diff --git a/lib/parse.js b/lib/parse.js
index 145ea26..2285b52 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -39,6 +39,22 @@ const parse = (input, options = {}) => {
     throw new SyntaxError(`Input length (${input.length}), exceeds max characters (${max})`);
   }
 
+  let braceStack = [];
+  for (const char of input) {
+    if (char === '{') {
+      braceStack.push('{');
+    } else if (char === '}') {
+      if (braceStack.length === 0) {
+        throw new SyntaxError("Mismatched closing brace found");
+      }
+      braceStack.pop();
+    }
+  }
+  
+  if (braceStack.length > 0) {
+    throw new SyntaxError("Mismatched open brace found");
+  }
+
   let ast = { type: 'root', input, nodes: [] };
   let stack = [ast];
   let block = ast;