How do you effectively manage S3 security as your usage expands?

Most people don’t use Macie unless they're required to due to compliance issues since it can be pricey for what it offers. Instead, here's what works at a smaller scale:

1. Turn on S3 Block Public Access at the account level. This one switch can prevent about 90% of S3 exposure incidents.
2. Use Access Analyzer for S3, which is free and can flag any unintended external access to buckets.
3. Implement a solid naming convention like `{env}-{service}-{purpose}`, and set up lifecycle policies to automatically delete any buckets with 'test' or 'tmp' in their names after 30 days.
4. Use AWS Config to ensure server-side encryption is enabled for all buckets, helping to sidestep unencrypted ones before they become an issue.

Also, be cautious with overly permissive IAM policies—they can expose your buckets more than you think, even if they aren’t publicly accessible.

You might be managing an AWS account with all your systems in one place? It's usually better to have separate accounts for different systems to manage resources better, allocate costs accurately, and keep sensitive information secure.

Change control is crucial! Whenever something goes live, we make sure it's documented. It helps us understand what’s real from a business standpoint in case something goes wrong. A well-implemented change control system provides clarity and can save a lot of headaches when things break unexpectedly, even if it's perceived as a bureaucratic hassle.

Definitely start tagging your buckets and ensuring you have an identified owner for each one. This lets you manage and review access permissions effectively. Creating budgets based on tags can also provide insights into your usage.

At your level with 20-30 buckets, managing everything with Terraform can be really effective. Integrating it with CI/CD practices helps enforce naming conventions as your S3 usage grows. For larger setups, like ours with a thousand accounts, you might need dedicated teams to oversee everything. The key is to try and prevent issues upfront rather than just auditing afterwards.