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  1. Stackups
  2. DevOps
  3. Build Automation
  4. Javascript Build Tools
  5. Just vs System.js

Just vs System.js

OverviewDecisionsComparisonAlternatives

Overview

System.js
System.js
Stacks28
Followers10
Votes2
GitHub Stars13.1K
Forks1.1K
Just
Just
Stacks31
Followers13
Votes0
GitHub Stars2.0K
Forks92

Just vs System.js: What are the differences?

What is Just? A library that organizes build tasks for your JS projects. It is a build task definition library. It stands on the shoulders of two excellent and well tested libraries: undertaker and yargs. It also provides what we call "stacks" to complete the workflow of building a repository.

What is System.js? Dynamic ES module loader. It is a Universal Module Loader for JavaScript. If you've used RequireJs or a CommonJs bundler in the past, you have probably created modules.Configurable module loader enabling dynamic ES module workflows in browsers and NodeJS.

Just and System.js can be primarily classified as "JS Build Tools / JS Task Runners" tools.

Just and System.js are both open source tools. System.js with 9.75K GitHub stars and 852 forks on GitHub appears to be more popular than Just with 1.31K GitHub stars and 44 GitHub forks.

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Advice on System.js, Just

Aleksandr
Aleksandr

Contract Software Engineer - Microsoft at Microsoft-365

Dec 23, 2019

Decided

Why migrated?

I could define the next points why we have to migrate:

  • Decrease build time of our application. (It was the main cause).
  • Also jspm install takes much more time than npm install.
  • Many config files for SystemJS and JSPM. For Webpack you can use just one main config file, and you can use some separate config files for specific builds using inheritance and merge them.
301k views301k
Comments

Detailed Comparison

System.js
System.js
Just
Just

It is a Universal Module Loader for JavaScript. If you've used RequireJs or a CommonJs bundler in the past, you have probably created modules.Configurable module loader enabling dynamic ES module workflows in browsers and NodeJS.

It is a build task definition library. It stands on the shoulders of two excellent and well tested libraries: undertaker and yargs. It also provides what we call "stacks" to complete the workflow of building a repository.

Compatibility with Webpack;Polyfills for Older Browsers;Loader Extensions
project scaffold tool
Statistics
GitHub Stars
13.1K
GitHub Stars
2.0K
GitHub Forks
1.1K
GitHub Forks
92
Stacks
28
Stacks
31
Followers
10
Followers
13
Votes
2
Votes
0
Pros & Cons
Pros
  • 1
    Great plugin system
  • 1
    Loads anything trough AMD with the right plugin
No community feedback yet
Integrations
AngularJS
AngularJS
Node.js
Node.js
jQuery
jQuery
TypeScript
TypeScript
Webpack
Webpack
JavaScript
JavaScript
Jest
Jest

What are some alternatives to System.js, Just?

gulp

gulp

Build system automating tasks: minification and copying of all JavaScript files, static images. More capable of watching files to automatically rerun the task when a file changes.

Webpack

Webpack

A bundler for javascript and friends. Packs many modules into a few bundled assets. Code Splitting allows to load parts for the application on demand. Through "loaders" modules can be CommonJs, AMD, ES6 modules, CSS, Images, JSON, Coffeescript, LESS, ... and your custom stuff.

Grunt

Grunt

The less work you have to do when performing repetitive tasks like minification, compilation, unit testing, linting, etc, the easier your job becomes. After you've configured it, a task runner can do most of that mundane work for you—and your team—with basically zero effort.

Brunch

Brunch

Brunch is an assembler for HTML5 applications. It's agnostic to frameworks, libraries, programming, stylesheet & templating languages and backend technology.

Parcel

Parcel

Parcel is a web application bundler, differentiated by its developer experience. It offers blazing fast performance utilizing multicore processing, and requires zero configuration.

rollup

rollup

It is a module bundler for JavaScript which compiles small pieces of code into something larger and more complex, such as a library or application. It uses the new standardized format for code modules included in the ES6 revision of JavaScript, instead of previous idiosyncratic solutions such as CommonJS and AMD.

Backpack

Backpack

Backpack is minimalistic build system for Node.js. Inspired by Facebook's create-react-app, Zeit's Next.js, and Remy's Nodemon, Backpack lets you create modern Node.js apps and services with zero configuration. Backpack handles all the file-watching, live-reloading, transpiling, and bundling, so you don't have to.

Vite

Vite

It is an opinionated web dev build tool that serves your code via native ES Module imports during dev and bundles it with Rollup for production.

Pingy CLI

Pingy CLI

Gulp and Grunt and other heavyweight build tools are great for complicated build workflows. Sometimes you want something simpler that doesn't take lots of configuration to get up and running. That's Pingy CLI.

Microbundle

Microbundle

Zero-configuration bundler for tiny modules, powered by Rollup.

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