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forkphorus runs Scratch 3, 2, and 1 projects really fast by compiling them to JavaScript. Try it out by pasting a project ID or URL into the field below, selecting a project file, dropping a file on the page, or exploring the examples studio.

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forkphorus is a based on Nathan's phosphorus. Its CPS-style compilation and overall design was inspired by Rhys's sb2.js. It would have more bugs if not for Truman and Tim. The JSZip library is used to read .sb2 and .sb3 files, and the canvg library is used to render SVGs in <canvas> elements for some projects.


The source code for forkphorus is available on GitHub.

Version 96b5d33, updated 2020-07-10