SOLID Principles Course
This course teaches SOLID principles through designing extensible subscription and payment systems, covering domain modeling, payment flows, notifications, and safe extension techniques.

4 to 360h flexible workload
certificate valid in your country
What will I learn?
This SOLID Principles Course shows you how to design clean, extensible subscription and payment systems with real-world patterns. Learn domain modelling for users, subscriptions, and invoices, robust payment flows, and flexible notification channels. You will practise abstractions, dependency injection, testing strategies, and safe extension techniques to add new payment methods and channels without breaking existing code.
Elevify advantages
Develop skills
- Model subscription lifecycles: design clear states for billing and access control.
- Architect payment flows: build SOLID, testable adapters for cards, PayPal, and more.
- Design pluggable notifications: add email, SMS, and push without core rewrites.
- Apply SOLID in practice: cut coupling, boost cohesion in real backend modules.
- Extend safely: add payment methods and channels using OCP and DIP patterns.
Suggested summary
Before starting, you can change the chapters and the workload. Choose which chapter to start with. Add or remove chapters. Increase or decrease the course workload.What our students are saying
Your classes are perfect. I got the one-year package and finally have the chance to follow several topics I'm interested in without having to switch platforms... thank you for everything you do, I've already recommended you to others...

Giulio CarloDigital Marketing Student
I like how the lessons get straight to the point and how I can switch chapters and skip content I don't need.

Mariana FerresPhotography Student
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Luciana AlvarengaNail Design Student
The platform is fast and easy to use. The variety of content and the extra videos really help with learning.

Giulio CarloPrompt Engineering Student
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