Show HN: Fakecloud – Free, open-source AWS emulator | Hacker News Reader

Show HN: Fakecloud – Free, open-source AWS emulator

github.com

37 pointslucas_vieira9 comments

Thank you for sharing this! It looks like a very useful tool, especially for those of us who got burned by LocalStack's auth token requirement breaking CI pipelines.

Built this after LocalStack started requiring an auth token in March and broke our CI.

Great timing with this — the LocalStack auth token change broke a lot of CI pipelines. Nice to see a Rust-based alternative with that kind of startup time (~500ms, 10 MiB idle).

The "real PostgreSQL/Redis behind RDS/ElastiCache" approach is the right call. We run PHP integration tests against SQS and S3, and the biggest pain with mocked services is subtle behavioral differences that only show up in production. Having actual protocol conformance validated against Smithy models is a big deal.

One question: any plans for async event delivery for SNS/EventBridge? In our setup we test fan-out patterns where message ordering and delivery timing matter — curious how Fakecloud handles that vs real AWS eventual consistency.

SNS fan-out to SQS works today with filter policies, and EventBridge is implemented with rule matching and targets. Delivery is synchronous by default (deterministic for tests), but I'm planning a `/_fakecloud/config/sns` API to let you configure delivery delays, ordering, and failure rates per topic. That way you can test eventual consistency scenarios without changing your app code. Also, a PHP SDK is in the works and should be out by end of day.

> PHP SDK is in the works and should be out by end of day Glad to hear that! Thank you!

This is sold as an emulator, but couldn't it inadvertently replace AWS entirely in production too?

Oh please don't do it, it's not for that and never will be. It's not designed for scale, or durability.

That's great! Thanks for building this

Really impressive

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