diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index a9c347e4..15ece00e 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -1401,6 +1401,7 @@ R:
   primary_extension: .r
   extensions:
   - .R
+  - .rsx
   filenames:
   - .Rprofile
   interpreters: