The Functional toolkit for Kotlin HTTP applications. http4k provides a simple and uniform way to serve, consume, and test HTTP services.

Pattern Matching for Javascript

Efficient immutable updates, 2-6x faster than naive handcrafted reducer, and more than 10x faster than Immer.

ESLint rules to disable mutation and promote fp in JavaScript and TypeScript.

A MobX powered state management solution based on data trees with first class support for Typescript, support for snapshots, patches and much more

Don't Fear the Profunctor Optics!

Docile keeps your Ruby DSLs tame and well-behaved

TSLint rules to disable mutation in TypeScript.

A very fast and lightweight Typescript library to create immutable states with a mutable syntax

State management for React

Functional programming, immutable collections and FP constructs for typescript and javascript

⚡️ λ PHP functional library focused on simplicity and performance

ABRoot is a utility that provides full immutability and atomicity to a Linux system, by transacting between two root filesystems. Updates are performed using OCI images, to ensure that the system is always in a consistent state.

Generic, Null-safe, Immutable Collections and Functional Transformations for the JVM

The Chaos Programming Language

Build Virtual Machine Image from Dockerfile or Docker image

Immutable Package Manager

The immutable/mutable meta-distribution (universal bootstrapper)

[Python] Stream-like manipulation of iterables.

A tiny immutable store with type safety.