What changed
AWS launched AWS Emulator, a Rust-based local environment that accepts the same AWS CLI and SDK calls over a local HTTPS endpoint. It is free to run, available as Linux packages or a Docker container on macOS and Windows, and its source is on GitHub.
Why it matters
Coding agents and developers can test cloud-facing changes without provisioning live resources for every iteration. Fidelity, service coverage and the gap to deployed AWS still need explicit verification.
What to do
Move one low-risk integration test to the emulator, run the same case against a disposable AWS account, and record unsupported APIs, identity differences and cleanup behavior before expanding use.
Caveat
AWS describes broad service compatibility and behavioral fidelity, but it is not the production control plane and cannot prove IAM, regional, quota, latency or service-specific behavior in a real account.