how does it compare to AWS' Application composer?
InfraCopilot is more akin to Wolfram Alpha, in the sense that it has an intelligence/understanding of architecture. You can use high level design to describe your intent and requirements/constraints, and it will deterministically implement it (this isn't LLMs or ChatGPT). When you attempt low level changes, it will validate that they maintain correctness, because it has an understanding of impacts.
When you reshape elements, it has the understanding of follow-on effects, and how to propagate them into the rest of the architecture, all while staying valid.
[0] https://aws.amazon.com/application-composer/