How do you create route groups in the App Router?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Next.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
Route groups allow you to organize routes without affecting the URL structure. You create them by wrapping folder names in parentheses ().
app/
├── (marketing)/
│ ├── about/
│ │ └── page.js // /about
│ └── contact/
│ └── page.js // /contact
├── (shop)/
│ ├── products/
│ │ └── page.js // /products
│ └── cart/
│ └── page.js // /cart
└── layout.js // Shared layout
Route groups are useful for organizing code, creating different layouts for different sections, or conditionally including layouts.
Candidate Response Strategy & Interview Tips
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- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
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