diff --git a/src/Microsoft.AspNetCore.Http.Abstractions/project.json b/src/Microsoft.AspNetCore.Http.Abstractions/project.json
index 20578bac5c..23f72dfaa3 100644
--- a/src/Microsoft.AspNetCore.Http.Abstractions/project.json
+++ b/src/Microsoft.AspNetCore.Http.Abstractions/project.json
@@ -8,7 +8,9 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -26,7 +28,7 @@
         "System.Runtime": ""
       }
     },
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
         "System.ComponentModel": "4.0.1-*",
         "System.Globalization.Extensions": "4.0.1-*",
@@ -35,7 +37,10 @@
         "System.Reflection.TypeExtensions": "4.1.0-*",
         "System.Runtime.InteropServices": "4.1.0-*",
         "System.Security.Cryptography.X509Certificates": "4.0.0-*"
-      }
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Http.Extensions/project.json b/src/Microsoft.AspNetCore.Http.Extensions/project.json
index 7f9b1ab34a..81c223a0ff 100644
--- a/src/Microsoft.AspNetCore.Http.Extensions/project.json
+++ b/src/Microsoft.AspNetCore.Http.Extensions/project.json
@@ -8,7 +8,9 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -19,10 +21,13 @@
   },
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
         "System.IO.FileSystem": "4.0.1-*"
-      }
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Http.Features/project.json b/src/Microsoft.AspNetCore.Http.Features/project.json
index 93ba9e9d4f..da11fe30e5 100644
--- a/src/Microsoft.AspNetCore.Http.Features/project.json
+++ b/src/Microsoft.AspNetCore.Http.Features/project.json
@@ -8,7 +8,9 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -16,7 +18,7 @@
   },
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
         "System.Collections": "4.0.11-*",
         "System.Linq": "4.1.0-*",
@@ -26,7 +28,10 @@
         "System.Security.Claims": "4.0.1-*",
         "System.Security.Cryptography.X509Certificates": "4.0.0-*",
         "System.Security.Principal": "4.0.1-*"
-      }
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Http/FormCollection.cs b/src/Microsoft.AspNetCore.Http/FormCollection.cs
index 33c36d558d..6e44c39aad 100644
--- a/src/Microsoft.AspNetCore.Http/FormCollection.cs
+++ b/src/Microsoft.AspNetCore.Http/FormCollection.cs
@@ -14,7 +14,7 @@ namespace Microsoft.AspNetCore.Http.Internal
     public class FormCollection : IFormCollection
     {
         public static readonly FormCollection Empty = new FormCollection();
-#if DOTNET5_4
+#if NETSTANDARD1_3
         private static readonly string[] EmptyKeys = Array.Empty<string>();
         private static readonly StringValues[] EmptyValues = Array.Empty<StringValues>();
 #else
diff --git a/src/Microsoft.AspNetCore.Http/HeaderDictionary.cs b/src/Microsoft.AspNetCore.Http/HeaderDictionary.cs
index a885ccad8c..304457459e 100644
--- a/src/Microsoft.AspNetCore.Http/HeaderDictionary.cs
+++ b/src/Microsoft.AspNetCore.Http/HeaderDictionary.cs
@@ -13,7 +13,7 @@ namespace Microsoft.AspNetCore.Http.Internal
     /// </summary>
     public class HeaderDictionary : IHeaderDictionary
     {
-#if DOTNET5_4
+#if NETSTANDARD1_3
         private static readonly string[] EmptyKeys = Array.Empty<string>();
         private static readonly StringValues[] EmptyValues = Array.Empty<StringValues>();
 #else
diff --git a/src/Microsoft.AspNetCore.Http/HttpContextAccessor.cs b/src/Microsoft.AspNetCore.Http/HttpContextAccessor.cs
index e009bf1cb1..be6bb471a6 100644
--- a/src/Microsoft.AspNetCore.Http/HttpContextAccessor.cs
+++ b/src/Microsoft.AspNetCore.Http/HttpContextAccessor.cs
@@ -5,7 +5,7 @@ using System;
 #if NET451
 using System.Runtime.Remoting.Messaging;
 using System.Runtime.Remoting;
-#elif DOTNET5_4
+#elif NETSTANDARD1_3
 using System.Threading;
 #endif
 
@@ -29,7 +29,7 @@ namespace Microsoft.AspNetCore.Http.Internal
             }
         }
 
-#elif DOTNET5_4
+#elif NETSTANDARD1_3
         private AsyncLocal<HttpContext> _httpContextCurrent = new AsyncLocal<HttpContext>();
