The latest articles on Forem by olivier delfosse (@olivier_delfosse_6df9f498). https://forem.com/olivier_delfosse_6df9f498 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%2F3572776%2F975e7281-23b7-4317-83e9-16c17e6eabd2.jpg https://forem.com/olivier_delfosse_6df9f498 en olivier delfosse Sat, 18 Oct 2025 16:34:26 +0000 https://forem.com/olivier_delfosse_6df9f498/i-built-a-nextjs-ai-app-that-turns-any-book-into-a-character-map-49h0 https://forem.com/olivier_delfosse_6df9f498/i-built-a-nextjs-ai-app-that-turns-any-book-into-a-character-map-49h0 <p><strong>Why I built it:</strong></p> <p>I love complex stories, but I always forget who’s who when I come back to a book.<br> So I built Booklaxy, a web app that generates interactive character maps and spoiler-free summaries using AI.</p> <p><strong>What it does</strong> </p> <ul> <li>🧩 AI-generated summaries per chapter</li> <li>🌌 Visual character relationships (interactive graph)</li> <li>📝 Personal notes and book wiki</li> </ul> <p>👉 Try it here → booklaxy.com</p> <p><strong>How I built it</strong></p> <p>Tech stack:<br> Next.js 14, MongoDB Atlas, Gemini AI, Tailwind CSS, GCP cloud run</p> <p><strong>What I learned</strong></p> <ul> <li>Gemini handles multilingual books well, but prompt updates can break old results =&gt; always test to avoid regressions! (more complex that the basic tests)</li> <li>AI integration with the App is always heavier than it looks: design, async logic and retries add unexpected complexity.</li> </ul> <p><strong>Looking for feedback</strong></p> <p>I’d love to get feedback from fellow builders:</p> <ul> <li>How would you improve the onboarding UX?</li> <li>For those who’ve built prompt-based AI APIs, any tricks to keep things stable and efficient? :) </li> </ul> nextjs ai sideprojects d3js