This jam is now over. It ran from 2021-07-01 00:00:00 to 2021-10-01 00:00:00. View 137 entries

This jam is done!

Check out the winners at : gbdev.io


Create original games, demos, homebrews tools and music for the original Game Boy / Game Boy Color and compete for glory (and a lot of prizes)!

Current prize pool: $3000+ (details)

Head over https://gbdev.io/gbcompo21 for the complete rule set, details and resources to get started!



This competition is about making software that can run on actual game boy hardware.

  • The final deliverable must consist of a GB or GBC ROM file.
  • GBC features are allowed
  • SGB features are allowed (but don't rely on them)
  • You can use RGBDS (ASM), GBDK (C), ZGB (C), GB Studio, or anything that produces a valid ROM.

Incube 8 Games

Greenboy Games Catskull Electronics Mega Cat Studios Bitmap Soft 1st Press Games

Individual Sponsors

ToxaCarles CastilloDave VanEeChris MaltbyWilliam Bettridge-RadfordJosh FrisbySanqui


Entries will compete in 4 separate categories:

  • Best game - (5 awarded and additional open source bonus for the top 3)
  • Best homebrew / tool - (1 awarded, running on a GB/GBC)
  • Best music cartridge - (1 awarded)
  • Best demoscene style demo - (1 awarded)


See the github page for complete details and rules.

Your work must be new and original:

  • Examples of things that are allowed:
    • A brand new game using your own (or any) existing game engine
    • A remake of your (or someone else's) game for a different platform, but with new code and assets
    • A brand new game you barely started (e.g. you only made a title screen or a mockup of the gameplay)
    • Asset packs for art and music are ok if the licensing permits. Make note of what is being reused and under what terms
  • Examples of things that are not allowed:
    • A project you've been working on for months
    • An update/patch for a game you already released publicly
    • ROM Hacks
    • NSFW content