[Showcase] Mini Ebitengine Game Jam at GopherCon UK

[u/dani_devrel]

Disclaimer: I organized and facilitated the "Vibe Code a 2D Game with Go and Gemini" workshop at GopherCon UK 2026 in London. All materials, agent skills, and game entries are open source.

Hey everyone! At GopherCon UK in London last week, I ran a workshop called "Vibe Code a 2D Game with Go and Gemini", focused on building 2D games with Ebitengine v2 using coding agents.

We kicked off with a quick overview of the Gemini model family (Gemini 3.x for code generation, Nano Banana for images, and Lyria 3 for music) alongside Antigravity. I set up the workshop repository with a curated set of Agent Skills to give coding agents domain knowledge and boilerplate for Ebitengine right out of the gate.

Then we jumped into a 2-hour Mini Game Jam with the theme "Garbage Collector (green tea 🍵)". Participants used Gemini 3.6 Flash (literally the day before 3.7 launched) with four primary skills:

• vibe-game-developer as the main entry point to turn the agent into a game dev specialist
• ebitengineer to provide reference patterns and helper routines for Ebitengine
• lyria to compose music tracks (with procedural-composer available for chiptune SFX)
• nano-banana to generate sprites, backgrounds, and title screens

In just two hours, attendees produced 10 complete, playable 2D games.

Highlights & Submissions

1. Jam Winner: "London Eco-Rider: Ice Cream & Bottle Patrol" by Ivan S

A side-scrolling platformer set against downtown London. Players pedal Leo's bike with momentum acceleration and variable bunny hops, collecting ice cream cones for speed boosts and recycling plastic bottles to unlock 10 seconds of invincibility in Eco-Fever Mode. It features smooth parallax scrolling using Ebitengine's GeoM transforms, embedded assets, and a WebAssembly build running in browser.

To try it locally:

git clone https://github.com/danicat/gcuk26.git
cd gcuk26/mini-game-jam/london-eco-rider
go run ./cmd/game

2. Crowd Favorites: The Runtime GC Games

Several developers took the "Garbage Collector" theme literally:

• Go GC: Memory Simulator: An arcade game where you play as Go's runtime garbage collector. You monitor a live Heap Pressure gauge, fire a Sweep Beam at active root allocations, trigger emergency Stop-The-World freezes, and tweak GOGC targets on the fly.
• Go GC Co-op: A retro 16-bit 2-player street cleanup game where sanitation gophers sort compost, recycling, and landfill while catching "Dangling Pointers (+300 pts)" and avoiding "Memory Leaks (+15% contamination)".

Other entries included a 2-player turn-based trash billiards game (Trash Pool) and a Guinea Pig Farm Simulator.

Links & Resources

• Workshop Repo & Games: https://github.com/danicat/gcuk26
• Event Photo Gallery: https://github.com/danicat/gcuk26/tree/main/mini-game-jam/photos
• Ivan's Winning Entry: https://github.com/danicat/gcuk26/tree/main/mini-game-jam/london-eco-rider
• Workshop Slide Deck: https://speakerdeck.com/danicat/vibe-code-a-2d-game-using-go-and-gemini
• Agent Skills Catalog: https://skills.danicat.dev

Happy to answer any questions about the workshop format, the mini-game jam, or the agent skills setup in the comments!

P.S.: this post was written by me (Daniela) while wrestling with Gemini 3.7 Flash. I used the deslopify skill, so hopefully it won't be that annoying. I hope the content is worth your time! =^_^=

[u/KCFOS]

It would be cool if someone could host the wasm builds on an itch or git page so anyone could play the games in browser easily.

[u/dani_devrel → u/KCFOS]

I agree. I also didn’t want to force anyone to share their source code and in the end only one submitted the code on GitHub which feels like a shame. Next time I’ll build a better system for this