Awesome
Bucket Snake
This project is in heavy development and not yet ready for production use
<p align="center"><img src="website/static/img/logo.png" alt="logo" width="30%" height="30%" /></p>Bucket Snake is an AWS Lambda function that provisions S3 access for IAM roles. A primary feature of Bucket Snake is to create IAM roles that reside in the account where the S3 buckets live to facilitate proper cross-account S3 bucket access (via a role assumption).
Documentation
Bucket Snake's documentation can be found here.