnectInterval;
@@ -101,7 +102,7 @@ namespace CryptoExchange.Net
         /// </summary>
         /// <param name="byteHandler">Handler for byte data</param>
         /// <param name="stringHandler">Handler for string data</param>
-        protected void SetDataInterpreter(Func<byte[], string> byteHandler, Func<string, string> stringHandler)
+        protected void SetDataInterpreter(Func<byte[], string>? byteHandler, Func<string, string>? stringHandler)
         {
             dataInterpreterBytes = byteHandler;
             dataInterpreterString = stringHandler;
@@ -116,7 +117,7 @@ namespace CryptoExchange.Net
         /// <param name="authenticated">If the subscription should be authenticated</param>
         /// <param name="dataHandler">The handler of update data</param>
         /// <returns></returns>
-        protected virtual Task<CallResult<UpdateSubscription>> Subscribe<T>(object request, string identifier, bool authenticated, Action<T> dataHandler)
+        protected virtual Task<CallResult<UpdateSubscription>> Subscribe<T>(object? request, string? identifier, bool authenticated, Action<T> dataHandler)
         {
             return Subscribe(BaseAddress, request, identifier, authenticated, dataHandler);
         }
@@ -171,8 +172,10 @@ namespace CryptoExchange.Net
                 }
             }
             else
+            {
                 handler.Confirmed = true;
-
+            }
+            
             socket.ShouldReconnect = true;
             return new CallResult<UpdateSubscription>(new UpdateSubscription(socket, handler), null);
         }
@@ -187,7 +190,7 @@ namespace CryptoExchange.Net
         protected internal virtual async Task<CallResult<bool>> SubscribeAndWait(SocketConnection socket, object request, SocketSubscription subscription)
         {
             CallResult<object>? callResult = null;
-            await socket.SendAndWait(request, ResponseTimeout, data => HandleSubscriptionResponse(socket, subscription, request, data, out var callResult)).ConfigureAwait(false);
+            await socket.SendAndWait(request, ResponseTimeout, data => HandleSubscriptionResponse(socket, subscription, request, data, out callResult)).ConfigureAwait(false);
 
             if (callResult?.Success == true)
                 subscription.Confirmed = true;
@@ -312,7 +315,7 @@ namespace CryptoExchange.Net
         /// <param name="data">The message</param>
         /// <param name="callResult">The interpretation (null if message wasn't a response to the request)</param>
         /// <returns>True if the message was a response to the query</returns>
-        protected internal abstract bool HandleQueryResponse<T>(SocketConnection s, object request, JToken data, out CallResult<T> callResult);
+        protected internal abstract bool HandleQueryResponse<T>(SocketConnection s, object request, JToken data, [NotNullWhen(true)]out CallResult<T>? callResult);
         /// <summary>
         /// Needs to check if a received message was an answer to a subscription request (preferable by id) and set the callResult out to whatever the response is
         /// </summary>
@@ -322,7 +325,7 @@ namespace CryptoExchange.Net
         /// <param name="message">The message</param>
         /// <param name="callResult">The interpretation (null if message wasn't a response to the request)</param>
         /// <returns>True if the message was a response to the subscription request</returns>
-        protected internal abstract bool HandleSubscriptionResponse(SocketConnection s, SocketSubscription subscription, object request, JToken message, out CallResult<object> callResult);
+        protected internal abstract bool HandleSubscriptionResponse(SocketConnection s, SocketSubscription subscription, object request, JToken message, out CallResult<object>? callResult);
         /// <summary>
         /// Needs to check if a received message matches a handler. Typically if an update message matches the request
         /// </summary>
@@ -391,7 +394,11 @@ namespace CryptoExchange.Net
                 dataHandler(desResult.Data);
             }
 
-            return connection.AddHandler(request ?? identifier!, userSubscription, InternalHandler);
+            var handler = request == null
+                ? SocketSubscription.CreateForIdentifier(identifier!, userSubscription, InternalHandler)
+                : SocketSubscription.CreateForRequest(request, userSubscription, InternalHandler);
+            connection.AddHandler(handler);
+            return handler;
         }
 
