Component Design: Think Before You Code

The Problem: Coding Without Thinking

Let’s imagine: You get a new feature request, open your code editor, and immediately start typing. Sound familiar? Most developers fall into this trap – we dive straight into coding without taking a moment to think about the structure and design of what we are building.

This “code first, think later” approach leads to a cascade of problems:

Messy, unreadable code that’s hard to maintain
Hours spent refactoring what could have been written cleanly from the start
Components that do too many things at once
Code that’s difficult to test and reuse
Endless debugging sessions trying to sort out complex logic

The truth is, we often write code randomly and then spend precious time refactoring it later. But what if there was a better way?

The Solution: Component Design Thinking

Component design is the practice of thinking through your component structure before writing a single line of code. It’s about asking the right questions upfront:

What is this component’s single responsibility?
How can I break this down into smaller, manageable pieces?
What will my component hierarchy look like?
How will these components interact with each other?

Good developers are the ones who refactor less code, not because they are lazy, but because they invest time in thinking before coding. This approach saves enormous amounts of time in the long run.

Why Component Design Matters

When you practice component design, you get several benefits:

Less Refactoring: Your code architecture is thought out from the beginning, reducing the need for major structural changes later.
Modular Code: Each component has a clear purpose and can be easily understood, modified, and reused.
Better Testability: Smaller, focused components are much easier to test than large, multi-purpose ones.
Improved Readability: Your code tells a story that other developers (including future you) can easily follow.
Easier Maintenance: When bugs arise or features need updates, you know exactly where to look and what to change.

The SOLID Principles in Component Design

The SOLID principles, especially the Single Responsibility Principle (SRP), are crucial for component design:

Single Responsibility Principle: Every component should have one reason to change. If your component file is over 150 lines, it’s probably doing too much.

Example: Instead of creating one massive ProductCard component that handles displaying product info, managing wishlist state, handling purchase logic, and showing promotional labels, break it down:

ProductCard → Displays basic product information
WishlistButton → Handles wishlist functionality
PurchaseButton → Manages purchase logic
PromotionalLabel → Shows special offers or “New” labels

Component Composition: Building with Lego Blocks

Think of components like Lego blocks. Each piece serves a specific purpose, but when combined, they create something more complex and beautiful. This is component composition – building larger features by combining smaller, focused components.

For example, a “New” label on some product cards:

Card component → SRP: showing card information

LabeledCard component (Higher Order Component) → Takes any card component and adds a label to it

This approach means you can reuse the basic `Card` anywhere, and the labeling logic is separate and reusable too.

Let’s look at how YouTube handles its navigation to understand good component design in action.

Collapsed state
Expanded state

The Challenge

YouTube has a hamburger menu in the header, but the navigation panel appears in the body. The navigation has two states:

Collapsed: Shows just icons with minimal labels
Expanded: Shows full menu items, section headings, and requires scrolling

The key question: Should the left navigation be part of the header or the body?

The Bad Implementation

Many developers might structure it like this:


<Header>
  <MenuButton>
  <LeftNavigation>
</Header>

<Body>
  <!-- Main content -->
</Body>

This creates major problems:

CSS Alignment Issues: The main content area doesn’t know about the navigation width
Responsive Challenges: Hard to adjust layout when navigation expands/collapses
State Management Complexity: Navigation state affects both header and body layouts

The Good Implementation

YouTube’s approach (and what you should do):


<Header>
  <MenuButton>
</Header>

<Body>
  <LeftNavContainer>
    <CollapsedMenu>
      <Item1>
      <Item2>
      <Item3>
    </CollapsedMenu>
    <ExpandedMenu>
      <Section1>
        <Heading>
        <ExpandedItem1>
        <ExpandedItem2>
      </Section1>
    </ExpandedMenu>
  </LeftNavContainer>
  <MainContent>
    <!-- Your main content here -->
  </MainContent>
</Body>

Why This Works Better

Layout Control: The main container can easily adjust its width based on navigation state since both are in the same parent container.

Separate State Management: Collapsed and expanded menus are separate components, making it easy to conditionally render the appropriate one.

CSS Simplicity: No complex positioning required – everything flows naturally.

Testing Made Easy: You can test collapsed and expanded states independently.

Performance Benefits: Supports lazy loading and code splitting – you can load expanded menu components only when needed.

Common Mistakes Developers Make

Adding navigation to the header when it should be in the body
Not separating expanded and collapsed states into different components
Writing components over 150 lines without breaking them down
Mixing multiple responsibilities in a single component
Skipping the design phase and jumping straight into coding

Additional Benefits of Good Component Design

Code Splitting and Lazy Loading

Well-designed components enable better performance optimization. Take MakeMyTrip’s website as an example – it has flights, hotels, homestays, trains, and buses sections. Instead of loading all components at once, they can:

Load only flight-related components when user is on flights tab
Lazy load hotel components when user switches to hotels
This reduces initial bundle size and improves page load times

Better Debugging

When something breaks, you know exactly which component is responsible. No more hunting through a 500-line component file trying to find the bug.

Team Collaboration

Clear component boundaries make it easier for multiple developers to work on the same feature without stepping on each other’s toes.

Getting Started with Component Design

Here’s a simple process to follow:

Understand the Requirements: What exactly needs to be built?
Identify Responsibilities: What are the different things this feature needs to do?
Draw the Component Tree: Sketch out how components will be nested
Define Component Boundaries: What props will each component receive?
Consider State Management: Where will state live and how will it flow?
Think About Reusability: Can any of these components be used elsewhere?
Start Coding: Now you’re ready to write clean, purposeful code

Conclusion

Component design isn’t about being slow or over-engineering – it’s about being smart with your time and effort. The few minutes you spend thinking upfront will save you hours of refactoring later.

Remember: Good developers are ones who refactor less, not because they write perfect code, but because they think before they code.

Start practicing component design today. Your future self (and your teammates) will thank you for it. Take time to think through your component hierarchy, keep responsibilities separate, and watch as your code becomes more modular, readable, reusable, and testable.

The next time you’re about to start coding, pause and ask yourself: “How should I design this?” Your code quality will improve dramatically, and you’ll spend less time debugging and more time building amazing features.