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JS "intro" Packer
Ruby JavaScript HTML
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JS "intro" Packer

JSIP takes any piece of "JavaScript" and packs into a 100% valid PNG image file, which is then "loaded" and "decoded" at run-time.

Unlike other similar "packers", it doesn't not rely on any custom PNG chunks or other "hacks", as a result you can expect the actual "compressed" size to be slightly larger than usual.

Wasting a few bytes, for better compatibility, is totally acceptable.

Please keep in mind, that even with the indirect "eval", there's quite a significant performance hit on the "evaluated" code.

Be sure to test the "result" in multiple browsers.


./jsip.rb 2k.js > 2k.html


ruby jsip.rb 2k.js > 2k.html

or as a "library"

require 'jsip''hello_world.html', 'w') do |f|
  f.write(JSIP::HTML.format('hello world','alert("hello world");'))))


  • Fork the project.
  • Make your feature addition or bug fix.
  • Do not bump the version number.
  • Send me a pull request. Bonus points for topic branches.


Released into the Public Domain. No warranty implied. Use at your own risk.

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