         /// <summary>
@@ -399,11 +406,12 @@ namespace CryptoExchange.Net
         /// </summary>
         /// <param name="identifier">The name of the request handler. Needs to be unique</param>
         /// <param name="action">The action to execute when receiving a message for this handler (checked by <see cref="MessageMatchesHandler(Newtonsoft.Json.Linq.JToken,string)"/>)</param>
-        protected virtual void AddGenericHandler(string identifier, Action<SocketConnection, JToken> action)
+        protected void AddGenericHandler(string identifier, Action<SocketConnection, JToken> action)
         {
             genericHandlers.Add(identifier, action);
+            var handler = SocketSubscription.CreateForIdentifier(identifier, false, action);
             foreach (var connection in sockets.Values)
-                connection.AddHandler(identifier, false, action);
+                connection.AddHandler(handler);
         }
 
         /// <summary>
@@ -429,7 +437,11 @@ namespace CryptoExchange.Net
             var socket = CreateSocket(address);
             var socketWrapper = new SocketConnection(this, socket);
             foreach (var kvp in genericHandlers)
-                socketWrapper.AddHandler(kvp.Key, false, kvp.Value);
+            {
+                var handler = SocketSubscription.CreateForIdentifier(kvp.Key, false, kvp.Value);
+                socketWrapper.AddHandler(handler);
+            }
+
             return socketWrapper;
         }
 
@@ -468,7 +480,7 @@ namespace CryptoExchange.Net
             socket.DataInterpreterString = dataInterpreterString;
             socket.OnError += e =>
             {
-                log.Write(LogVerbosity.Info, $"Socket {socket.Id} error: " + e.ToString());
+                log.Write(LogVerbosity.Info, $"Socket {socket.Id} error: " + e);
             };
             return socket;
         }
@@ -481,7 +493,7 @@ namespace CryptoExchange.Net
         public virtual void SendPeriodic(TimeSpan interval, Func<SocketConnection, object> objGetter)
         {
             if (objGetter == null)
-                throw new ArgumentNullException("objGetter");
+                throw new ArgumentNullException(nameof(objGetter));
 
             periodicEvent = new AutoResetEvent(false);
             periodicTask = Task.Run(async () =>
@@ -526,7 +538,7 @@ namespace CryptoExchange.Net
         public virtual async Task Unsubscribe(UpdateSubscription subscription)
         {
             if (subscription == null)
-                throw new ArgumentNullException("subscription");
+                throw new ArgumentNullException(nameof(subscription));
 
             log.Write(LogVerbosity.Info, "Closing subscription");
             await subscription.Close().ConfigureAwait(false);
@@ -538,7 +550,7 @@ namespace CryptoExchange.Net
         /// <returns></returns>
         public virtual async Task UnsubscribeAll()
         {
-            log.Write(LogVerbosity.Debug, $"Closing all {sockets.Sum(s => s.Value.handlers.Count(h => h.UserSubscription))} subscriptions");
+            log.Write(LogVerbosity.Debug, $"Closing all {sockets.Sum(s => s.Value.HandlerCount)} subscriptions");
 
             await Task.Run(() =>
             {
diff --git a/CryptoExchange.Net/Sockets/BaseSocket.cs b/CryptoExchange.Net/Sockets/BaseSocket.cs
index e2a9aa5..a69be1f 100644
--- a/CryptoExchange.Net/Sockets/BaseSocket.cs
+++ b/CryptoExchange.Net/Sockets/BaseSocket.cs
@@ -16,45 +16,111 @@ namespace CryptoExchange.Net.Sockets
     /// <summary>
     /// Socket implementation
     /// </summary>
-    internal class BaseSocket: IWebsocket
+    public class BaseSocket: IWebsocket
     {
         internal static int lastStreamId;
         private static readonly object streamIdLock = new object();
 
+        /// <summary>
+        /// Socket
+        /// </summary>
         protected WebSocket? socket;
+        /// <summary>
+        /// Log
+        /// </summary>
         protected Log log;
-        protected object socketLock = new object();
+        private readonly object socketLock = new object();
 
