What Is the Open-Closed Principle? Extension, Abstraction, Plug-ins and the Expression ProblemThe open-closed principle says that a module should be open to new behaviour and closed to edits of the code … Oct 21, 2026 · 27 min What Is Inversion of Control? Frameworks, Callbacks, Dependency Injection and ContainersInversion of control is what happens when someone else's code decides when yours runs, or what it works with. … Oct 20, 2026 · 27 min