Fix ConnectionError Error in TypeScript — When Deploying

What Is the ConnectionError Error?

Developers working with TypeScript often hit the ConnectionError error unexpectedly. Understanding why it occurs is the first step to fixing it.

Why It Happens

This error indicates a failed network connection — typically caused by incorrect URLs, DNS issues, or the server being unreachable. During deployment, this often surfaces due to missing environment variables or build config differences.

The Fix

async function fetchWithRetry(url, retries = 3) {
  for (let i = 0; i < retries; i++) {
    try {
      return await fetch(url);
    } catch (err) {
      if (i === retries - 1) throw err;
      await new Promise(r => setTimeout(r, 1000 * (i + 1)));
    }
  }
}

Related Errors

This error is often accompanied by other issues in your TypeScript application. Check for related warnings in your console output that might provide additional context. Sometimes what appears to be a ConnectionError error is actually a symptom of a deeper configuration problem. Review your application's dependency versions to ensure compatibility, and check that all required environment variables are properly set in your deployment configuration.

Prevention

Set up [Bugsly](https://bugsly.dev) to catch this and similar errors in production with detailed stack traces and environment info.

Key Takeaways

• Always handle this error gracefully with proper error handling
• Check your environment configuration — especially when deploying
• Test thoroughly before deploying to production