diff --git a/.changeset/two-drinks-check.md b/.changeset/two-drinks-check.md
new file mode 100644
index 0000000000..6cea204da0
--- /dev/null
+++ b/.changeset/two-drinks-check.md
@@ -0,0 +1,5 @@
+---
+"@nomicfoundation/slang": patch
+---
+
+fix a bug where CST nodes are invalidated after using AST types
diff --git a/crates/codegen/runtime/cargo/wasm/src/runtime/interface/ast.wit.jinja2 b/crates/codegen/runtime/cargo/wasm/src/runtime/interface/ast.wit.jinja2
index 2aceef75c9..7a63444bd2 100644
--- a/crates/codegen/runtime/cargo/wasm/src/runtime/interface/ast.wit.jinja2
+++ b/crates/codegen/runtime/cargo/wasm/src/runtime/interface/ast.wit.jinja2
@@ -2,9 +2,9 @@ interface ast {
     use cst.{node, nonterminal-node};
 
     resource selectors {
-        sequence: static func(node: nonterminal-node) -> result<list<option<node>>, string>;
-        choice: static func(node: nonterminal-node) -> result<node, string>;
-        repeated: static func(node: nonterminal-node) -> result<list<node>, string>;
-        separated: static func(node: nonterminal-node) -> result<list<list<node>>, string>;
+        sequence: static func(node: borrow<nonterminal-node>) -> result<list<option<node>>, string>;
+        choice: static func(node: borrow<nonterminal-node>) -> result<node, string>;
+        repeated: static func(node: borrow<nonterminal-node>) -> result<list<node>, string>;
+        separated: static func(node: borrow<nonterminal-node>) -> result<list<list<node>>, string>;
     }
 }
diff --git a/crates/codegen/runtime/cargo/wasm/src/runtime/interface/generated/ast.wit b/crates/codegen/runtime/cargo/wasm/src/runtime/interface/generated/ast.wit
index 31c6a91f88..16ed171036 100644
--- a/crates/codegen/runtime/cargo/wasm/src/runtime/interface/generated/ast.wit
+++ b/crates/codegen/runtime/cargo/wasm/src/runtime/interface/generated/ast.wit
@@ -4,9 +4,9 @@ interface ast {
     use cst.{node, nonterminal-node};
 
     resource selectors {
-        sequence: static func(node: nonterminal-node) -> result<list<option<node>>, string>;
-        choice: static func(node: nonterminal-node) -> result<node, string>;
-        repeated: static func(node: nonterminal-node) -> result<list<node>, string>;
-        separated: static func(node: nonterminal-node) -> result<list<list<node>>, string>;
+        sequence: static func(node: borrow<nonterminal-node>) -> result<list<option<node>>, string>;
+        choice: static func(node: borrow<nonterminal-node>) -> result<node, string>;
+        repeated: static func(node: borrow<nonterminal-node>) -> result<list<node>, string>;
+        separated: static func(node: borrow<nonterminal-node>) -> result<list<list<node>>, string>;
     }
 }
diff --git a/crates/codegen/runtime/cargo/wasm/src/runtime/wrappers/ast/mod.rs b/crates/codegen/runtime/cargo/wasm/src/runtime/wrappers/ast/mod.rs
index 1a4b3c6eee..10b4fb6b87 100644
--- a/crates/codegen/runtime/cargo/wasm/src/runtime/wrappers/ast/mod.rs
+++ b/crates/codegen/runtime/cargo/wasm/src/runtime/wrappers/ast/mod.rs
@@ -8,7 +8,7 @@ mod ffi {
         Guest, GuestSelectors,
     };
     pub use crate::wasm_crate::bindings::exports::nomic_foundation::slang::cst::{
-        Node, NonterminalNode,
+        Node, NonterminalNodeBorrow,
     };
 }
 
@@ -27,25 +27,25 @@ impl ffi::Guest for crate::wasm_crate::World {
 pub struct SelectorsWrapper;
 
 impl ffi::GuestSelectors for SelectorsWrapper {
-    fn sequence(node: ffi::NonterminalNode) -> Result<Vec<Option<ffi::Node>>, String> {
+    fn sequence(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Option<ffi::Node>>, String> {
         Ok(selectors::select_sequence(node._borrow_ffi())?
             .into_iter()
             .map(|opt| opt.map(|node| node._into_ffi()))
             .collect())
     }
 
