Solo Dev Builds 3D Multiplayer Browser Game in a Weekend with Opus 5
yerbamate2020 · reddit · 2026-07-30
A developer with no prior game dev experience used Opus 5 (High mode) over a weekend to build a high-fidelity 3D multiplayer browser game inspired by CoD Zombies. It features full physics interactions, 3D models, and a global leaderboard, hitting 1,000+ sessions in 4 days.
Key Engineering Takeaways:
- Stop chasing the one-shot: The initial working version looked like a cheap Roblox knockoff. It took 119 commits and rigorous iteration to reach a playable state.
- Play it yourself constantly: AI lacks human visual intuition. Developers need to playtest and provide raw feedback (e.g., "this looks fucked up" + screenshot), which Claude effectively translates into physics tweaks.
- Always add "and everywhere else": When reporting a bug, explicitly tell the AI to fix it globally. Otherwise, it will only patch the specific instance, causing recurring issues later.
Related event: Developers Build and Fix 3D Web Games Using Opus 5(2 posts)→
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