LocalEmu

LocalEmu is a free, open-source AWS cloud emulator that runs on your own machine. It speaks the AWS APIs, so the AWS CLI, boto3, Terraform, CDK, and Pulumi you already use work unchanged when you point them at a single local endpoint, http://localhost:4566. There is no AWS account, no credentials, and no cost.

It is a community fork of the LocalStack Community edition, which was archived and moved behind a mandatory account in March 2026. LocalEmu continues that codebase under the Apache 2.0 license, free and tokenless.

Why It Matters for Security Work

A local emulator is a safe place to learn and test cloud security without touching a real account. You can stand up deliberately misconfigured resources (a public S3 bucket, a Lambda leaking secrets, an instance with an open security group), run a scanner against them, see the findings, fix them, and re-scan, all in seconds and at zero cost. Where it counts the behavior is real: Lambda runs in the official AWS runtime images, EC2 instances are containers with security groups enforced by actual packet filtering, and IAM can evaluate policies and deny requests.

Where It Fits

• Local development and fast iteration without a deploy cycle
• CI pipelines that need AWS-shaped services with no account
• Learning a service before touching a real bill
• Testing security tooling and reproducing findings in isolation

It is an emulator, not the real cloud, so it is a complement to scanning real accounts, not a replacement for it.