Everyone is talking about building a "second brain" with AI, but most people misunderstand what it actually is. In this session I break down the truth: a second brain is 100% about your knowledge and 0% about which AI you use. I show you the second brain I built, explain the LLM Wiki concept created by Andrej Karpathy, and walk through the three levels of building one, from simple keyword links to embeddings and full document sectioning. By the end you will know exactly how to turn your scattered notes, emails, transcripts and CRM data into something you can actually talk to. ⏱️ TIMESTAMPS: 0:00 Welcome & who is Miguel 1:34 What a "second brain" really is 2:58 The LLM Wiki (Andrej Karpathy's approach) 5:37 Building the index of connections 7:03 Live walkthrough of my second brain 8:39 Aside: design systems & getdesign.md 11:05 The 3 levels — Level 1: keyword links 14:44 Level 2: embeddings (meaning, not just words) 19:05 Level 3: document sectioning 20:30 Resources, my website & the API pricing dashboard 23:07 Q&A: do you still need RAG? 25:23 Closing 🔗 CONNECT WITH ME: 💼 LinkedIn: https://www.linkedin.com/in/miguel-torrez/ 🌐 Genial Agency: https://genial-agency.com 🇫🇷 Luwai (French): https://luwai.fr 👤 Personal: https://migueltorrez.ai 📅 Book a chat: https://cal.com/miguel-torrez 🛠️ TOOLS MENTIONED: • Claude (Claude Code): https://claude.ai • Codex: https://chatgpt.com/codex • ChatGPT: https://openai.com • Perplexity: https://plex.it/referrals/L3JAI8VO • Google Gemini: https://gemini.google.com • Antigravity: https://antigravity.google • Figma: https://www.figma.com/ • Design systems reference (getdesign.md): https://getdesign.md/ 💬 LIVE CHAT HIGHLIGHTS: [8:39] @Trang Nguyen: "I struggle to set up a good design system. I feed it brand guidelines, front-end code base, screenshots... but the design is still off on colour, size and spacing. How do I fix it?" [12:56] @Trang Nguyen: "The index seems like something useful for RAG and setting up agents." 💬 DROP A COMMENT: Have you built your own AI second brain yet? What knowledge would you connect first — your emails, your notes, or your CRM? #AI #SecondBrain #LLM #KnowledgeManagement #ClaudeCode #ArtificialIntelligence #AIforBusiness #Embeddings #RAG #Productivity