diff --git a/2023/d12/ex1/ex1.py b/2023/d12/ex1/ex1.py
index e713128..4e84e37 100755
--- a/2023/d12/ex1/ex1.py
+++ b/2023/d12/ex1/ex1.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 
+import functools
 import sys
 
 
@@ -10,6 +11,7 @@ def solve(input: list[str]) -> int:
             for record, groups in map(str.split, input)
         ]
 
+    @functools.cache
     def solve_line(record: str, groups: tuple[int, ...]) -> int:
         # Empty string must have no groups left, or it's not a solve
         if len(record) == 0: