SOLID vs YAGNI
SOLID (Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion) and YAGNI (You Aren't Gonna Need It) 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: SOLID refers to single-responsibility, open-closed, liskov, interface-segregation, dependency-inversion, while YAGNI refers to you aren't gonna need it — they describe different things even when they show up in the same sentence.
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.
YAGNI — You Aren't Gonna Need It
Principle that says don't build features until they're actually required. YAGNI is the antidote to speculative generality — most "we might need this someday" code never gets used.
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.
When to use YAGNI
Reach for "YAGNI" when the conversation is specifically about you aren't gonna need it. Principle that says don't build features until they're actually required. YAGNI is the antidote to speculative generality — most "we might need this someday" code never gets used.
FAQs
What is the difference between SOLID and YAGNI?
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. YAGNI stands for You Aren't Gonna Need It — Principle that says don't build features until they're actually required. YAGNI is the antidote to speculative generality — most "we might need this someday" code never gets used.
Are SOLID and YAGNI the same thing?
No. They're often used in the same conversation because they're related, but they describe different concepts. SOLID = Single-responsibility, Open-closed, Liskov, Interface-segregation, Dependency-inversion. YAGNI = You Aren't Gonna Need It.
When should I use SOLID vs YAGNI?
Use SOLID when you're specifically referring to single-responsibility, open-closed, liskov, interface-segregation, dependency-inversion. Use YAGNI when the topic is you aren't gonna need it.