Postmodern immutable and persistent data structures for C++ — value semantics at scale

A high-performance immutable mapping type for Python.

Data structure and algorithm library for go, designed to provide functions similar to C++ STL

Immutable and Memory-Efficient Maps and Sets in Go

Hash Array Mapped Trie (HAMT) implemented in Go (1.18+ generics)

Library providing fast hash based immutable map and set

An implementation of HAMT data-structure in Swift

Persistent HashMap for TypeScript

Purely functional data structures in Java

Mutable and immutable persistent maps and sets as hash array mapped trie (HAMT) for FreePascal

HAMT implementation whose sub-trees can be shared over threads

Hash Array Mapped Trie as defined in Phil Bagwell (2001). Ideal Hash Tries

Providing fast at scale HashMap, LinkedHashMap, and Higher Order Functions to any iterable, such as Array, Map or Set. Tested, and Benchmarked, Issues & PRs welcomed.

Haskell implementations of associative containers (maps / dictionaries) which retire elements in least recently used (LRU) order when growing past a specified limit

persistent data structures in common lisp "pers-i-DAH-strick-el"

Draft specification for bit popcount in JavaScript.

Immutable Persistent Map for Go

Permafrost implements a (relatively) fast unordered persistent map, set, bidirectional map for Crystal

A hash array-mapped trie implementation in C adapted for raku with MoarVM. (Ongoing work)

PHP immutable persistent data structures library