diff --git a/build.fsx b/build.fsx
index 72a9f526..b808add4 100644
--- a/build.fsx
+++ b/build.fsx
@@ -423,16 +423,16 @@ Target "TestF#NET46" (fun _ -> testLibraryFsharp "net46")
 Target "TestF#NET47" (fun _ -> testLibraryFsharp "net47")
 
 "Build" ==> "TestF#Core1.1" ==> "TestF#"
-"Build" ==> "TestF#Core2.0" //==> "TestF#"
-"Build" ==> "TestF#NET45" ==> "TestF#"
-"Build" ==> "TestF#NET46" //==> "TestF#"
-"Build" ==> "TestF#NET47" //==> "TestF#"
+"Build" ==> "TestF#Core2.0"
+"Build" =?> ("TestF#NET45", isWindows) ==> "TestF#"
+"Build" =?> ("TestF#NET46", isWindows)
+"Build" =?> ("TestF#NET47", isWindows)
 "Build" ==> "TestC#Core1.1" ==> "TestC#"
-"Build" ==> "TestC#Core2.0" //==> "TestC#"
-"Build" ==> "TestC#NET40" //==> "TestC#"
-"Build" ==> "TestC#NET45" ==> "TestC#"
-"Build" ==> "TestC#NET46" //==> "TestC#"
-"Build" ==> "TestC#NET47" //==> "TestC#"
+"Build" ==> "TestC#Core2.0"
+"Build" =?> ("TestC#NET40", isWindows)
+"Build" =?> ("TestC#NET45", isWindows) ==> "TestC#"
+"Build" =?> ("TestC#NET46", isWindows)
+"Build" =?> ("TestC#NET47", isWindows)
 "TestC#" ==> "Test"
 "TestF#" ==> "Test"