I was looking at the execution history for a Step Functions state machine that is triggered daily by an EventBridge Scheduler schedule. The execution names caught my eye — they look like UUIDs, they're not UUIDv7, but there's clearly a pattern. It got me excited in the same way that noticing AWS access key IDs were similarly-formatted back in 2020. So of course I had to dig in.
I've been writing software for 25 years, and been getting paid for the last 20. My AWS account will be turning 18 this September, and it should be quite the celebration. If I may toot my own horn: I've got pretty good at writing and deploying software in that time - to the point that you're actually spending your time reading this blog. All this, and the release of Opus 4.5 in November 2025 hit me like a tonne of bricks. My value-add (as I knew it) would soon be over.
AWS principal tags are useful for fine-grained access control. As an organisation administrator, you can craft service control policies (SCPs) that only allow tagged roles to call sensitive APIs. The problem then becomes: how do you guarantee that the tags are legitimate? This is where resource control policies (RCPs) come in handy - I provide a demonstration of them in this blog post, and an example of what you can achieve with the trustworthy tags in place.