One of the neat things about AWS is that it's almost twenty years old. One of the unfortunate things about AWS is... that it's almost twenty years old. If you've been using the platform for a while, it can be hard to notice the pace of change in the underlying "foundational" services. More worryingly, even if you're not an old saw at AWS scrying, it's still easy to stumble upon outdated blog posts that speak to the way things used to be, rather than the way they are now. I've gathered some of these evolutions that may help you out if you find yourself confused.

Last Week in AWS is a newsletter and blog providing updates, insights, and commentary on developments within the Amazon Web Services (AWS) ecosystem. Readers can stay informed about new AWS services, feature releases, and industry trends. Additionally, they can learn about best practices for cloud architecture, cost optimization, and security in AWS environments.

The Last Week in AWS

AWS has evolved significantly over its nearly 20-year history, with many foundational services receiving major improvements that contradict older documentation and assumptions. Key changes include EC2 instances becoming more reliable with live migration capabilities, S3 achieving read-after-write consistency, Lambda supporting longer runtimes and container images, and networking improvements like faster CloudFront deployments. Cost optimization has shifted from Reserved Instances to Savings Plans, while authentication best practices now favor IAM Identity Center over individual IAM users. These updates address previous pain points around performance, reliability, and operational complexity.

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