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nghiahsgs
nghiahsgs

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I built an open-source "focus group simulator" that spawns 1,000 AI customers to roast your startup idea

The Problem

Every founder has been there: you spend 3 months building something, launch it, and... crickets. Nobody wants it.

User interviews cost time. Landing page A/B tests cost money. Survey panels cost both.

What if you could get brutally honest feedback from 1,000 potential customers in 2 minutes?

What I Built

Sybil Swarm is an open-source swarm intelligence engine. You feed it your product URL or description, and it:

  1. Spawns 1,000 AI agents — each with a unique persona (age, job, income, personality, interests)
  2. Has them evaluate your product as real potential customers
  3. Generates a market prediction report with conversion rate, objections, and recommendations

The name comes from the Sibyls — prophetic oracles of ancient Greece.

Demo

The Dashboard

The simulation runs in real-time with:

  • Canvas world — agents move around, cluster by sentiment (buyers → right, rejectors → left)
  • Sentiment heatmap — fills up red/yellow/green as agents complete
  • Live feed — Twitter-like stream of agent reactions
  • Conversion funnel — Aware → Interested → Willing to Pay → Would Buy

## What the Report Looks Like

The AI synthesis agent writes a brutally honest market prediction:

  • Market Viability Score (0-100)
  • Conversion rate prediction
  • Top objections (what's killing your product)
  • Top suggestions (what would make people buy)
  • Go/No-Go recommendation

One of my test runs came back: "AgriBeacon is not viable in its current form. 0% conversion rate. Its value proposition is a
marketing mirage."
Ouch. But exactly what I needed to hear.

## Tech Stack

  • Backend: Python FastAPI, async parallel agent evaluation
  • Frontend: Next.js 16, Canvas 2D, Framer Motion
  • LLM: Any OpenAI-compatible API (works with free Alibaba Qwen tier)
  • No agent framework — just async batch LLM calls with semaphore. CrewAI/LangGraph are overkill for this.

## Try It


bash
  git clone https://github.com/nghiahsgs/Sybil-Swarm.git
  cd Sybil-Swarm
  # Set up your API key (Qwen free tier works!)
  cp .env.example .env
  # Install & run
  cd backend && pip install -e . && uvicorn app.main:app --port 8000 &
  cd ../frontend && npm install && npm run dev

  Open http://localhost:3000 → paste your URL → Launch Simulation

  Is This Actually Useful?

  Honestly? It's not a replacement for talking to real humans. But it's a cheap, fast pre-filter:

  - If 0% of simulated customers would buy → strong signal to pivot
  - If 40%+ would buy → worth investing in real validation
  - The objections list alone is worth it — things you didn't think of

  What's Next

  - Chat with individual agents post-simulation (already built)
  - More provider support (OpenAI, Anthropic, Google, Qwen)
  - Deploy as hosted service

  GitHub: https://github.com/nghiahsgs/Sybil-Swarm

  MIT license. Stars appreciated!

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Good