+        /// <summary>
+        /// Error handlers
+        /// </summary>
         protected readonly List<Action<Exception>> errorHandlers = new List<Action<Exception>>();
+        /// <summary>
+        /// Open handlers
+        /// </summary>
         protected readonly List<Action> openHandlers = new List<Action>();
+        /// <summary>
+        /// Close handlers
+        /// </summary>
         protected readonly List<Action> closeHandlers = new List<Action>();
+        /// <summary>
+        /// Message handlers
+        /// </summary>
         protected readonly List<Action<string>> messageHandlers = new List<Action<string>>();
 
-        protected IDictionary<string, string> cookies;
-        protected IDictionary<string, string> headers;
-        protected HttpConnectProxy? proxy;
+        private readonly IDictionary<string, string> cookies;
+        private readonly IDictionary<string, string> headers;
+        private HttpConnectProxy? proxy;
 
+        /// <summary>
+        /// Id
+        /// </summary>
         public int Id { get; }
+        /// <summary>
+        /// If is reconnecting
+        /// </summary>
         public bool Reconnecting { get; set; }
+        /// <summary>
+        /// Origin
+        /// </summary>
         public string? Origin { get; set; }
 
+        /// <summary>
+        /// Url
+        /// </summary>
         public string Url { get; }
-        public bool IsClosed => socket?.State == null ? true: socket.State == WebSocketState.Closed;
+        /// <summary>
+        /// Is closed
+        /// </summary>
+        public bool IsClosed => socket?.State == null || socket.State == WebSocketState.Closed;
+        /// <summary>
+        /// Is open
+        /// </summary>
         public bool IsOpen => socket?.State == WebSocketState.Open;
+        /// <summary>
+        /// Protocols
+        /// </summary>
         public SslProtocols SSLProtocols { get; set; } = SslProtocols.Tls12 | SslProtocols.Tls11 | SslProtocols.Tls;
+        /// <summary>
+        /// Interpreter for bytes
+        /// </summary>
         public Func<byte[], string>? DataInterpreterBytes { get; set; }
+        /// <summary>
+        /// Interpreter for strings
+        /// </summary>
         public Func<string, string>? DataInterpreterString { get; set; }
 
+        /// <summary>
+        /// Last action time
+        /// </summary>
         public DateTime LastActionTime { get; private set; }
+        /// <summary>
+        /// Timeout
+        /// </summary>
         public TimeSpan Timeout { get; set; }
         private Task? timeoutTask;
 
+        /// <summary>
+        /// Socket state
+        /// </summary>
         public WebSocketState SocketState => socket?.State ?? WebSocketState.None;
 
+        /// <summary>
+        /// ctor
+        /// </summary>
+        /// <param name="log"></param>
+        /// <param name="url"></param>
         public BaseSocket(Log log, string url):this(log, url, new Dictionary<string, string>(), new Dictionary<string, string>())
         {
         }
 
+        /// <summary>
+        /// ctor
+        /// </summary>
+        /// <param name="log"></param>
+        /// <param name="url"></param>
+        /// <param name="cookies"></param>
+        /// <param name="headers"></param>
         public BaseSocket(Log log, string url, IDictionary<string, string> cookies, IDictionary<string, string> headers)
         {
             Id = NextStreamId();
@@ -94,27 +160,43 @@ namespace CryptoExchange.Net.Sockets
             }
         }
 
+        /// <summary>
+        /// On close
+        /// </summary>
         public event Action OnClose
         {
             add => closeHandlers.Add(value);
             remove => closeHandlers.Remove(value);
         }
+        /// <summary>
+        /// On message
+        /// </summary>
         public event Action<string> OnMessage
         {
             add => messageHandlers.Add(value);
             remove => messageHandlers.Remove(value);
         }
+        /// <summary>
+        /// On error
+        /// </summary>
         public event Action<Exception> OnError
         {
             add => errorHandlers.Add(value);
             remove => errorHandlers.Remove(value);
         }
+        /// <summary>
+        /// On open
+        /// </summary>
         public event Action OnOpen
         {
             add => openHandlers.Add(value);
             remove => openHandlers.Remove(value);
         }
 
