10 Common Mistakes When Deploying with Vercel and How to Avoid Them

Deploying with Vercel is often touted as a straightforward process, but that doesn't mean things can't go wrong. As indie hackers and solo founders, we know that every minute spent troubleshooting deployment issues is time away from building the next great feature. In this guide, we'll cover the 10 most common mistakes we’ve encountered while deploying with Vercel in 2026 and how to avoid them.

1. Ignoring Environment Variables

What Happens

Many developers overlook the need to configure environment variables correctly. This can lead to broken functionalities or errors in production.

Solution

Always double-check your environment variables in Vercel’s dashboard before deploying. Use the "Environment Variables" section to ensure everything is set up as intended.

2. Not Using the Correct Build Command

What Happens

If you don’t specify the correct build command, Vercel may not build your application correctly, leading to a broken deployment.

Solution

Make sure you specify the right build command in your project settings. For example, for a Next.js app, this is usually next build.

3. Overlooking the Output Directory

What Happens

Deploying from the wrong output directory can result in missing files or broken links.

Solution

Check your project’s settings and ensure that the output directory matches where your build files are located. For Next.js, this is usually .next.

4. Not Configuring Custom Domains Properly

What Happens

Failing to set up custom domains can lead to accessibility issues for users trying to reach your application.

Solution

Follow Vercel's documentation to add and configure custom domains correctly. Make sure to set up DNS records as instructed.

5. Forgetting to Optimize Images

What Happens

Large images can slow down your site, affecting performance and user experience.

Solution

Use Vercel's built-in Image Optimization feature or tools like ImageKit to ensure your images are properly optimized before deployment.

6. Skipping on Testing Before Deployment

What Happens

Deploying without testing can lead to unexpected errors in production.

Solution

Utilize Vercel’s Preview Deployment feature for testing before going live. This allows you to catch issues in a staging environment.

7. Not Monitoring Performance

What Happens

Failing to monitor your deployment can lead to performance issues going unnoticed until users complain.

Solution

Use Vercel Analytics to track performance metrics. Set alerts for any performance degradation to address issues proactively.

8. Ignoring Serverless Function Limits

What Happens

Vercel has specific limits on serverless functions, and exceeding these can cause your functions to fail.

Solution

Review Vercel's documentation on serverless function limits. Optimize your functions to stay within these limits, and consider alternative architectures if needed.

9. Neglecting to Update Dependencies

What Happens

Outdated dependencies can lead to security vulnerabilities and compatibility issues.

Solution

Regularly check for updates in your package.json and use tools like Dependabot to automate this process.

10. Not Utilizing the Vercel CLI

What Happens

Many developers rely solely on the Vercel dashboard, which can be limiting and inefficient.

Solution

Get comfortable using the Vercel CLI for deployment. It provides more control and allows for easier troubleshooting.

| Mistake | Impact | Solution | Tools/Features | |-------------------------------|-------------------------------------|-------------------------------|-------------------------------| | Ignoring Environment Variables | Broken functionality | Check dashboard | Environment Variables | | Not Using the Correct Command | Incorrect build | Specify right command | Build Settings | | Wrong Output Directory | Missing files | Verify output directory | Output Directory Settings | | Custom Domain Issues | Accessibility problems | Configure DNS correctly | Custom Domains | | Unoptimized Images | Slower performance | Use Image Optimization | Vercel Image Optimization | | Skipping Testing | Production errors | Use Preview Deployments | Preview Deployments | | No Performance Monitoring | Undetected performance issues | Use Vercel Analytics | Vercel Analytics | | Ignoring Serverless Limits | Function failures | Review limits | Serverless Function Limits | | Outdated Dependencies | Security vulnerabilities | Regularly update | Dependabot | | Not Using Vercel CLI | Limiting deployment capabilities | Learn Vercel CLI | Vercel CLI |

Conclusion

Deploying with Vercel can be smooth if you avoid these common pitfalls. Start by checking your environment variables and build commands, and make it a habit to test thoroughly before going live. Keep your dependencies updated and monitor your performance actively.

If you're just getting started, focus on these foundational elements to streamline your deployment process.

For your next deployment, start here: ensure your environment setup is solid and leverage the tools Vercel provides.