diff --git a/src/app/FakeLib/Globbing/FileSystem.fs b/src/app/FakeLib/Globbing/FileSystem.fs
index db23d1ed678..73d23a2eae0 100644
--- a/src/app/FakeLib/Globbing/FileSystem.fs
+++ b/src/app/FakeLib/Globbing/FileSystem.fs
@@ -89,4 +89,8 @@ let inline (++) (x:FileIncludes) pattern = x.And pattern
 let inline (--) (x:FileIncludes) pattern = x.ButNot pattern
 
 /// Includes a single pattern and scans the files - !! x = AllFilesMatching x
-let inline (!!) x = Include x
\ No newline at end of file
+let inline (!!) x = Include x
+
+/// Include prefix operator
+[<Obsolete("!+ is obsolete - use !! instead")>]
+let inline (!+) x = Include x
\ No newline at end of file