diff --git a/samples/SampleApp/project.json b/samples/SampleApp/project.json
index 6cdf28bc48..f116683326 100644
--- a/samples/SampleApp/project.json
+++ b/samples/SampleApp/project.json
@@ -1,4 +1,4 @@
-{
+{
     "version": "1.0.0-*",
     "dependencies": {
         "Kestrel": "1.0.0-*",
@@ -7,7 +7,7 @@
     },
     "frameworks": {
         "net45": { },
-        "k10": {
+        "aspnetcore50": {
             "dependencies": {
                 "System.Console": "4.0.0.0"
             }
diff --git a/src/Kestrel/project.json b/src/Kestrel/project.json
index 1f8ca15042..ea2f0f22df 100644
--- a/src/Kestrel/project.json
+++ b/src/Kestrel/project.json
@@ -1,4 +1,4 @@
-{
+{
     "version": "1.0.0-*",
     "dependencies": {
         "Microsoft.AspNet.Hosting": "1.0.0-*",
@@ -8,7 +8,7 @@
         "net45": {
             "dependencies": { }
         },
-        "k10": {
+        "aspnetcore50": {
             "dependencies": {
                 "System.Runtime": "4.0.20.0"
             }
diff --git a/src/Microsoft.AspNet.Server.Kestrel/Networking/PlatformApis.cs b/src/Microsoft.AspNet.Server.Kestrel/Networking/PlatformApis.cs
index 7803250f87..d7907e4d88 100644
--- a/src/Microsoft.AspNet.Server.Kestrel/Networking/PlatformApis.cs
+++ b/src/Microsoft.AspNet.Server.Kestrel/Networking/PlatformApis.cs
@@ -12,7 +12,7 @@ namespace Microsoft.AspNet.Server.Kestrel.Networking
     {
         public static bool IsWindows() 
         {
-#if K10
+#if ASPNETCORE50
             return true;
 #else
             var p = (int)Environment.OSVersion.Platform;
diff --git a/src/Microsoft.AspNet.Server.Kestrel/project.json b/src/Microsoft.AspNet.Server.Kestrel/project.json
index cdf77c22f4..44c423ad5b 100644
--- a/src/Microsoft.AspNet.Server.Kestrel/project.json
+++ b/src/Microsoft.AspNet.Server.Kestrel/project.json
@@ -10,7 +10,7 @@
                 "allowUnsafe": true
             }
         },
-        "k10": {
+        "aspnetcore50": {
             "compilationOptions": {
                 "define": [ "TRACE", "K10" ],
                 "allowUnsafe": true
diff --git a/test/Microsoft.AspNet.Server.KestrelTests/project.json b/test/Microsoft.AspNet.Server.KestrelTests/project.json
index 17f1a499c1..81324784a0 100644
--- a/test/Microsoft.AspNet.Server.KestrelTests/project.json
+++ b/test/Microsoft.AspNet.Server.KestrelTests/project.json
@@ -8,7 +8,7 @@
         "net45": {
             "compilationOptions": { "define": [ "TRACE" ] }
         },
-        "k10": {
+        "aspnetcore50": {
             "compilationOptions": { "define": [ "TRACE" ] },
             "dependencies": {
                 "System.Net.Sockets": "4.0.0.0",