RePlay

What it does

Investing is learned through experience. Most beginners consume content but don't have a way to build judgment without risking real money. Replay AI displays real investment theses from specific points in time — including reasoning, assumptions, and key arguments. Users are placed in a moment in history, see only the information available then, and make a decision before seeing what the outcome would be, had you invested. This turns passive reading into active decision-making with feedback.

• 
  Portfolio Lab28d ago · portfoliolab.ai · ▲306

  AI investing, done responsibly

• 
  Aime by AInvest2023 · ▲258

  Your new AI financial advisor. Active Investing Made Easy.

• W3
  Watch 3 AIs compete in real-time stock trading2024 · trading.snagra.com · ▲270

  A live dashboard where you can watch GPT-4, Claude 3, and Gemini analyze market data and make daily stock trades with real money. Each AI explains its reasoning, and you can compare their different approaches to the same data. Link: https://trading.snagra.com?utm_source=hn (no signup required) What you can try right now: - Watch live trades from GPT-4, Claude 3, and Gemini - Read each AI's full analysis and reasoning - Compare their different interpretations of the same market data - Track their real-time performance and win rates - View historical trades and performance metrics…

• 
  MyInvestment-AI2024 · ▲130

  AI helps secure wealth, trusted by 300+ users

• 
  Real Estate Investing Simulator (Beta)2024 · ▲119

  Learn real estate investing in a fun zero risk way

• 
  EquityReplay8d ago · equityreplay.com · ▲2

  Explore public portfolios, build an AI mix, replay history.

• 
  PaymentKit▲466

  Billing that survives a processor shutdown

  Commerce · 14d ago · paymentkit.com

• 
  Equitybee Benchmark▲241

  Compare your startup equity grant for free.

  Commerce · 27d ago · equitybee.com

• 
  Brila▲1,367

  One-page websites from real Google Maps reviews

  AI · Apr 2026 · brila.ai

• AG
  A game where you build a GPU▲964

  Thought the resources for GPU arch were lacking, so here we are

  Life & fun · Apr 2026 · jaso1024.com

• IB
  I built a tiny LLM to demystify how language models work▲915

  Built a ~9M param LLM from scratch to understand how they actually work. Vanilla transformer, 60K synthetic conversations, ~130 lines of PyTorch. Trains in 5 min on a free Colab T4. The fish thinks the meaning of life is food. Fork it and swap the personality for your own character.

  AI · Apr 2026 · github.com

• 
  Fathom 3.0▲803

  AI meeting notes: now bot-free, in ChatGPT & Claude + more

  AI · Apr 2026 · fathom.ai

• BC
  Brutalist Concrete Laptop Stand (2024)▲786

  Life & fun · Apr 2026 · sam-burns.com

• IB
  I built a frontpage for personal blogs▲783

  With social media and now AI, its important to keep the indie web alive. There are many people who write frequently. Blogosphere tries to highlight them by fetching the recent posts from personal blogs across many categories. There are two versions: Minimal (HN-inspired, fast, static): https://text.blogosphere.app/ Non-minimal: https://blogosphere.app/ If you don't find your blog (or your favorite ones), please add them. I will review and approve it.

  AI · Apr 2026 · text.blogosphere.app