YAGNI (You Aren't Gonna Need It) in LLD - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does YAGNI stand for in system design?

YAGNI stands for "You Aren't Gonna Need It." It means do not add features or complexity until they are actually needed.

beginner

Why is following YAGNI important in software architecture?

Following YAGNI helps keep the system simple, reduces wasted effort, and avoids unnecessary complexity that can make maintenance harder.

intermediate

How does YAGNI relate to scalability in system design?

YAGNI encourages building only what is needed now, which helps focus on real requirements and prevents over-engineering that can slow down scaling.

intermediate

Give an example of violating YAGNI in a system design.

Adding a complex user role system before any users need different roles is a violation of YAGNI because it adds unnecessary complexity early.

beginner

How can YAGNI improve team productivity?

By focusing only on needed features, teams avoid spending time on unused code, which speeds up development and reduces bugs.

What is the main idea behind YAGNI?

A Only build features when they are actually needed

B Build all possible features upfront

C Ignore user requirements

D Add complexity to prepare for future needs

YAGNI means you should only build features when they are actually needed to avoid unnecessary work.

Which of the following is a risk of ignoring YAGNI?

A Simpler codebase

B Faster development

C Unnecessary complexity

D Better user experience

Ignoring YAGNI often leads to unnecessary complexity that makes the system harder to maintain.

YAGNI helps teams to:

A Predict all future needs

B Focus on current requirements

C Write more code

D Ignore testing

YAGNI encourages focusing on current requirements rather than speculative future needs.

Which practice aligns with YAGNI?

A Adding features based on assumptions

B Building complex frameworks before use

C Over-engineering for scalability

D Waiting to add features until users request them

Waiting to add features until they are requested aligns with YAGNI principles.

YAGNI is most closely related to which software development principle?

A KISS (Keep It Simple, Stupid)

B DRY (Don't Repeat Yourself)

C SOLID principles

D Continuous Integration

YAGNI supports KISS by avoiding unnecessary complexity.

Explain the YAGNI principle and why it is important in system design.

Think about building only what you need now, not what you might need later.

Describe a scenario where ignoring YAGNI could cause problems in a software project.

Consider building a feature no one asked for yet.