         public HttpContext HttpContext
         {
diff --git a/src/Microsoft.AspNetCore.Http/QueryCollection.cs b/src/Microsoft.AspNetCore.Http/QueryCollection.cs
index fb0a260ceb..1809635d8b 100644
--- a/src/Microsoft.AspNetCore.Http/QueryCollection.cs
+++ b/src/Microsoft.AspNetCore.Http/QueryCollection.cs
@@ -14,7 +14,7 @@ namespace Microsoft.AspNetCore.Http.Internal
     public class QueryCollection : IQueryCollection
     {
         public static readonly QueryCollection Empty = new QueryCollection();
-#if DOTNET5_4
+#if NETSTANDARD1_3
         private static readonly string[] EmptyKeys = Array.Empty<string>();
         private static readonly StringValues[] EmptyValues = Array.Empty<StringValues>();
 #else
diff --git a/src/Microsoft.AspNetCore.Http/RequestCookieCollection.cs b/src/Microsoft.AspNetCore.Http/RequestCookieCollection.cs
index b8e4f2d7b1..68a2f35968 100644
--- a/src/Microsoft.AspNetCore.Http/RequestCookieCollection.cs
+++ b/src/Microsoft.AspNetCore.Http/RequestCookieCollection.cs
@@ -11,7 +11,7 @@ namespace Microsoft.AspNetCore.Http.Internal
     public class RequestCookieCollection : IRequestCookieCollection
     {
         public static readonly RequestCookieCollection Empty = new RequestCookieCollection();
-#if DOTNET5_4
+#if NETSTANDARD1_3
         private static readonly string[] EmptyKeys = Array.Empty<string>();
 #else
         private static readonly string[] EmptyKeys = new string[0];
diff --git a/src/Microsoft.AspNetCore.Http/project.json b/src/Microsoft.AspNetCore.Http/project.json
index c2bc71063e..8e1578e21c 100644
--- a/src/Microsoft.AspNetCore.Http/project.json
+++ b/src/Microsoft.AspNetCore.Http/project.json
@@ -9,7 +9,9 @@
     "warningsAsErrors": true,
     "allowUnsafe": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -19,10 +21,13 @@
   },
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
-        "System.Threading":  "4.0.11-*"
-      }
+        "System.Threading": "4.0.11-*"
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.Owin/project.json b/src/Microsoft.AspNetCore.Owin/project.json
index eb09487075..115a4a9192 100644
--- a/src/Microsoft.AspNetCore.Owin/project.json
+++ b/src/Microsoft.AspNetCore.Owin/project.json
@@ -8,7 +8,9 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -16,6 +18,10 @@
   },
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {}
+    "netstandard1.3": {
+      "imports": [
+        "dotnet5.4"
+      ]
+    }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.AspNetCore.WebUtilities/project.json b/src/Microsoft.AspNetCore.WebUtilities/project.json
index 6056e9e234..d186352ed5 100644
--- a/src/Microsoft.AspNetCore.WebUtilities/project.json
+++ b/src/Microsoft.AspNetCore.WebUtilities/project.json
@@ -8,7 +8,9 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {
@@ -22,12 +24,15 @@
         "System.Runtime": ""
       }
     },
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
         "System.Collections": "4.0.11-*",
         "System.IO": "4.1.0-*",
         "System.IO.FileSystem": "4.0.1-*"
-      }
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/src/Microsoft.Net.Http.Headers/project.json b/src/Microsoft.Net.Http.Headers/project.json
index 84faa09df2..6f42f8cd38 100644
--- a/src/Microsoft.Net.Http.Headers/project.json
+++ b/src/Microsoft.Net.Http.Headers/project.json
@@ -8,13 +8,15 @@
   "compilationOptions": {
     "warningsAsErrors": true,
     "keyFile": "../../tools/Key.snk",
-    "nowarn": [ "CS1591" ],
+    "nowarn": [
+      "CS1591"
+    ],
     "xmlDoc": true
   },
   "dependencies": {},
   "frameworks": {
     "net451": {},
-    "dotnet5.4": {
+    "netstandard1.3": {
       "dependencies": {
         "System.Collections": "4.0.11-*",
         "System.Diagnostics.Contracts": "4.0.1-*",
@@ -23,7 +25,10 @@
         "System.Linq": "4.1.0-*",
         "System.Text.Encoding": "4.0.11-*",
         "System.Resources.ResourceManager": "4.0.1-*"
-      }
