diff --git a/syntax/ats.vim b/syntax/ats.vim
index eaf1e67..0a8b53d 100644
--- a/syntax/ats.vim
+++ b/syntax/ats.vim
@@ -32,7 +32,7 @@ syn match atsArrow '=/=>'
 syn region atsArrow start="=<" end=">" contains=arrowContents
 syn region atsArrow start="-<" end=">"
 
-syn keyword atsType void bool string char int uint charNZ strnptr Strptr0 Strptr1 nat
+syn keyword atsType void bool string char int uint charNZ strnptr Strptr0 Strptr1 nat lint ulint
 syn keyword atsType datavtype datatype vtypedef dataviewtype viewtypdef typedef view viewdef dataview abstype absvtype absviewtype datasort dataprop
 syn keyword atsType implement primplmnt extern