---
title: "Troubleshooting"
description: "If you need help solving issues with your Sentry JavaScript AWS Lambda SDK, you can read the edge cases documented below."
url: https://docs.sentry.io/platforms/javascript/guides/aws-lambda/troubleshooting/
---

# Troubleshooting | Sentry for AWS Lambda

Events Missing Right After Lambda Coldstart

Events might be missing right after a Lambda function coldstart. This is a [known issue](https://github.com/getsentry/sentry-javascript/issues/18107) which we are still investigating. Events are sent for subsequent function invocations.

Span Names Show Lambda Function Name Instead of Request Path with Express

When using `@sentry/aws-serverless` with Express, span names are based on the AWS Lambda function name from the Lambda context, rather than the HTTP request path. This differs from `@sentry/node` behavior where span names show the request path.

This is expected behavior for the AWS Lambda SDK. See the [related GitHub issue](https://github.com/getsentry/sentry-javascript/issues/15788) for more details.

Missing Tracing Data when using Infrastructure as Code Frameworks (e.g. CDK, Serverless, SST, etc.)

When using Infrastructure as Code frameworks (e.g. CDK, Serverless, SST, etc.) that bundle everything into a single file, third-party libraries that need to be instrumented by Sentry (such as `express`, `pg`, etc.) must be marked as external and excluded from the bundle. If these libraries are bundled, Sentry cannot instrument them properly, resulting in missing tracing data.

You can include them via a Lambda layer so that your function can still access them at runtime.