-    fn choice(node: ffi::NonterminalNode) -> Result<ffi::Node, String> {
+    fn choice(node: ffi::NonterminalNodeBorrow<'_>) -> Result<ffi::Node, String> {
         Ok(selectors::select_choice(node._borrow_ffi())?._into_ffi())
     }
 
-    fn repeated(node: ffi::NonterminalNode) -> Result<Vec<ffi::Node>, String> {
+    fn repeated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<ffi::Node>, String> {
         Ok(selectors::select_repeated(node._borrow_ffi())?
             .into_iter()
             .map(|node| node._into_ffi())
             .collect())
     }
 
-    fn separated(node: ffi::NonterminalNode) -> Result<Vec<Vec<ffi::Node>>, String> {
+    fn separated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Vec<ffi::Node>>, String> {
         Ok(selectors::select_separated(node._borrow_ffi())?
             .into_iter()
             .map(|vec| vec.into_iter().map(|node| node._into_ffi()).collect())
diff --git a/crates/solidity/outputs/cargo/wasm/src/generated/interface/generated/ast.wit b/crates/solidity/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
index 31c6a91f88..16ed171036 100644
--- a/crates/solidity/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
+++ b/crates/solidity/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
@@ -4,9 +4,9 @@ interface ast {
     use cst.{node, nonterminal-node};
 
     resource selectors {
-        sequence: static func(node: nonterminal-node) -> result<list<option<node>>, string>;
-        choice: static func(node: nonterminal-node) -> result<node, string>;
-        repeated: static func(node: nonterminal-node) -> result<list<node>, string>;
-        separated: static func(node: nonterminal-node) -> result<list<list<node>>, string>;
+        sequence: static func(node: borrow<nonterminal-node>) -> result<list<option<node>>, string>;
+        choice: static func(node: borrow<nonterminal-node>) -> result<node, string>;
+        repeated: static func(node: borrow<nonterminal-node>) -> result<list<node>, string>;
+        separated: static func(node: borrow<nonterminal-node>) -> result<list<list<node>>, string>;
     }
 }
diff --git a/crates/solidity/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs b/crates/solidity/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
index 5b262a1782..cf50ecacd2 100644
--- a/crates/solidity/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
+++ b/crates/solidity/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
@@ -10,7 +10,7 @@ mod ffi {
         Guest, GuestSelectors,
     };
     pub use crate::wasm_crate::bindings::exports::nomic_foundation::slang::cst::{
-        Node, NonterminalNode,
+        Node, NonterminalNodeBorrow,
     };
 }
 
@@ -29,25 +29,25 @@ impl ffi::Guest for crate::wasm_crate::World {
 pub struct SelectorsWrapper;
 
 impl ffi::GuestSelectors for SelectorsWrapper {
-    fn sequence(node: ffi::NonterminalNode) -> Result<Vec<Option<ffi::Node>>, String> {
+    fn sequence(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Option<ffi::Node>>, String> {
         Ok(selectors::select_sequence(node._borrow_ffi())?
             .into_iter()
             .map(|opt| opt.map(|node| node._into_ffi()))
             .collect())
     }
 
-    fn choice(node: ffi::NonterminalNode) -> Result<ffi::Node, String> {
+    fn choice(node: ffi::NonterminalNodeBorrow<'_>) -> Result<ffi::Node, String> {
         Ok(selectors::select_choice(node._borrow_ffi())?._into_ffi())
     }
 
-    fn repeated(node: ffi::NonterminalNode) -> Result<Vec<ffi::Node>, String> {
+    fn repeated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<ffi::Node>, String> {
         Ok(selectors::select_repeated(node._borrow_ffi())?
             .into_iter()
             .map(|node| node._into_ffi())
             .collect())
     }
 
-    fn separated(node: ffi::NonterminalNode) -> Result<Vec<Vec<ffi::Node>>, String> {
+    fn separated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Vec<ffi::Node>>, String> {
         Ok(selectors::select_separated(node._borrow_ffi())?
             .into_iter()
             .map(|vec| vec.into_iter().map(|node| node._into_ffi()).collect())
diff --git a/crates/testlang/outputs/cargo/wasm/src/generated/interface/generated/ast.wit b/crates/testlang/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
index 31c6a91f88..16ed171036 100644
--- a/crates/testlang/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
+++ b/crates/testlang/outputs/cargo/wasm/src/generated/interface/generated/ast.wit
@@ -4,9 +4,9 @@ interface ast {
     use cst.{node, nonterminal-node};
 
