diff --git a/TODO b/TODO
index 6d2312a..3b2f9cb 100644
--- a/TODO
+++ b/TODO
@@ -4,3 +4,4 @@
 [ ] Port font system from C to C3 (rewrite1)
 [ ] Update ARCHITECTURE.md
 [ ] Write a README.md
+[ ] Use an arena allocator for cache