🧠 How do you add new logic in .NET — without touching existing code? This blog breaks down the Open/Closed Principle (OCP) with a tax calculation example in C#. ✅ Add new business rules and logics ✅ Keep current logic untouched ✅ Use DI + Factory + Interface combo Less regressions. More testability. Cleaner code. 🔗 Read now: https://ilovedotnet.org/blogs/open-closed-principle-in-solid