The latest articles on DEV Community by Lukasz (@quashudev). https://dev.to/quashudev https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3969992%2F536aa816-a6dc-48d4-9933-607d818f4476.png https://dev.to/quashudev en Lukasz Fri, 05 Jun 2026 14:51:07 +0000 https://dev.to/quashudev/i-built-a-content-tool-where-the-ai-runs-100-in-the-browser-no-servers-no-api-keys-8ed https://dev.to/quashudev/i-built-a-content-tool-where-the-ai-runs-100-in-the-browser-no-servers-no-api-keys-8ed <p>Most "AI content" tools send everything you write to a server. I didn't want that — so I built <a href="https://24-u.vercel.app/landing" rel="noopener noreferrer">24U</a> to run the model <strong>entirely in the browser</strong>.</p> <h2> The idea </h2> <p>Paste one article, note, or voice memo → get 11 platform-native posts (LinkedIn, Instagram, TikTok, X, Reddit, YouTube, Threads, Pinterest, Telegram, WhatsApp, Facebook). Each written for that platform's style, not copy-paste.</p> <p>The twist: <strong>nothing you write ever leaves your device.</strong></p> <h2> How it runs locally </h2> <ul> <li> <strong>WebLLM + WebGPU</strong> load a quantized LLM into the browser. After a one-time ~2GB download it runs offline.</li> <li>No backend inference, no API keys, no per-token cost — the "server" is the user's own GPU.</li> <li> <code>COOP</code>/<code>COEP</code> headers enable <code>SharedArrayBuffer</code> (required for the WASM/WebGPU runtime).</li> <li>ONNX/native deps are kept out of the server bundle so the Next.js function stays tiny.</li> </ul> <h2> Tradeoffs (honest) </h2> <ul> <li>Needs a WebGPU browser — Chrome/Edge today, Safari/Firefox are WIP.</li> <li>That one-time 2GB download is the price of full privacy + offline use.</li> <li>A small in-browser model isn't GPT-4 — but for "rewrite this for platform X" it's more than enough, and it never sees a server.</li> </ul> <h2> Why one-time pricing </h2> <p>No server compute to pay for → no subscription. You own it once.</p> <p>Building 24U solo and in public — privacy-first AI that runs 100% in your browser (competitive analysis, SWOT &amp; content from your data, nothing uploaded). I'm all-in and running lean. If it resonates, support means the world — backers get a free lifetime license 🙏 ko-fi.com/lukaszdev</p> <p>Curious what the dev crowd thinks of in-browser inference as a privacy pattern — would you trust "runs locally" over "we promise we don't read your data"?</p> <p>Try it: <a href="https://24-u.vercel.app/landing" rel="noopener noreferrer">https://24-u.vercel.app/landing</a></p> webdev ai showdev javascript