also Ctrie: "a concurrent thread-safe lock-free implementation of a hash array mapped trie": https://en.wikipedia.org/wiki/Ctrie https://en.wikipedia.org/wiki/C

also Ctrie: "a concurrent thread-safe lock-free implementation of a hash array mapped trie": https://en.wikipedia.org/wiki/Ctrie https://en.wikipedia.org/wiki/Ctrie So basically like HAMT but lock free.