     resource selectors {
-        sequence: static func(node: nonterminal-node) -> result<list<option<node>>, string>;
-        choice: static func(node: nonterminal-node) -> result<node, string>;
-        repeated: static func(node: nonterminal-node) -> result<list<node>, string>;
-        separated: static func(node: nonterminal-node) -> result<list<list<node>>, string>;
+        sequence: static func(node: borrow<nonterminal-node>) -> result<list<option<node>>, string>;
+        choice: static func(node: borrow<nonterminal-node>) -> result<node, string>;
+        repeated: static func(node: borrow<nonterminal-node>) -> result<list<node>, string>;
+        separated: static func(node: borrow<nonterminal-node>) -> result<list<list<node>>, string>;
     }
 }
diff --git a/crates/testlang/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs b/crates/testlang/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
index 5b262a1782..cf50ecacd2 100644
--- a/crates/testlang/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
+++ b/crates/testlang/outputs/cargo/wasm/src/generated/wrappers/ast/mod.rs
@@ -10,7 +10,7 @@ mod ffi {
         Guest, GuestSelectors,
     };
     pub use crate::wasm_crate::bindings::exports::nomic_foundation::slang::cst::{
-        Node, NonterminalNode,
+        Node, NonterminalNodeBorrow,
     };
 }
 
@@ -29,25 +29,25 @@ impl ffi::Guest for crate::wasm_crate::World {
 pub struct SelectorsWrapper;
 
 impl ffi::GuestSelectors for SelectorsWrapper {
-    fn sequence(node: ffi::NonterminalNode) -> Result<Vec<Option<ffi::Node>>, String> {
+    fn sequence(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Option<ffi::Node>>, String> {
         Ok(selectors::select_sequence(node._borrow_ffi())?
             .into_iter()
             .map(|opt| opt.map(|node| node._into_ffi()))
             .collect())
     }
 
-    fn choice(node: ffi::NonterminalNode) -> Result<ffi::Node, String> {
+    fn choice(node: ffi::NonterminalNodeBorrow<'_>) -> Result<ffi::Node, String> {
         Ok(selectors::select_choice(node._borrow_ffi())?._into_ffi())
     }
 
-    fn repeated(node: ffi::NonterminalNode) -> Result<Vec<ffi::Node>, String> {
+    fn repeated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<ffi::Node>, String> {
         Ok(selectors::select_repeated(node._borrow_ffi())?
             .into_iter()
             .map(|node| node._into_ffi())
             .collect())
     }
 
-    fn separated(node: ffi::NonterminalNode) -> Result<Vec<Vec<ffi::Node>>, String> {
+    fn separated(node: ffi::NonterminalNodeBorrow<'_>) -> Result<Vec<Vec<ffi::Node>>, String> {
         Ok(selectors::select_separated(node._borrow_ffi())?
             .into_iter()
             .map(|vec| vec.into_iter().map(|node| node._into_ffi()).collect())
diff --git a/crates/testlang/outputs/npm/tests/src/tests/ast/ast.mts b/crates/testlang/outputs/npm/tests/src/tests/ast/ast.mts
index e85b9e0450..66d31e04f9 100644
--- a/crates/testlang/outputs/npm/tests/src/tests/ast/ast.mts
+++ b/crates/testlang/outputs/npm/tests/src/tests/ast/ast.mts
@@ -201,3 +201,22 @@ test("create and use binary expressions", () => {
   assertIsTerminalNode(operator, TerminalKind.Plus, "+");
   assertIsTerminalNode(rightOperand.variant, TerminalKind.Identifier, "bar");
 });
+
+it("can reuse the same CST nodes after selectors", () => {
+  // Bug: https://github.com/NomicFoundation/slang/issues/1128
+
+  const source = `foo + bar`;
+
+  const parser = Parser.create("1.0.0");
+  const parseOutput = parser.parse(NonterminalKind.SourceUnit, source);
+  parseOutput.isValid(); // true
+
+  const cst = parseOutput.tree.asNonterminalNode()!;
+  const ast = new SourceUnit(cst);
+
+  expect(ast.cst.kind).toBe(NonterminalKind.SourceUnit);
+
+  expect(ast.members.cst.kind).toBe(NonterminalKind.SourceUnitMembers);
+
+  expect(ast.cst.kind).toBe(NonterminalKind.SourceUnit);
+});