I built an online multiplayer game (a MUD) in 1992 when I was 19. It ran on CompuServe, won Computer Gaming World’s 1993 award for artistic excellence, and shut down on Y2K eve. No source code survived. All I had left: Game Master scripts written in a custom scripting language I designed in the '90s, a gameplay capture from 1996, a GM manual from 1998, and some player docs. I pointed Claude Code at these artifacts and basically said “figure this out.” Here’s what it did: Reverse-engineered my scripting language : case-insensitive, DOS-encoded, implicit block termination, no formal spec anywhere. It parsed the GM manual and example scripts and reconstructed the full grammar. Rebuilt the entire game engine from scratch : Go backend with goroutines for multiplayer concurrency, React/TypeScript frontend, WebSocket connections, MongoDB persistence. Reconstructed the game world : 2,273 rooms, 1,990 items, 297 monster types, 88 spells across five magic schools, 30 psionic disciplines, 8 playable races, a full crafting pipeline (mining → smelting → forging, alchemy, weaving), d100 combat with damage severity tiers, stance modifiers, fatigue, weather effects. The part that genuinely surprised me: a language I designed three decades ago, with no formal specification beyond a GM manual and a pile of example scripts, was fully reconstructed by an AI agent that had never seen it before. This was a weekend project. The original took months of solo C programming in the '90s. The game is live and free to play at lofp.metavert.io . Code is MIT-licensed on GitHub . There’s also a bot API so AI agents can play the game alongside humans: same rules, same world. Expanded technical writeup here if you want the deep dive on how the agentic coding session actually worked: https://meditations.metavert.io/p/resurrecting-a-1992-mud-with-agentic submitted by /u/jradoff
Originally posted by u/jradoff on r/ClaudeCode