diff --git a/src/MusicStore.Spa/Startup.cs b/src/MusicStore.Spa/Startup.cs
index 9cce579e94..1faafbbfd7 100644
--- a/src/MusicStore.Spa/Startup.cs
+++ b/src/MusicStore.Spa/Startup.cs
@@ -16,7 +16,7 @@ namespace MusicStore.Spa
 {
     public class Startup
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             var configuration = new Configuration()
                 .AddJsonFile("Config.json")
diff --git a/src/MusicStore/Mocks/StartupSocialTesting.cs b/src/MusicStore/Mocks/StartupSocialTesting.cs
index dc285b5299..20974508ad 100644
--- a/src/MusicStore/Mocks/StartupSocialTesting.cs
+++ b/src/MusicStore/Mocks/StartupSocialTesting.cs
@@ -24,7 +24,7 @@ namespace MusicStore
 {
     public class StartupSocialTesting
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             Console.WriteLine("Social Testing mode...");
             //Below code demonstrates usage of multiple configuration sources. For instance a setting say 'setting1' is found in both the registered sources, 
diff --git a/src/MusicStore/Startup.cs b/src/MusicStore/Startup.cs
index 7ceb59052f..e12ca0b5ca 100644
--- a/src/MusicStore/Startup.cs
+++ b/src/MusicStore/Startup.cs
@@ -20,7 +20,7 @@ namespace MusicStore
 {
     public class Startup
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             //Below code demonstrates usage of multiple configuration sources. For instance a setting say 'setting1' is found in both the registered sources, 
             //then the later source will win. By this way a Local config can be overridden by a different setting while deployed remotely.
diff --git a/src/MusicStore/StartupNtlmAuthentication.cs b/src/MusicStore/StartupNtlmAuthentication.cs
index c489553b7f..db269c05b4 100644
--- a/src/MusicStore/StartupNtlmAuthentication.cs
+++ b/src/MusicStore/StartupNtlmAuthentication.cs
@@ -30,7 +30,7 @@ namespace MusicStore
     /// </summary>
     public class StartupNtlmAuthentication
     {
-        public void Configure(IBuilder app)
+        public void Configure(IApplicationBuilder app)
         {
             //Set up NTLM authentication for WebListener like below. 
             //For IIS and IISExpress: Use inetmgr to setup NTLM authentication on the application vDir or modify the applicationHost.config to enable NTLM.