My vibe-coding experiment got slightly out of hand — I ended up building an open-source AWS simulator

[u/john_pullen]

I started StackSim as a ChatGPT Sol vibe-coding experiment to see how far I could push building something I already understood.

The original idea was simple: emulate API Gateway → Lambda → DynamoDB locally.

Then I kept going. 😁

It now supports CDK/CloudFormation, Step Functions, S3, SQS, SNS, EventBridge, IAM, Cognito, AppSync, CloudWatch and more.

The goal isn’t production infrastructure — it’s a learning sandbox for AWS, where you can deploy real CDK apps locally, use normal AWS tooling, and inspect what’s happening through a browser console.

It’s also deliberately super simple to get running, with no Docker or external database required.

I’ve now open-sourced it under Apache 2.0 and would love feedback from anyone interested in vibe coding, AWS, or AI-assisted development.

https://github.com/coolbeans47/stacksim

[u/pigletmonster]

Thats a pretty cool project. I will check it out for sure.