How I Built an AI-Powered Digital Advent Calendar with Angular & Google Gemini

Zoey Haynes — Wed, 05 Aug 2026 09:01:35 +0000

🎯 The Core Problem & Concept

Traditional countdown tools are often static, tedious to fill out day-by-day, or lack engaging UI/UX. My goal was to combine:

Instant Content Generation: Using AI to generate 24+ daily unique surprises (messages, riddles, quotes) tailored to any topic.
Rich Visual Editor: Letting users design individual doors/cases with custom images, text, and password protection.

3. Cross-Platform Access: Web app + dedicated mobile viewer app.

🤖 1. Integrating Google Gemini for AI Content Generation

Filling 24 calendar doors manually can be time-consuming. To solve this, I integrated Google Gemini AI into the creation workflow.

How it works:

The user provides a theme (e.g., "Romantic Holiday Quotes", "Tech Trivia for Developers", "Daily Wellness Tips").
The prompt sent to Gemini specifies structured JSON output for each day (1 to 24), containing a title, description, and keyword tags.
We query Unsplash API using these keyword tags to automatically suggest copyright-free background photos for each door! This reduces calendar creation time from 30 minutes to under 20 seconds. --- ## 🎨 2. Open-Sourcing the Interactive Case Builder One of the biggest technical challenges was building an intuitive WYSIWYG editor for calendar doors — allowing users to customize text styles, image alignment, and secret unlock dates. Instead of keeping this proprietary, we decided to extract the core editor component and open-source it for the Angular community! 👉 Check out the repository on GitHub: github.com/zhaynes067-web/case-builder ### Key Features of Case Builder:
📱 Fully responsive preview mode (mobile & desktop views).
🔒 Support for password-protected secret doors.
🌐 Ready for i18n / multi-language support. Feel free to ⭐ star the repository if you're building interactive Angular tools! --- ## 🚀 3. Tech Stack Summary
Frontend: Angular (Standalone Components, RxJS, NgRx Signal Stores)
Backend: Node.js / Express API
AI Integration: Google Gemini API
Image Integration: Unsplash API

💡 What's Next?

Building DailyReveal has been an incredible journey of combining generative AI with interactive frontend experiences.
If you’d like to try it out or create your own calendar: