Top 4 effect-system Open-Source Projects

effect

25 4,370 9.9 TypeScript

A fully-fledged functional effect system for TypeScript with a rich standard library

Project mention: Exploring Effect, a meta-state RxJS-like framework | dev.to | 2024-01-24

Effect is a functional library for building and composing asynchronous, concurrent, and reactive programs in TypeScript. It focuses on providing a robust and type-safe way to manage side effects in your programs.

effectful

21 329 8.0 Haskell

An easy to use, fast extensible effects library with seamless integration with the existing Haskell ecosystem.

Project mention: Haskell in Production: Standard Chartered | news.ycombinator.com | 2023-05-03

Also a much simpler alternative in my opinion to monad transformers is effectful:
https://github.com/haskell-effectful/effectful
Here's a talk on it:
https://www.youtube.com/watch?v=BUoYKBLOOrE

SurveyJS

surveyjs.io sponsored

Open-Source JSON Form Builder to Create Dynamic Forms Right in Your App. With SurveyJS form UI libraries, you can build and style forms in a fully-integrated drag & drop form builder, render them in your JS app, and store form submission data in any backend, inc. PHP, ASP.NET Core, and Node.js.
zio-direct

3 149 1.8 Scala

Direct-Style Programming for ZIO
pfun

3 146 6.5 Python

Functional, composable, asynchronous, type-safe Python.

NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020).