Stay updated on https://bsky.app/profile/gbdev.io

Create original games, demos, homebrews tools and music for the original Game Boy / Game Boy Color and compete for fame, glory and over $5000 of prizes!

Join us on Discord to get started with Game Boy development, find a team or get help!

More details (and the full ruleset) can be found at gbdev.io/gbcompo25.

---

The total cash prize pool of will be split according to this document. Anybody can contribute by donating or joining as a sponsor.

Additionally, there are also physical prizes, including:

• The sold out first edition Modretro Chromatic
• Various Modretro games on cartridge
• The ModRetro X Koss Porta Pro

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

• The entry must implement/interpret the jam theme (applies to Game category only).
• The final deliverable must consist of a GB or GBC ROM file.
• GBC features are allowed (entries may be GBC only)
• SGB features are allowed (but don't rely on them)
• You can use RGBDS (ASM), GBDK (C), ZGB (C), GB Studio, GBSDK(C+RGBDS ASM) or anything that produces a valid ROM.

• Jam Theme: None (there is no theme, do whatever you want!)

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)
  • Pre-made and AI generated assets for art and music are ok if the licensing permits. Make note of what is being used/reused and under what terms. It may be factored in when judging entries.
• 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

An entry can compete in one and only one of the following leaderboards:

• Games
  • The best 5 games will get a prize.
  • The best 3 OSS games will get an additional prize (can overlap)
  • Examples: Hermano, Feed IT Souls, Enceladus
• Music cartridges (1 prize)
  • Examples: 8bit Sunset, Tune In!
• Demoscene style (1 prize)
  • This category is for audio-visual demonstrations that run without viewer interaction, in such a way as to demonstrate skill in manipulation of the Game Boy hardware through code, special effects, art, music, and direction. More on Wikipedia.
  • Examples: Back to Color, Is that a demo in your pocket?, Cute Demo CGB.
• Tool (1 prize)
  • Examples: Monster Orc-arina, On-Board GB Tile Creator, Witch Sound Tracker.

Here is a curated list of tools and documentation to get you started.

• General links
  • The Game Boy, a hardware autopsy (Video)
  • The Ultimate Game Boy Talk (Video)
  • Pan Docs, Game Boy technical documentation
  • Awesome Game Boy Development list of resources
    • Especially relevant is the "Software Development" section
  • How to choose between C and ASM for GB?
• RGBDS (ASM language)
  • GB ASM Tutorial
• GBDK (C language)
  • API docs: Getting Started
  • Examples / Open Source GBDK games
  • Docs, links and tools
  • ZGB: a game engine using GBDK / CrossZGB (an updated fork of ZGB)
  • Dedicated Discord
  • "How-to make a Gameboy Game" tutorial series
• GBStudio (no coding required)
  • Resources to get started
  • Dedicated Discord
  • Let's Build a Platformer Game!
    
• GBSDK (C + RGBDS ASM, without a standard library)
  • Documentation
  • Source for a game and another game built with GBSDK

• Music
  • lsdpack and lsdlack-kit for making LSDJ playback ROMs
    (other audio drivers in ROM form are ok too)

Past editions

  

Check out gbcompo21 and gbcompo23, the past editions of the event, to get inspired and see the winning entries. Some of them were also released as Open Source!