
You’ve been there: Your Unit tests pass both locally and in CI. You deploy with confidence. You thought.. Then staging in the real cloud reveals the truth—bugs that only show up with actual RDS parameter settings, real SQS and SNS throughput limits, or Lambda and API Gateway behaviour your local mocks never captured.
The solution is Testcontainers.
Testcontainers is a testing library that provides easy and lightweight APIs for bootstrapping integration tests with real services wrapped in Docker containers. Using Testcontainers, you can write tests talking to the same type of services you use in production without mocks or in-memory services. Spin them up, run migrations, execute your Node.js service against them, assert results, auto-cleanup.

Debugging serverless functions has always been challenging, often requiring repeated invocations, extensive log tracing, and cloud deployments to diagnose an issue. The new Lambda Debug Mode in LocalStack changes this by allowing developers to debug AWS Lambda functions directly in their IDE, with breakpoints, variable inspection, and step-through execution, without leaving their local environment. In this presentation, Marco Edoardo Palma provides a hands-on demo of Lambda Debug Mode—from debugging standalone functions to handling multi-function workflows. Learn how this developer-first approach makes debugging serverless applications faster, smoother, and more intuitive.

Ever wish you could test your whole cloud app without touching the cloud? I’ll show you how to validate your serverless pipeline from start to finish, right on your laptop using LocalStack. Join our Slack community and start shipping with confidence.

In this live session, Brian from LocalStack will demonstrate the WireMock extension for LocalStack, showing how developers can achieve end-to-end local testing by combining AWS service emulation with external API mocking. Brian will walk through real-world use cases, demonstrate the integration in action, and explain how this unified approach simplifies testing complex cloud applications that depend on both AWS services and third-party APIs.