jsonplaceholder - A simple online fake REST API server

•    Javascript

JSONPlaceholder is a simple fake REST API for testing and prototyping.It's like an image placeholder but for web developers.

Framer - Framer - Design Everything

•    Javascript

Framer Library is an open source JavaScript framework for high fidelity prototyping. Use it to design animations and interactions without any limitations. Make use of real spring physics or animate with 3D effects, anything is possible. There are 2 ways to use Framer Library. To get most out of Library download Framer; a design tool for the Mac. The other way you can leverage Framer Library is with generator; an app that imports your layers from Sketch, Photoshop and Figma. The following features are included with each option.

TestDrive - Quickly try out any Swift pod or framework in a playground

•    Swift

Quickly try out any Swift pod or framework in a playground

IBAnimatable - Design and prototype customized UI, interaction, navigation, transition and animation for App Store ready Apps in Interface Builder with IBAnimatable

•    Swift

Design and prototype customized UI, interaction, navigation, transition and animation for App Store ready Apps in Interface Builder with IBAnimatable. Here is the full design in a Storyboard in Interface Builder.

pencil - The Pencil Project's unique mission is to build a free and opensource tool for making diagrams and GUI prototyping that everyone can use

•    Javascript

Only OSX 64bit 10.9 and later are supported. Windows 7 and later are supported, older operating systems are not supported (and do not work).

vuegg - :hatching_chick: vue GUI generator

•    Javascript

Scaffold vuejs projects by dragging-dropping components directly into the visual editor and moving-resizing them to your choice. Vuegg leverages the creation of the pages and routes of your app/website, eases the styling work and helps to achieve a rapid-prototyping workflow (... at least in theory). The aim of this project is to merge designing and prototyping into one single process. Whenever you're happy with what you see on the screen, just get your code.

x0 - Document & develop React components without breaking a sweat

•    Javascript

Read more about x0 in our blog post. x0 renders a directory of React components, automatically handling routing based on filename. Create a docs folder and add an index.js file.

wired-elements - Collection of elements that appear hand drawn. Great for wireframes.

•    Javascript

Wired Elements is a series of basic UI Elements that have a hand drawn look. These can be used for wireframes, mockups, or just the fun hand-drawn look. The elements are drawn with enough randomness that no two renderings will be exactly the same - just like two separate hand drawn shapes.

wired-elements - Collection of custom elements that appear hand drawn

•    TypeScript

Wired Elements is a series of basic UI Elements that have a hand drawn look. These can be used for wireframes, mockups, or just the fun hand-drawn look. The package (wired-elements) exports all components in the wired category. List of all wired elements can be found here.

atmo - :heavy_check_mark: Mock data for your prototypes and demos. Remote deployments to Zeit now.

•    TypeScript

Atmo makes creating mock web services for demos, presentations and experiments ridiculously easy.You are looking at the new Atmo, which is an electron app. But the initial version was a CLI tool. Find atmo classic here.

ok-mdx - Browser-based MDX editor

•    Javascript

MDX is great for documentation, building demos, or quickly prototyping with React components, without the need to set up a full-blown React application. Similar to Compositor x0, ok-mdx is meant to be installed as a global command line utility that you can use alongside your application setup or in isolated sandbox environments. ok-mdx works well as a local alternative to tools like CodeSandbox when working with React components. ok-mdx needs a directory of .mdx or .md files to work.

json-server - Get a full fake REST API with zero coding in less than 30 seconds

•    Javascript

JSON Server is a full fake REST API with zero coding in less than 30 seconds Created with <3 for front-end developers who need a quick back-end for prototyping and mocking.

mmock - Mmock is an HTTP mocking application for testing and fast prototyping

•    Go

Easy and fast HTTP mock server. Built with Go - Mmock runs without installation on multiple platforms.

Rosetta.NET

•    DotNet

Rosetta is tool for building all kinds of tasks without having to program a single line of code.

SketchFlow Template for Windows Phone

The SketchFlow Template for Windows Phone adds a new SketchFlow template for Expression Blend users, making it fast and easy to prototype Windows Phone applications.

PTE

•    ASPNET

Using template Excel to generate UI for Prototyping.

.NET Gadgeteer Projects from Digital Interaction

Digital Interaction Group develops Microsoft .NET Gadgeteer modules, code and example projects.

Interaction Production Server (ThorDMX)

A software based networked lighting controller. It brokers many protocols together to allow easy setup and development of new stage lighting controllers.

laravel-sketchpad - An innovative front-end environment for interactive Laravel development

•    PHP

Sketchpad is an innovative, bolt-on development environment for your existing Laravel site. It's a place to write, test, experiment and execute code, or just a place to group useful tools and functions you want easy access to.

paper-gui - A clone of dat.GUI using nice Polymer paper elements.

•    HTML

A clone of dat.GUI using Polymer: similar API but with Material Design UI and touch/mobile friendly.