On 11 November 2026 AWS announced AWS Emulator, a local emulator of the AWS APIs that you run on your laptop, a dev server or in CI. The AWS CLI, the AWS SDKs and coding agents such as Kiro and Claude Code talk to it over a local HTTPS endpoint (127.0.0.1:9297) using the same API calls they would send to the cloud; you only change environment variables such as AWS_ENDPOINT_URL. It is written in Rust, is generally available now, costs nothing extra, and is released under CC0 (public domain dedication).
What it covers: AWS says it supports the APIs of AWS services that have an API model in AWS's public API models repository, so requests and errors have the same shape as on AWS. Swami Sivasubramanian's post on Werner Vogels' blog says it is built from more than 400 API models covering more than 200 services; AWS's launch blog gives no count. Calls it has not implemented return HTTP 501. Each release publishes fidelity scores ("k of n" tests matching real AWS), and the tests, including failing ones, are public.
Built by agents: AWS says thousands of autonomous AI agents wrote every line, with agent teams that find gaps against real AWS, write tests, fix issues and review changes, plus an adversarial security agent in the release pipeline. "Our team hasn't written or reviewed any of the code," Senior Principal Engineer Matthew Goldberg writes. The GitHub repository does not take pull requests; bugs and fidelity gaps go to Issues.
Limits at launch: it does not evaluate IAM or resource-based policies the way AWS does, so a request AWS would deny may succeed locally; each instance is a single account (000000000000) with no cross-account or cross-Region behaviour; fidelity varies by service. AWS says not to use it for production or to test security. Anonymous usage telemetry is on by default and can be turned off. Linux gets RPM and Debian packages; macOS and Windows run it in Docker from a Dockerfile in the docs (no ready-made image); building from source needs at least 100 GB of disk. The launch reached 398 points on Hacker News within hours.
