Life & fun · alternatives · 2026

24 alternatives to Design by Contract for JavaScript

Design by Contract for JavaScript via a Babel plugin. - codemix/babel-plugin-contracts

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Design by Contract for JavaScript launched in 2015; newer entries below may have overtaken it.

1. 1
   JSX.Design▲413

   The dev friendly no-code editor for React development

   2024 · its alternatives →

2. 2
   Layouts.dev▲699

   A notebook for building interfaces with Tailwind & shadcn/UI

   2024 · layouts.dev · its alternatives →

3. 3
   Fast.js – faster reimplementations of native JavaScript functions▲323

   Faster user-land reimplementations for several common builtin native JavaScript functions. - codemix/fast.js

   2014 · github.com · its alternatives →

4. 4
   Crowdsourced freelance contract template, written in plain language▲299

   Freelance contract template written in plain language. Compatible with Google Docs or Microsoft Word. Perfect for graphic designers, web developers, bloggers and more.

   2019 · web.archive.org · its alternatives →

5. 5
   VanillaList▲218

   Handpicked Vanilla JavaScript plugins repository

   2022 · vanillalist.top · its alternatives →

6. 6
   6to5 – Turn ES6 code into vanilla ES5 with source maps and no runtime▲48

   🐠 Babel is a compiler for writing next generation JavaScript. - babel/babel

   2014 · github.com · its alternatives →

7. 7
   Diagram as code tool with draggable customizations▲266

   In the past I've used declarative diagram generation tools like Mermaid.js a lot for quickly drawing up things but for presentations or deliverables I find that I have to then move the generated diagrams over to a tool like Lucidchart which allows full control of the organization and customization. Therefore I am now working on this to combine the benefits of both into just one tool which can do both functions. The project is certainly in the early stages but if you find yourself making architecture diagrams I'd love to hear your thoughts on the idea or even a Github issue for a feature…

   Oct 2025 · github.com · its alternatives →

8. 8
   Kneden – Transpile ES7 Async/await to ES6 Promise Chains (Babel Plugin)▲76

   Transpile ES2017 async/await to vanilla ES6 Promise chains: a Babel plugin - babel/kneden

   2016 · github.com · its alternatives →

9. 9
   Faster.js – a micro-optimizing JavaScript compiler▲89

   faster.js is a Babel plugin that compiles idiomatic Javascript to faster, micro-optimized Javascript. - vzhou842/faster.js

   2018 · github.com · its alternatives →

10. 10
    JavaScript-first, open-source WYSIWYG DOCX editor▲130

    We needed a JS-first WYSIWYG DOCX editor and couldn't find a solid OSS option, most were either commercial or abandoned. As an experiment, we gave Claude Code the OOXML spec, a concrete editor architecture, and a Playwright-based test suite. The agent iterated in a (Ralph) loop over a few nights and produced a working editor from scratch. Core text editing works today. Tables and images are functional but still incomplete. MIT licensed.

    Feb 2026 · github.com · its alternatives →

11. 11
    Codewich – A live-updating TypeScript/CSS/HTML playground▲114

    Create and share simple web demos using TypeScript, CSS, and HTML. Prototype new ideas quickly.

    2017 · codewich.com · its alternatives →

12. 12
    GRPHC Contracts▲75

    Generate design contracts for clients

    2021 · its alternatives →

13. 13RJ
    Rune.js – Graphic design systems with SVG in the browser or Node.js▲92

    A JavaScript library for programming graphic design systems with SVG

    2015 · runemadsen.github.io · its alternatives →

14. 14
    Stately Studio 1.0▲108

    Design flows visually, collaborate, export to code

    2022 · stately.ai · its alternatives →

15. 15JA
    JavaScript Application Design book▲66

    JavaScript Application Design: A Build First Approach [Bevacqua, Nicolas] on Amazon.com. *FREE* shipping on qualifying offers. JavaScript Application Design: A Build First Approach

    2015 · amazon.com · its alternatives →

16. 16
    DiagramJS – Create beautiful node diagrams using JavaScript▲33

    ☊ Tool for making node graphs. Inspired by dependency graph. Used mainly for automation services 📈 - aexol-studio/tree

    2018 · github.com · its alternatives →

17. 17
    Learn JavaScript Projects▲13

    Free JavaScript Projects & Figma Designs for Your Portfolio.

    2023 · learnjavascript.online · its alternatives →

18. 18
    CodeJS : An Actionscript 3.0-like syntax for Javascript▲6

    CodeJS | Class / Object Description Engine for JavaScript - neuromantic/CodeJS

    2011 · github.com · its alternatives →

19. 19
    Babel-plugin-istanbul for ES2015 test coverage▲5

    A babel plugin that adds istanbul instrumentation to ES6 code - istanbuljs/babel-plugin-istanbul

    2016 · github.com · its alternatives →

20. 20
    Typescript, Three.js, and JQuery 'Hello World' Example Project▲6

    A Typescript 'Hello World' example project that utilizes Three.js and jQuery through DefinitelyTyped typings. - selbyk/three.ts

    2016 · github.com · its alternatives →

21. 21
    Learn to code with JavaScript (French)▲11

    2015 · openclassrooms.com · its alternatives →

22. 22
    Scripting language inspired by JavaScript and GLSL▲29

    I'm working on a scripting-language heavily inspired by Javascript and GLSL. The idea is to use this for a game engine I'm working on.

    2022 · github.com · its alternatives →

23. 23
    Design by Contract (tm) – C++▲6

    Design by contract for C++. Includes inheritance capabilities. - RichardB01/dbc_cpp

    2020 · github.com · its alternatives →

24. 24
    JavaScript for Designers▲8

    Tired of being the "designer that doesn't know JavaScript"?

    2016 · betaflows.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 →