# VibeGame: Exploring Vibe Coding Games

[Hugging Face](https://yomu.fyi/company/hugging-face) · Dylan Ebert · Sep 29, 2025

**Type:** Problem & solution

## Summary

Vibe coding games often fails as projects grow because large context sizes degrade model performance. After evaluating Roblox MCP, Unity MCP, and open web libraries with Claude Code, the author found web tooling offered the strongest model proficiency but lacked high-level game abstractions. To bridge this gap, the author created VibeGame, an open-source declarative game engine built on three.js, rapier, and bitecs. VibeGame uses an Entity-Component-System architecture, XML-like markup, and bundled documentation in an llms.txt file to keep project context lean. While effective for basic physics and rendering mechanics, the engine requires further development for complex features like inventories, multiplayer, and interactions.

## Context

AI-assisted game development struggles as project size grows because expanding context windows degrade model performance, and existing platforms present trade-offs between high abstraction and poor context management.

## Approach / What changed

Built Shallot for context management in Claude Code and created VibeGame, a declarative, open-source web engine using three.js, rapier, and bitecs with an Entity-Component-System architecture and AI-targeted documentation.

## Takeaways

- Roblox MCP provides strong high-level abstractions but restricts context management, while Unity MCP suffers from high API variability that confuses models.
- Web technologies like three.js and bitecs yield superior model code generation due to extensive training data, but they lack built-in high-level game abstractions.
- VibeGame bundles an llms.txt documentation file to provide direct engine context for tools like Claude Code and other large language models.

**Tags:** [Architecture](https://yomu.fyi/topic/architecture), [Developer Experience](https://yomu.fyi/topic/developer-experience), [LLMs](https://yomu.fyi/topic/llm), [Open Source](https://yomu.fyi/topic/open-source)

[Read original post](https://huggingface.co/blog/vibegame)