Alternatives
Products that do what Extropy does
OSS engine that simulates population reacting to events
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Hi HN community! We want to share AI-town, a deployable starter kit for building and customizing your own version of AI simulation - a virtual town where AI characters live, chat and socialize. Inspired by great work from the Stanford Generative Agent paper (https://arxiv.org/abs/2304.03442). A few features: - Includes a convex.dev backed server-side game engine that handles global state - Multiplayer ready. Deployment ready - 100% Typescript - Easily customizable. You can fork it, change character memories, add new sprites/tiles and you have a custom AI simulation…
2023 · github.com
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2025 · attentionmech.github.io
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Simulate anything on a map from a text prompt -- and conduct risk analysis against LiveUA map's global realtime data points from social media and news sources. I trained a GPT-2-size model on historical incident data used to predict things that will go wrong. As historian Benjamin Breen mentions, the leading language models are good historians, so the application will simulate historical events pretty well also. I include a Multi-Agent RL Urban Mobility model in progress displayed on the map as small white cubes representing traffic and pedestrians. Around SF, it uses real census data and…
2025 · mused.com
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at a pub in london, 2 weeks ago - I asked myself, if you spawned agents into a world with blank neural networks and zero knowledge of human existence — no language, no economy, no social templates — what would they evolve on their own? would they develop language? would they reproduce? would they evolve as energy dependent systems? what would they even talk about? so i decided to make myself a god, and built WERLD - an open-ended artificial life sim, where the agent's evolve their own neural architecture. Werld drops 30 agents onto a graph with NEAT neural networks that evolve their own…
Feb 2026 · github.com
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Hey HN! The idea for this started when I came across the election forecast of FiveThirthyEight [1]. They show a 1000 different possible election outcomes - each one possible. In this newspaper homepage, I try to turn these simulations into reality by feeding AI with as much detailed information about a simulation as I can (e.g. voting results per state). See source code here [2]. The whole process is explained in more depth in my blog post: https://nerology.substack.com/p/how-i-made-the-probability-t... [1]…
2024 · theprobabilitytimes.com
- 13AB
I’ve been working on a browser-based evolutionary simulation as a personal experiment. Organisms adapt to environmental pressure over time, and there are no explicit goals or scoring, the system is open-ended and runs continuously. I built this mainly to challenge myself and to explore how to surface simulation behavior and statistics in a way that stays readable rather than overwhelming. As a side effect, it’s also something my kids enjoys watching run. Curious what resonates and what doesn’t, and happy to answer questions about the design or tradeoffs.
Jan 2026 · soupof.life
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Build autonomous Python agents with native Agent-to-Agent (A2A) communication - protolink/examples/ai_courtroom at main · nMaroulis/protolink
29d ago · github.com
- 15CB
This is a simulation that allows you to test how beliefs are adopted based on pre-existing beliefs and how they spread through a population. It is entirely editable, so you can test your own parameters based on your own data or intuitions. A detail methodology can be found here: https://www.lesswrong.com/posts/mj68CsoLDoCfTgeiw/methodolog...
2024 · nonzerosum.games
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2022 · thesciencegab.com
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Run realistic AI focus groups, get insights in minutes
Dec 2025 · artificialpopulations.com
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I built this simulator to study how simple trading agents interacting with an order book can create emergent patterns—volatility, clustering, even chaos—without any external shocks. It’s meant as both a research toy and teaching tool. You can run different strategies, adjust configs, and watch dynamics evolve. Curious to hear feedback from the HN crowd on features/dynamics you’d like to see added.
2025 · aitradingsim.com
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AgenticAI, Geopolitics, DefenseTech, Simulation, AI
Jul 2026 · macroops.tech
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I built an artificial life simulator that fits in one HTML file (~1400 lines ~50KB) with Claude Opus 4.6, interestingly, I didn't even ask it to build the game itself, I've requested to create the software that didn't exist before and not use any dependencies, third-party libraries or ask questions. Firstly Opus 4.6 made photoshop clone that barely worked, but had nice and neat UI with all common features for the image editor, then I've called that crap and asked to really build someting that wasn't there, it made Emergent there. Please check it out and tell what you think, of course it's a…
Feb 2026 · emergent-ivory.vercel.app
- 24EA
Hi HN! After a year of R&D at Inria (the French national lab), we have just open-sourced Ebiose. Ebiose is a distributed, Darwin-style playground where AI architect agents design, test, and improve other agents. Instead of AI built behind closed doors, anyone can spin up a forge, state a problem, and watch candidate agents compete until the fittest survive. An example instruction given to an Ebiose forge: "Build a LangGraph agent that processes SaaS customer refunds directly through our ERP, escalating to a human for edge cases. Use the following tools: ERP API, email/Twilio…
2025 · github.com
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