10 Common Mistakes Developers Make with Vercel and How to Avoid Them

As a developer using Vercel, you might feel like you’re riding a wave of deployment bliss. But let’s be real: even the smoothest waves can have unexpected riptides. In 2026, we’ve seen a lot of developers stumble into common pitfalls that can derail their projects. I’ve encountered many of these myself, and I’m here to share the top mistakes and how to sidestep them.

1. Ignoring Environment Variables

What Happens

One of the most common mistakes is not properly setting up environment variables. This can lead to issues where your application works locally but fails on deployment.

How to Avoid It

Make sure to define all necessary environment variables in the Vercel dashboard. Use the .env file locally and replicate those settings in Vercel’s project settings.

Our Take

We had a project where API keys were hardcoded for local development, and it crashed during deployment. Now, we always double-check our environment variables before hitting "deploy."

2. Overlooking Build Settings

What Happens

Vercel automatically detects your build settings, but if you have a custom configuration, it’s easy to overlook this.

How to Avoid It

Always specify your framework and build commands in the Vercel settings. For example, if you’re using Next.js, ensure that your build command is set to next build.

Our Take

We initially left the default settings for a Next.js project and ran into issues with SSR. Now, we customize our build settings every time.

3. Not Utilizing Preview Deployments

What Happens

Deploying directly to production without testing can lead to broken features and unhappy users.

How to Avoid It

Take advantage of Vercel's Preview Deployments. Every pull request can trigger a preview deployment, allowing you to test changes before going live.

Our Take

This feature saved us from deploying a broken feature last month. We now use it religiously for every PR.

4. Forgetting to Set Up Custom Domains

What Happens

Many developers forget to configure custom domains, leading to confusion and a lack of professionalism.

How to Avoid It

Link your custom domains in the Vercel dashboard and ensure DNS settings are correctly pointed to Vercel.

Our Take

We launched a site without a custom domain once, and it felt unprofessional. Now, custom domains are one of the first things we set up.

5. Mismanaging File Structure

What Happens

Vercel has specific requirements for file structure, especially with Next.js. Misplacing files can lead to build failures.

How to Avoid It

Follow the framework guidelines and keep your pages directory intact. Ensure that your public assets are in the public folder.

Our Take

We had a case where a file was in the wrong directory, causing a 404 on deployment. We now keep a checklist for our file structure.

6. Ignoring Analytics and Monitoring

What Happens

Deploying without setting up monitoring can lead to issues going unnoticed until it’s too late.

How to Avoid It

Set up Vercel Analytics or integrate third-party monitoring tools like Sentry or LogRocket to catch errors and performance issues early.

Our Take

We missed a critical performance issue on our last project until users complained. Analytics is now a mandatory setup step for us.

7. Not Configuring Redirects Properly

What Happens

Misconfigured redirects can lead to broken links and a poor user experience.

How to Avoid It

Use the vercel.json file to define any necessary redirects clearly.

Our Take

We once had a major URL change and forgot to set up redirects, losing traffic. Now, we always configure redirects with every major change.

8. Skipping Caching Strategies

What Happens

Not utilizing caching can slow down your application and increase loading times.

How to Avoid It

Implement caching strategies in your application and use Vercel's caching features to optimize performance.

Our Take

We learned the hard way that proper caching can significantly reduce load times. We now have caching strategies documented for each project.

9. Neglecting to Test Locally

What Happens

Assuming everything works in production without local testing can lead to unexpected errors.

How to Avoid It

Always run your application locally with the same environment settings as Vercel before deploying.

Our Take

We’ve had several embarrassing moments where features worked locally but failed in production. Testing locally is non-negotiable now.

10. Not Keeping Up with Vercel Updates

What Happens

Vercel frequently updates its features and functionalities, and missing these can lead to missed opportunities.

How to Avoid It

Follow Vercel's changelog and community updates to stay informed about new features and best practices.

Our Take

We recently integrated a new feature from Vercel that improved our deployment speed significantly. We now make it a point to check for updates regularly.

Conclusion

To make the most out of Vercel in 2026, avoid these common mistakes by following the outlined strategies. Start by setting up your environment variables and custom domains, and make use of preview deployments to test your changes.

Start here: If you’re new to Vercel, I recommend diving into the official documentation and setting up a simple project to experiment with these practices.