#architecture

The LLM security diagram you have seen a dozen times is a threat map. Read as a defence it makes you patch every box at the layer the attacker controls. The fix is one deterministic boundary the diagram leaves out, in code the model never touches.

Designing a production agent over sensitive data: no control makes the flow hole-free. You rank the layers, assume each one leaks, and stack them so no single hole reaches the data. Here is the code that does it.

A personal Bedrock-adjacent build that went through three iterations and an architecture pivot. Five lessons that map directly to production AWS AI work.

Before writing a single line of agent code, I spent a week figuring out where to run it. Here's the architecture decision that changed everything, and the Lambda limitations that forced my hand.