+        /// <summary>
+        /// Handle
+        /// </summary>
+        /// <param name="handlers"></param>
         protected void Handle(List<Action> handlers)
         {
             LastActionTime = DateTime.UtcNow;
@@ -122,6 +204,12 @@ namespace CryptoExchange.Net.Sockets
                 handle?.Invoke();
         }
 
+        /// <summary>
+        /// Handle
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="handlers"></param>
+        /// <param name="data"></param>
         protected void Handle<T>(List<Action<T>> handlers, T data)
         {
             LastActionTime = DateTime.UtcNow;
@@ -129,6 +217,10 @@ namespace CryptoExchange.Net.Sockets
                 handle?.Invoke(data);
         }
 
+        /// <summary>
+        /// Checks if timed out
+        /// </summary>
+        /// <returns></returns>
         protected async Task CheckTimeout()
         {
             while (true)
@@ -150,6 +242,10 @@ namespace CryptoExchange.Net.Sockets
             }
         }
 
+        /// <summary>
+        /// Close socket
+        /// </summary>
+        /// <returns></returns>
         public virtual async Task Close()
         {
             await Task.Run(() =>
@@ -184,6 +280,9 @@ namespace CryptoExchange.Net.Sockets
             }).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Reset socket
+        /// </summary>
         public virtual void Reset()
         {
             lock (socketLock)
@@ -194,11 +293,19 @@ namespace CryptoExchange.Net.Sockets
             }
         }
 
+        /// <summary>
+        /// Send data
+        /// </summary>
+        /// <param name="data"></param>
         public virtual void Send(string data)
         {
             socket?.Send(data);
         }
 
+        /// <summary>
+        /// Connect socket
+        /// </summary>
+        /// <returns></returns>
         public virtual Task<bool> Connect()
         {
             if (socket == null)
@@ -259,7 +366,9 @@ namespace CryptoExchange.Net.Sockets
                             timeoutTask = Task.Run(CheckTimeout);
                     }
                     else
+                    {
                         log?.Write(LogVerbosity.Debug, $"Socket {Id} connection failed, state: " + socket.State);
+                    }
                 }
 
                 if (socket.State == WebSocketState.Connecting)
@@ -269,6 +378,11 @@ namespace CryptoExchange.Net.Sockets
             });
         }
         
+        /// <summary>
+        /// Set a proxy
+        /// </summary>
+        /// <param name="host"></param>
+        /// <param name="port"></param>
         public virtual void SetProxy(string host, int port)
         {
             proxy = IPAddress.TryParse(host, out var address)
@@ -276,6 +390,9 @@ namespace CryptoExchange.Net.Sockets
                 : new HttpConnectProxy(new DnsEndPoint(host, port));
         }
 
+        /// <summary>
+        /// Dispose
+        /// </summary>
         public void Dispose()
         {
             lock (socketLock)
diff --git a/CryptoExchange.Net/Sockets/SocketConnection.cs b/CryptoExchange.Net/Sockets/SocketConnection.cs
index 4c8443b..b7e8b9a 100644
--- a/CryptoExchange.Net/Sockets/SocketConnection.cs
+++ b/CryptoExchange.Net/Sockets/SocketConnection.cs
@@ -65,7 +65,7 @@ namespace CryptoExchange.Net.Sockets
         /// </summary>
         public bool PausedActivity { get; set; }
 
