whatisgithub

What is monio?

getify/monio — explained in plain English

Analysis updated 2026-05-18

1,126JavaScriptAudience · developerComplexity · 4/5LicenseSetup · moderate

In one sentence

A JavaScript library of functional-programming monads (IO, Maybe, Either) for chaining side effects and async code in a predictable way.

Mindmap

mindmap
  root((Monio))
    What it does
      IO monad
      Lazy side effects
      Async chaining
    Tech stack
      JavaScript
      Node.js
      npm
    Use cases
      Wrap side effects
      Handle missing values
      Model success or failure
      React to event streams
    Audience
      FP developers
      JavaScript developers

Code map

Detail Auto

An interactive map of this repo's files and how they connect — its source is parsed live in your browser. Click Visualize to build it.

filefunction / class

What do people build with it?

USE CASE 1

Wrap side-effecting code like network calls or console output in a lazy IO monad.

USE CASE 2

Handle values that might not exist using Maybe and Just instead of null checks.

USE CASE 3

Model success or failure outcomes cleanly using the Either monad.

USE CASE 4

React to streams of events over time using the IOx reactive monad.

What is it built with?

JavaScriptNode.jsnpm

How does it compare?

getify/moniorebel0789/codexprophuc-nt/my-translator
Stars1,1261,1341,106
LanguageJavaScriptJavaScriptJavaScript
Last pushed2026-06-30
MaintenanceActive
Setup difficultymoderatemoderatemoderate
Complexity4/53/53/5
Audiencedeveloperdevelopergeneral

Figures from each repo's GitHub metadata at analysis time.

How do you get it running?

Difficulty · moderate Time to first run · 30min

Requires familiarity with functional programming and monad concepts to use effectively.

Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

So what is it?

Monio is a JavaScript library for developers who want to write code in a functional programming style, specifically using a pattern called monads. A monad is a design pattern from functional programming that helps you chain operations together in a predictable, controlled way, especially when dealing with side effects like network requests, user input, or console output. The main building block in Monio is called IO. In plain terms, IO is a container that wraps a piece of code that has a side effect, but does not run it until you explicitly say so. This lazy approach means you can build up a sequence of operations and only trigger them when ready. Monio's IO also works naturally with JavaScript promises and async code, so you can write async logic in a style that looks similar to familiar async/await code, while still getting the structural benefits of functional programming. Beyond IO, the library also provides several companion types. Maybe and Just let you work with values that might or might not exist, without constantly writing null checks. Either lets you model outcomes that are either a success or a failure. IOx is a reactive variant of IO designed for working with streams of events over time. All of these types can be combined and chained together. Monio is available as an npm package and works in Node.js as well as in browsers. It supports the standard JavaScript module formats (CommonJS, ESM, and UMD), so it fits into most existing project setups. The library is aimed at JavaScript developers who are curious about or already practicing functional programming. The README includes a detailed guide for beginners who are new to monads, along with live demo applications showing real-world usage patterns.

Copy-paste prompts

Prompt 1
Explain how Monio's IO monad works and show me a basic example.
Prompt 2
Walk me through using Maybe and Either in Monio to avoid null checks.
Prompt 3
How do I write do-style async code in Monio using IO.do?
Prompt 4
Show me an example combining Just, Maybe, and IO together in Monio.

Frequently asked questions

What is monio?

A JavaScript library of functional-programming monads (IO, Maybe, Either) for chaining side effects and async code in a predictable way.

What language is monio written in?

Mainly JavaScript. The stack also includes JavaScript, Node.js, npm.

What license does monio use?

Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

How hard is monio to set up?

Setup difficulty is rated moderate, with roughly 30min to a first successful run.

Who is monio for?

Mainly developer.

Open on GitHub → Ask about another repo

This repo across BitVibe Labs

Verify against the repo before relying on details.