+      },
+      "imports": [
+        "dotnet5.4"
+      ]
     }
   }
-}
+}
\ No newline at end of file
diff --git a/test/Microsoft.AspNetCore.Http.Abstractions.Tests/project.json b/test/Microsoft.AspNetCore.Http.Abstractions.Tests/project.json
index 846093b4e5..2a7298f1c4 100644
--- a/test/Microsoft.AspNetCore.Http.Abstractions.Tests/project.json
+++ b/test/Microsoft.AspNetCore.Http.Abstractions.Tests/project.json
@@ -10,11 +10,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.AspNetCore.Http.Extensions.Tests/project.json b/test/Microsoft.AspNetCore.Http.Extensions.Tests/project.json
index e49084a32a..61a7d6fbb7 100644
--- a/test/Microsoft.AspNetCore.Http.Extensions.Tests/project.json
+++ b/test/Microsoft.AspNetCore.Http.Extensions.Tests/project.json
@@ -7,11 +7,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.AspNetCore.Http.Features.Tests/project.json b/test/Microsoft.AspNetCore.Http.Features.Tests/project.json
index a454ccb613..0355df49c7 100644
--- a/test/Microsoft.AspNetCore.Http.Features.Tests/project.json
+++ b/test/Microsoft.AspNetCore.Http.Features.Tests/project.json
@@ -5,11 +5,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.AspNetCore.Http.Tests/project.json b/test/Microsoft.AspNetCore.Http.Tests/project.json
index 8d8a94cb21..ad9de0498f 100644
--- a/test/Microsoft.AspNetCore.Http.Tests/project.json
+++ b/test/Microsoft.AspNetCore.Http.Tests/project.json
@@ -5,11 +5,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.AspNetCore.Owin.Tests/project.json b/test/Microsoft.AspNetCore.Owin.Tests/project.json
index 71ede3cb4f..73a7301871 100644
--- a/test/Microsoft.AspNetCore.Owin.Tests/project.json
+++ b/test/Microsoft.AspNetCore.Owin.Tests/project.json
@@ -7,11 +7,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.AspNetCore.WebUtilities.Tests/HttpResponseStreamWriterTest.cs b/test/Microsoft.AspNetCore.WebUtilities.Tests/HttpResponseStreamWriterTest.cs
index 4f7a6d378f..372525731d 100644
--- a/test/Microsoft.AspNetCore.WebUtilities.Tests/HttpResponseStreamWriterTest.cs
+++ b/test/Microsoft.AspNetCore.WebUtilities.Tests/HttpResponseStreamWriterTest.cs
@@ -312,7 +312,7 @@ namespace Microsoft.AspNetCore.WebUtilities.Test
 
         [Theory]
         [InlineData("你好世界", "utf-16")]
-#if !DNXCORE50
+#if !NETSTANDARDAPP1_5
         // CoreCLR does not like shift_jis as an encoding.
         [InlineData("こんにちは世界", "shift_jis")]
 #endif
@@ -343,7 +343,7 @@ namespace Microsoft.AspNetCore.WebUtilities.Test
         [InlineData('你', 1023, "utf-16")]
         [InlineData('你', 1024, "utf-16")]
         [InlineData('你', 1050, "utf-16")]
-#if !DNXCORE50
+#if !NETSTANDARDAPP1_5
         // CoreCLR does not like shift_jis as an encoding.
         [InlineData('こ', 1023, "shift_jis")]
         [InlineData('こ', 1024, "shift_jis")]
diff --git a/test/Microsoft.AspNetCore.WebUtilities.Tests/project.json b/test/Microsoft.AspNetCore.WebUtilities.Tests/project.json
index 26b48e2b10..8e97596364 100644
--- a/test/Microsoft.AspNetCore.WebUtilities.Tests/project.json
+++ b/test/Microsoft.AspNetCore.WebUtilities.Tests/project.json
@@ -9,12 +9,15 @@
   },
   "testRunner": "xunit",
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "System.Text.Encoding.Extensions": "4.0.11-*",
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {
diff --git a/test/Microsoft.Net.Http.Headers.Tests/project.json b/test/Microsoft.Net.Http.Headers.Tests/project.json
index d8145f7161..7659408685 100644
--- a/test/Microsoft.Net.Http.Headers.Tests/project.json
+++ b/test/Microsoft.Net.Http.Headers.Tests/project.json
@@ -6,11 +6,14 @@
     "xunit": "2.1.0"
   },
   "frameworks": {
-    "dnxcore50": {
+    "netstandardapp1.5": {
       "dependencies": {
         "dotnet-test-xunit": "1.0.0-dev-*"
       },
-      "imports": "portable-net451+win8"
+      "imports": [
+        "dnxcore50",
+        "portable-net451+win8"
+      ]
     },
     "net451": {
       "frameworkAssemblies": {