You're totally right. I've updated the PR, so now it does resizing, by default when the map is at 85% capacity. This is an interesting value to explore, we may want to set it above 100%, because the array resizes by powers of two, resize increases the storage space by a lot, while keeping it high will mean traversing linked lists more. Keeping it very low will turn the data structure into mostly a linked list though, so it's a balance there. Depends on the use case..