diff --git a/src/compiler/factory/nodeChildren.ts b/src/compiler/factory/nodeChildren.ts
index 79e8563f6f5..fa77de189fc 100644
--- a/src/compiler/factory/nodeChildren.ts
+++ b/src/compiler/factory/nodeChildren.ts
@@ -4,18 +4,25 @@ import {
     Node,
 } from "../_namespaces/ts.js";
 
-const nodeChildren = new WeakMap<Node, readonly Node[] | undefined>();
+// Why var? It avoids TDZ checks in the runtime which can be costly.
+// See: https://github.com/microsoft/TypeScript/issues/52924
+/* eslint-disable no-var */
+var nodeChildren = new WeakMap<Node, readonly Node[] | undefined>();
+var nodeChildrenGet = nodeChildren.get.bind(nodeChildren);
+var nodeChildrenSet = nodeChildren.set.bind(nodeChildren);
+/* eslint-enable no-var */
+
 
 /** @internal */
 export function getNodeChildren(node: Node): readonly Node[] | undefined {
     if (!isNodeKind(node.kind)) return emptyArray;
 
-    return nodeChildren.get(node);
+    return nodeChildrenGet(node);
 }
 
 /** @internal */
 export function setNodeChildren(node: Node, children: readonly Node[]): readonly Node[] {
-    nodeChildren.set(node, children);
+    nodeChildrenSet(node, children);
     return children;
 }