diff --git a/crates/lang/src/parser.rs b/crates/lang/src/parser.rs
index d2c98f1c..d0efa9dd 100644
--- a/crates/lang/src/parser.rs
+++ b/crates/lang/src/parser.rs
@@ -1333,7 +1333,7 @@ pub fn type_parser() -> impl Parser<Token, ast::Annotation, Error = ParseError>
                     r.clone()
                         .separated_by(just(Token::Comma))
                         .allow_trailing()
-                        .delimited_by(just(Token::LeftParen), just(Token::RightParen))
+                        .delimited_by(just(Token::Less), just(Token::Greater))
                         .or_not(),
                 )
                 .map_with_span(|(name, arguments), span| ast::Annotation::Constructor {
@@ -1399,7 +1399,7 @@ pub fn type_name_with_args() -> impl Parser<Token, (String, Option<Vec<String>>)
             select! {Token::Name { name } => name}
                 .separated_by(just(Token::Comma))
                 .allow_trailing()
-                .delimited_by(just(Token::LeftParen), just(Token::RightParen))
+                .delimited_by(just(Token::Less), just(Token::Greater))
                 .or_not(),
         ),
     )
diff --git a/crates/lang/src/tests/parser.rs b/crates/lang/src/tests/parser.rs
index 44227431..cbadcbf8 100644
--- a/crates/lang/src/tests/parser.rs
+++ b/crates/lang/src/tests/parser.rs
@@ -92,7 +92,7 @@ fn import_alias() {
 #[test]
 fn custom_type() {
     let code = indoc! {r#"
-        type Option(a) {
+        type Option<a> {
           Some(a, Int)
           None
           Wow { name: Int, age: Int }
@@ -225,7 +225,7 @@ fn opaque_type() {
 #[test]
 fn type_alias() {
     let code = indoc! {r#"
-        type Thing = Option(Int)
+        type Thing = Option<Int>
     "#};
 
     assert_definition(
@@ -255,7 +255,7 @@ fn type_alias() {
 #[test]
 fn pub_type_alias() {
     let code = indoc! {r#"
-        pub type Me = Option(String)
+        pub type Me = Option<String>
     "#};
 
     assert_definition(