Every time I used ChatGPT or similar tools the same thought crossed my mind: "Where is this conversation going? Who has access to it? What are they doing with my data?" So I decided to build my own solution. Meet CrustAI 🦀 — a fully private, self-hosted AI assistant that runs entirely on your own machine. No cloud. No subscriptions. No data leaving your computer. Ever. 🌐 Documentation | ⭐ GitHub Most AI assistants have one fundamental issue — your data belongs to someone else. When you ask ChatGPT something personal, that conversation is: Stored on OpenAI's servers Potentially used to train future models Subject to their privacy policy (which can change) Accessible in case of a data breach I wanted an AI assistant that was genuinely mine — one that I could use daily through apps I already use (Telegram, WhatsApp) without worrying about privacy. CrustAI is a self-hosted AI assistant powered by Ollama that connects to your favorite messaging platforms and runs completely offline after setup. 🔒 100% Private — all processing happens on your hardware 🧠 Local LLM — powered by Ollama (llama3.2, tinyllama, phi3, mistral...) 📱 Multi-platform — Telegram, WhatsApp, Discord and Slack 🧬 Long-term memory — remembers facts across conversations 🗣️ Offline voice — speech-to-text and text-to-speech (pt-BR) ⚡ REST API — built-in Fastify server for custom integrations 🎭 Custom personality — fully configurable assistant behavior Technology Purpose Node.js Runtime environment Ollama Local LLM inference engine node-telegram-bot-api Telegram integration @whiskeysockets/baileys WhatsApp integration discord.js Discord integration @slack/bolt Slack integration Fastify REST API server sql.js Embedded SQLite for memory yaml Configuration management The architecture is straightforward — a central message handler receives messages from any platform and routes them through the same pipeline: ┌─────────────────────────────────────────────────────┐ │ CrustAI Core │ │ │ │ ┌──────────┐ ┌──────────┐ ┌──────────────────┐ │ │ │ Telegram │ │ Discord │ │ WhatsApp │ │ │ │ Adapter │ │ Adapter │ │ Adapter │ │ │ └────┬─────┘ └────┬─────┘ └────────┬─────────┘ │ │ └──────────────┼──────────────────┘ │ │ ▼ │ │ ┌─────────────────┐ │ │ │ Message Handler │ │ │ └────────┬────────┘ │ │ ┌───────────┼───────────┐ │ │ ▼ ▼ ▼ │ │ ┌─────────┐ ┌────────┐ ┌──────────┐ │ │ │ Ollama │ │ Memory │ │ REST API │ │ │ │ (LLM) │ │ Store │ │ Server │ │ │ └─────────┘ └────────┘ └──────────┘ │ └─────────────────────────────────────────────────────┘ Each platform adapter is independent — you enable only what you need in config.yml. Node.js ≥ 20 Ollama installed A Telegram bot token from @BotFather Step 1 — Clone the repository git clone https://github.com/DaveSimoes/CrustAI.git cd CrustAI npm install # Start the Ollama server (keep this terminal open) ollama serve # In a new terminal — pull a lightweight model ollama pull tinyllama # 600MB — works on modest hardware # or ollama pull llama3.2 # 2GB — needs ~8GB RAM cp config/config.example.yml config/config.yml Edit config/config.yml: model: tinyllama ollama_url: http://localhost:11434 language: pt-BR telegram: enabled: true token: YOUR_BOT_TOKEN_HERE allowed_user_ids: [] npm start Expected output: ✓ Ollama connected (tinyllama) ✓ Memory store ready (./data/memory.db) ✓ Telegram ready ✓ REST API ready (http://localhost:3000) 🦀 CrustAI is ready. Your shell awaits. Once running, use these commands directly in Telegram (or any connected platform): Command Description /ping Check if the bot is alive /help Show all commands /model Show which AI model is running /remember Store a fact in long-term memory /forget Erase all stored facts /clear Clear conversation history CrustAI was built with privacy as its core principle, not an afterthought: ✅ All conversations processed locally — nothing leaves your hardware One concern I had was performance. I'm running CrustAI with tinyllama on a machine with limited RAM and it handles daily conversations well. For basic Q&A and conversation, tinyllama is surprisingly capable. If you have more resources, llama3.2 or phi3 give significantly better results. [ ] Web UI dashboard [ ] Image understanding (multimodal LLMs) [ ] Plugin system for custom tools [ ] Docker one-click deployment [ ] Mobile app companion CrustAI is open source and I'd love contributions from the community: 🐛 Bug reports — open an issue 💡 Feature ideas — let's discuss in issues 🔧 Pull requests — always welcome ⭐ Star the repo — helps others discover it! GitHub: https://github.com/DaveSimoes/CrustAI Documentation: https://documentcrustai.netlify.app Building CrustAI taught me a lot about local LLM inference, multi-platform bot development, and the real meaning of privacy-first software. If you're tired of sending your conversations to the cloud, give CrustAI a try. Your data deserves to stay yours. Made with 🦀 and ❤️ by Dave Simoes If you found this useful, consider starring the repo and sharing with others who care about privacy!