diff --git a/syntax/ats.vim b/syntax/ats.vim
index 8ba3076..74072a0 100644
--- a/syntax/ats.vim
+++ b/syntax/ats.vim
@@ -22,11 +22,11 @@ syn match atsSpecial -\v\\[0-9]+-
 syn region atsString start=+"+ end=+"+ contains=atsSpecial
 
 syn keyword atsKeyword staload dynload overload with fun symintr include fn fnx and prfun prfn
-syn keyword atsKeyword lam llam fix raise of var val prval
-syn keyword atsKeywordTwo case ifcase if then else
+syn keyword atsKeyword lam llam fix raise of var val prval if then else
+syn keyword atsKeywordTwo case ifcase
 syn region atsQualName start="\$" end="\." contains=atsIdentifier
 
-syn match atsKeyword "\v[\%\+\-\<\>\=!]+"
+syn match atsKeyword "\v[\%\+\-\<\>\=!\:\~]+"
 
 syn keyword atsFixity infixr infixl prefix postfix
 
@@ -40,10 +40,13 @@ syn keyword atsType implement primplmnt extern
 
 syn match atsParens "[()]"
 
-syn match atsOperator "\v\@"
+syn match atsOperator "\v[\@\']"
 
-syn match atsMacro "\v\#.*$"
+syn region atsMacro start="#" end="\v$" contains=atsString
 
+syn keyword atsBool true false
+
+highlight link atsBool Boolean
 highlight link atsKeywordTwo Include
 highlight link atsQualName Include
 highlight link atsArrow Special