Handling API Data in Next.js: Things I Learned While Working on Real Projects

Hi everyone,

Over the past few years I’ve mostly worked with React and React Native, but more recently I started working more with Next.js for web applications.

One area where I learned a lot was handling API data in production applications. In tutorials everything looks simple, but in real projects things become a bit more complicated.

I wanted to share a few things that helped me while working on Next.js applications that rely heavily on APIs.

1. Choosing the right data fetching approach

One thing that confused me at the beginning was when to fetch data on the server and when to fetch it on the client.

Next.js gives several options:

• Server components
• Client-side fetching
• API routes
• Static generation

At first I used client-side fetching for almost everything because it was similar to how I worked with React.

But later I realized that some pages worked much better when data was fetched on the server side, especially pages that needed fast loading and good SEO.

Now I usually think about these questions first:

• Does the page need SEO?
• Does the data change frequently?
• Does the page require user interaction?

This helps decide the best approach.

2. Managing API calls properly

In a few projects we noticed that the UI was making too many API requests, especially when users navigated between pages.

This caused unnecessary loading states and sometimes slower performance.

To improve this, we started using TanStack Query (React Query) for managing API data.

This helped us with:

• caching API responses
• reducing duplicate requests
• better handling of loading and error states

After introducing it, the application felt much smoother.

3. Handling loading states carefully

One mistake I made earlier was not thinking enough about loading states.

Sometimes the UI would look empty while waiting for API data, which made the application feel broken.

Now I usually:

• show skeleton loaders
• display clear loading indicators
• handle errors gracefully

These small UI details improve the overall experience a lot.

4. Debugging API issues

One thing that always happens in real projects is unexpected API errors.

Sometimes the issue is in the frontend, sometimes in the backend, and sometimes it's just a configuration problem.

When debugging API issues I usually follow a simple process:

1. Check the Network tab in the browser
2. Verify request headers and payload
3. Test the API in Postman or curl
4. Check backend logs if possible

Many times the issue turns out to be something simple like a missing header or incorrect request body.

5. Environment variables and deployment

Another issue I ran into was APIs working locally but failing in production.

In many cases the problem was related to environment variables.

Now I always double-check:

• .env.local
• deployment environment variables
• API base URLs

This avoids a lot of confusion during deployment.

Final thoughts

Working with Next.js in production taught me that handling API data properly is just as important as writing good UI code.

Frameworks make many things easier, but real-world applications always introduce small challenges that you only learn by experience.

I’m still learning better patterns for structuring applications and managing data efficiently.

If you’ve worked on Next.js projects, I’d be curious to hear what challenges you faced while handling APIs.

Thanks for reading.