What can you do with 20 lines of JavaScript? These days, almost anything — which is why we want to see your best JS hack! It could be data processing, a CLI tool, maybe even some sort of crazy recursive algo. Whatever it is, you've got 20 lines to make it work.

Include your code (the submission form supports markdown) and explain what it does. Bonus points for screencasts & live demos.

The top winner will receive a 1 year GitHub Micro subscription and we'll award $50 ThinkGeek giftcards to the top 4 runners up.


Anyone 13 years of age or older can participate.


  • No teams - this is a solo competition
  • 20 lines or less of JavaScript, not including comments (and nothing else)
  • 80 characters per line max, including spaces
  • Use any previously existing & public API or libraries, but don't create one just to downsize your code, (you only have 20*80 characters total!)
  • no malicious code — pls don't hack the gibson

Hackathon Sponsors


$284 in prizes

Grand Prize

One year of Github (Micro personal plan at $7 / month)

Runners up (4)

$50 gift certificate at THINKGEEK

Devpost Achievements

Submitting to this hackathon could earn you:

How to enter

  1. Click “Register” to sign up.
  2. Create your hack with 20 lines (or less) of JavaScript (each line of code must be 80 characters or less) and nothing else
  3. Enter your submission by providing:
    • Your 20 lines of JavaScript in the description field (which supports markdown & fenced code blocks)
    • A description of how your hack works
    • At least one image of your code's output, if you have one, or something else (for the site gallery)
    • relevant tech & api tags (don't forget to add #20lines!)
    • (Optional) a link to a demo on codepen.io, jsfiddle.net, or another site


Neal Shyam
Community, ChallengePost

Stefano Ballabeni

Stefano Ballabeni
Developer, ChallengePost

Brandon Kessler

Brandon Kessler
Founder, ChallengePost

Ross Kaffenberger
Head of Engineering, ChallengePost

Judging Criteria

  • Does it work?
    Does your hack run as advertised and without errors for all our judges?
  • Creativity
    Is your hack just lipstick on an API, or did you create something really novel?
  • Elegance
    Ultimately, there's a million ways to make x=y, does yours exemplify the craft of coding?

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