-        internal readonly List<SocketSubscription> handlers;
+        private readonly List<SocketSubscription> handlers;
         private readonly object handlersLock = new object();
 
         private bool lostTriggered;
@@ -109,38 +109,7 @@ namespace CryptoExchange.Net.Sockets
                 Connected = true;
             };
         }
-
-        /// <summary>
-        /// Add a handler
-        /// </summary>
-        /// <param name="request">The request object</param>
-        /// <param name="userSubscription">If it is a user subscription or a generic handler</param>
-        /// <param name="dataHandler">The data handler</param>
-        /// <returns></returns>
-        public SocketSubscription AddHandler(object request, bool userSubscription, Action<SocketConnection, JToken> dataHandler)
-        {
-            var handler = new SocketSubscription(request, userSubscription, dataHandler);
-            lock (handlersLock)
-                handlers.Add(handler);
-            return handler;
-        }
-
-        /// <summary>
-        /// Add a handler
-        /// </summary>
-        /// <param name="identifier">The identifier of the handler</param>
-        /// <param name="userSubscription">If it is a user subscription or a generic handler</param>
-        /// <param name="dataHandler">The data handler</param>
-        /// <returns></returns>
-        /// <returns></returns>
-        public SocketSubscription AddHandler(string identifier, bool userSubscription, Action<SocketConnection, JToken> dataHandler)
-        {
-            var handler = new SocketSubscription(identifier, userSubscription, dataHandler);
-            lock (handlersLock)
-                handlers.Add(handler);
-            return handler;
-        }
-
+        
         private void ProcessMessage(string data)
         {
             log.Write(LogVerbosity.Debug, $"Socket {Socket.Id} received data: " + data);
@@ -167,6 +136,16 @@ namespace CryptoExchange.Net.Sockets
             }
         }
 
+        /// <summary>
+        /// Add handler
+        /// </summary>
+        /// <param name="handler"></param>
+        public void AddHandler(SocketSubscription handler)
+        {
+            lock(handlersLock)
+                handlers.Add(handler);
+        }
+
         private bool HandleData(JToken tokenData)
         {
             SocketSubscription? currentSubscription = null;
diff --git a/CryptoExchange.Net/Sockets/SocketSubscription.cs b/CryptoExchange.Net/Sockets/SocketSubscription.cs
index 0f1df22..492ab9d 100644
--- a/CryptoExchange.Net/Sockets/SocketSubscription.cs
+++ b/CryptoExchange.Net/Sockets/SocketSubscription.cs
@@ -36,30 +36,38 @@ namespace CryptoExchange.Net.Sockets
         /// </summary>
         public bool Confirmed { get; set; }
 
-        /// <summary>
-        /// ctor
-        /// </summary>
-        /// <param name="request"></param>
-        /// <param name="userSubscription"></param>
-        /// <param name="dataHandler"></param>
-        public SocketSubscription(object request, bool userSubscription, Action<SocketConnection, JToken> dataHandler)
+        private SocketSubscription(object? request, string? identifier, bool userSubscription, Action<SocketConnection, JToken> dataHandler)
         {
             UserSubscription = userSubscription;
             MessageHandler = dataHandler;
             Request = request;
+            Identifier = identifier;
         }
 
         /// <summary>
-        /// ctor
+        /// Create SocketSubscription for a request
+        /// </summary>
+        /// <param name="request"></param>
+        /// <param name="userSubscription"></param>
+        /// <param name="dataHandler"></param>
+        /// <returns></returns>
+        public static SocketSubscription CreateForRequest(object request, bool userSubscription,
+            Action<SocketConnection, JToken> dataHandler)
+        {
+            return new SocketSubscription(request, null, userSubscription, dataHandler);
+        }
+
+        /// <summary>
+        /// Create SocketSubscription for an identifier
         /// </summary>
         /// <param name="identifier"></param>
         /// <param name="userSubscription"></param>
         /// <param name="dataHandler"></param>
-        public SocketSubscription(string identifier, bool userSubscription, Action<SocketConnection, JToken> dataHandler)
+        /// <returns></returns>
+        public static SocketSubscription CreateForIdentifier(string identifier, bool userSubscription,
+            Action<SocketConnection, JToken> dataHandler)
         {
-            UserSubscription = userSubscription;
-            MessageHandler = dataHandler;
-            Identifier = identifier;
+            return new SocketSubscription(null, identifier, userSubscription, dataHandler);
         }
 
         /// <summary>