Dev tools · alternatives · 2026

24 alternatives to MergerJS

Yet another CLI build tool to bundle JavaScript files

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. MergerJS launched in 2019; newer entries below may have overtaken it.

1. 1IM
   I made a CLI tool to create web extensions with no build configuration▲381

   Hello HN! I'm the creator and solo developer of Extension.js, a development tool for browser extensions with built-in support for TypeScript, WebAssembly, React, and modern JavaScript. Developers use it to spend less time configuring the compilation config or learning new frameworks and more time actually writing code. Most projects similar to Extension.js rely on some sort of abstraction or configuration to get started, making the initial development process slow given the extra learning curve and setup guidelines. By using Extension.js, adding the package to your npm scripts is all it…

   2024 · github.com · its alternatives →

2. 2
   Bun▲303

   A fast JS runtime Node.js replacement with built‑in tools

   Dec 2025 · bun.com · its alternatives →

3. 3
   bundlejs▲90

   An online bundler and an npm package size checker

   2021 · its alternatives →

4. 4
   bundlejs api▲68

   API to bundle, treeshake and check npm package sizes

   2023 · its alternatives →

5. 5
   ReexJs CLI▲65

   A fast way to build react.js and next.js applications

   2021 · its alternatives →

6. 6AS
   A simple website for my JavaScript bundler▲55

   2021 · fjbundler.com · its alternatives →

7. 7
   Blitz.js▲270

   Rails-like framework for React apps, built on Next.js

   2020 · its alternatives →

8. 8LA
   libmodulor – An opinionated TS library to build multi-platform apps▲51

   Initially I started building this for my own projects. The main goal was to define a unified "blueprint" allowing me to develop multi-platform apps using the same code, without code generation. I wanted to be able to develop the same functionality on web, desktop, cli, server, mobile, whatever... I've been able to achieve this by relying on TypeScript, a 4-layer architecture (UseCase => App => Product => Target) and dependency injection. This mechanism allows me to use whatever tech stack I want, provided the good adapters are developed. For instance, I have pre-built ones : node express…

   2025 · github.com · its alternatives →

9. 9CF
   CLI for trying out Node.js modules easier▲58

   2016 · github.com · its alternatives →

10. 10CF
    CLJS Fiddle – ClojureScript▲82

    2016 · cljsfiddle.com · its alternatives →

11. 11
    JavaScript Air: webpack▲63

    Learn about an amazing JavaScript bundler called webpack.

    2016 · its alternatives →

12. 12SJ
    Swap.js – a JavaScript micro-framework (HTML fragments over the wire)▲127

    Hi HN! I created this lib in the need of a simple and tiny framework to easily do AJAX-style navigation / replacement of fragments in the page, in a web application. For people who don't want to use client-side-rendering and complex frameworks à la React, there are nowadays a few "HTML-over-the-wire" libraries, like HTMX, Unpoly or this super-tiny one Swap.js :) One other key thing is that no external tool is needed: no bundler, no webpack, no TypeScript compiler, no minification needed. Just write HTML, JS (+ your preferred server-side language: PHP, Python, etc.) and it works. The…

    2023 · github.com · its alternatives →

13. 13
    Crust – A CLI framework for TypeScript and Bun▲95

    We've been building Crust (https://crustjs.com/), a TypeScript-first, Bun-native CLI framework with zero dependencies. It's been powering our core product internally for a while, and we're now open-sourcing it. The problem we kept running into: existing CLI frameworks in the JS ecosystem are either minimal arg parsers where you wire everything yourself, or heavyweight frameworks with large dependency trees and Node-era assumptions. We wanted something in between. What Crust does differently: - Full type inference from definitions — args and flags are inferred automatically. No…

    Mar 2026 · github.com · its alternatives →

14. 14
    Essential JS 2▲82

    60+ stunning, feature-rich JavaScript UI controls

    2019 · its alternatives →

15. 15FA
    Fez, a file-based build tool for JavaScript▲70

    2014 · isaacbw.com · its alternatives →

16. 16
    Total.js Platform▲93

    Open-source JavaScript platform

    2021 · its alternatives →

17. 17CP
    Clojure parser and core library in JavaScript, live on CodeCombat▲57

    2014 · vickychijwani.github.io · its alternatives →

18. 18
    ScopeBundler▲6

    Organize JavaScript code without import statements

    Dec 2025 · scopebundler.com · its alternatives →

19. 19
    Merge JSON▲5

    50+ free JSON tools that run entirely in your browser

    Jun 2026 · mergejsonfiles.com · its alternatives →

20. 20FJ
    Fuse.js: The opinionated framework for creating typesafe data layers▲11

    2023 · stellate.co · its alternatives →

21. 21IM
    I made a tool to migrate from CommonJS to ESM▲12

    2023 · github.com · its alternatives →

22. 22CA
    ClavaScript: a ClojureScript syntax to JavaScript compiler▲24

    2022 · github.com · its alternatives →

23. 23WJ
    Webclone.js – A simple tool to clone websites▲24

    I needed a lightweight way to archive documentation from a website. wget and similar tools failed to clone the site reliably (missing assets, broken links, etc.), so I ended up building a full website-cloning tool using Node.js + Puppeteer. Repo: https://github.com/jademsee/webclone Feedback, issues, and PRs are very welcome.

    Dec 2025 · github.com · its alternatives →

24. 24JB
    Jsbundler – Bundle npm packages and use them in the browser▲16

    2015 · jsbundler.com · its alternatives →

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →