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LeoTheAIDev
LeoTheAIDev

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I Built AltiVerse: Fork Any Decision Into Living Simulations With 1,000 Personalities

I Built AltiVerse: Fork Any Decision Into Living Simulations With 1,000 Personalities

What if you could see the real human consequences of a decision before making it?

Not through abstract models or spreadsheets — but by watching living simulations of people reacting, interacting, and slowly pulling realities apart.

That's what AltiVerse is.

The Problem

We constantly make decisions with massive second-order effects:

  • Should we ban phones in schools?
  • Is a 4-day work week actually better?
  • Are 8-hour or 12-hour hospital shifts healthier in the long run?

Traditional tools fail here. They can't capture how real humans with emotions, relationships, and memories behave over time.

What AltiVerse Does

AltiVerse lets you:

  • Pick any decision and fork it into 2–4 alternate realities
  • Run each as a deterministic living simulation with up to 1,000 agents
  • Each agent has personalities, moods, memories, and relationships
  • Watch people move through rooms, talk, form groups, and evolve
  • See exactly when and why the timelines diverge
  • Click any person to compare their entire life across realities
  • Export a full report with in-character thoughts and recommendations

Everything is fully deterministic — same seed = same world every time. Optional LLM layer only for readable prose.

Example: School Phone Ban

I forked a strict phone ban into 4 slightly different implementations.

  • In one timeline: Academic performance improved significantly
  • In another: Students became more isolated and anxiety spiked
  • In a third: Rebellion culture emerged by week 6

The divergence was visible and fascinating.

Technical Highlights

  • Deterministic simulation engine
  • Room-based spatial movement and interaction system
  • Individual agent memory and relationship modeling
  • Timeline comparison UI
  • Report generation with optional LLM enhancement

The project is completely open source.

Try It Yourself

GitHub logo LeoTheAIDev / Altiverse

Fork decisions into living simulations with 1,000 personalities. Watch alternate realities diverge and explore second-order effects.

AltiVerse — fork a decision. Watch the worlds it creates.

Take one choice. Play it forward as several alternate realities — each a small living world of people who move, stress out, break rules, burn out, form friendships and rivalries, and tell you how it felt.

License: MIT Local-first Vite Runs offline Node



What is AltiVerse?

AltiVerse forks a single decision — a school phone ban, a 4-day week, 8- vs 12-hour hospital shifts — into 2–4 alternate realities and runs each one forward as a small, living simulation. Up to ~1,000 people with personalities, moods, and relationships move through rooms, react to the policy, and slowly pull the worlds apart. You watch when and why the realities diverge, click any person to compare how they fare across timelines, and export a full report with a recommendation.

It is a thinking tool, not a predictor. Every number and quote comes from a deterministic engine (same seed → same world, every time), with an optional local or online…






Quick start instructions are in the README.

What’s Next?

I’m actively improving:

  • Performance and scaling (aiming for more agents)
  • Richer personality and relationship systems
  • Better visualization tools
  • More example scenarios

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