From Microservices to Monetization: Building a Real Estate Platform the Right Way

#webdev #programming #productivity #devops

Intro Section:

After 15 years in software development and test automation, I decided to build something of my own — a real estate (Immobilien) platform tailored for the German market.

The idea was to combine what I know best: robust backend architecture, modern TypeScript frontends, and secure authentication — all designed from the ground up for monetization.

This article walks through the architectural decisions, technical challenges, and hard-earned lessons that shaped the platform.

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🧱 Why Microservices?

I started with one clear goal: keep things clean and scalable. The platform includes:
• 🏘️ Multiple property types (house, apartment, garden…)
• 📦 Listings for rent and purchase
• 📸 File uploads for property photos
• 🧭 Address-to-Geo translation (lat/lng)
• 🔐 Secure login with role-based access

So I split it into microservices:
• property-service: manages property-related data
• auth-service: authentication via Keycloak
• geo-service: converts addresses into coordinates
• upload-service: handles image/file storage in PostgreSQL
• gateway-service: central API routing via Spring Cloud Gateway

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⚙️ Key Technical Choices

UUIDs for IDs:
Avoided collisions and made frontend caching simpler.

Database Design:
Separate tables for property types (Apartment, House, etc.) and for listing types (Rent, Buy) for performance.

File Uploads in PostgreSQL:
No S3 — I stored images using bytea in PostgreSQL. It’s fast and GDPR-friendly for MVP stage.

Keycloak Auth:
It powers:
• Login/Signup
• RBAC (Admin, Agent, User)
• JWT-secured APIs

DevOps with ECS + Terraform:
Everything runs in Docker containers on ECS.
Infrastructure is built using Terraform (VPCs, services, secrets).

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🖼️ Frontend Stack
• Next.js + TypeScript
• Tailwind CSS
• Geoapify for address autocomplete
• Access tokens from Keycloak for secure API use

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💡 Lessons Learned
• Don’t overgeneralize — real estate data is domain-specific
• Start with a Gateway service — saves major refactoring later
• Separate out audit/analytics early
• Keycloak is great but painful to customize

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🚀 What’s Next?
• 💳 Integrate Stripe for paid listings
• 🔔 Notify users of search matches
• 📊 Add analytics microservice
• 🗺️ Improve map-based UX

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✌ Final Thoughts

If you’re considering building your own SaaS — go for it.
Start small, think in services, and build around real use cases.