DRY vs SOLID

DRY (Don't Repeat Yourself) and SOLID (Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion) both come up in technology conversations and get confused. Here's the plain-English difference, side by side, so you can use each one with confidence.

The key difference: DRY refers to don't repeat yourself, while SOLID refers to single-responsibility, open-closed, liskov, interface-segregation, dependency-inversion — they describe different things even when they show up in the same sentence.

DRY — Don't Repeat Yourself

Principle that every piece of knowledge should have a single, unambiguous representation in a system. DRY done badly creates the wrong abstractions — duplication is cheaper than the wrong coupling.

Full DRY definition →

SOLID — Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion

Five object-oriented design principles that make code easier to extend and harder to break. SOLID is the grammar of professional codebases — not a recipe, but a shared vocabulary.

Full SOLID definition →

When to use DRY

Reach for "DRY" when the conversation is specifically about don't repeat yourself. Principle that every piece of knowledge should have a single, unambiguous representation in a system. DRY done badly creates the wrong abstractions — duplication is cheaper than the wrong coupling.

When to use SOLID

Reach for "SOLID" when the conversation is specifically about single-responsibility, open-closed, liskov, interface-segregation, dependency-inversion. Five object-oriented design principles that make code easier to extend and harder to break. SOLID is the grammar of professional codebases — not a recipe, but a shared vocabulary.

FAQs

What is the difference between DRY and SOLID?

DRY stands for Don't Repeat Yourself — Principle that every piece of knowledge should have a single, unambiguous representation in a system. DRY done badly creates the wrong abstractions — duplication is cheaper than the wrong coupling. SOLID stands for Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion — Five object-oriented design principles that make code easier to extend and harder to break. SOLID is the grammar of professional codebases — not a recipe, but a shared vocabulary.

Are DRY and SOLID the same thing?

No. They're often used in the same conversation because they're related, but they describe different concepts. DRY = Don't Repeat Yourself. SOLID = Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion.

When should I use DRY vs SOLID?

Use DRY when you're specifically referring to don't repeat yourself. Use SOLID when the topic is single-responsibility, open-closed, liskov, interface-segregation, dependency-inversion.