@@ -327,8 +327,13 @@ let isMatchingOperatingSystem (operatingSystemFilter : string option) =
 let isMatchingPlatform (operatingSystemFilter : string option) =
     match operatingSystemFilter with
     | None -> true
+#if NETSTANDARD1_6 || NETSTANDARD2_0
+    | Some filter when filter = "mono" -> isMacOS || isUnix
+    | Some filter when filter = "windows" -> isWindows
+#else
     | Some filter when filter = "mono" -> isMonoRuntime
     | Some filter when filter = "windows" -> not isMonoRuntime
+#endif
     | _ -> isMatchingOperatingSystem operatingSystemFilter
 
 /// [omit]
@@ -896,4 +901,4 @@ module List =
 module Task =
 
     let Map<'TIn,'TOut> (mapper : 'TIn -> 'TOut) (t:Task<'TIn>) : Task<'TOut> =
-        t.ContinueWith((fun (t:Task<'TIn>) -> mapper(t.Result)))
+        t.ContinueWith((fun (t:Task<'TIn>) -> mapper(t.Result)))