Kiro is created by an AWS team, and originates from AWS expertise. We are using Kiro internally as one of our recommended tools for development within AWS (and Amazon). So Kiro is an official AWS product, however, we are also keeping it slightly separated from the rest of core AWS.

For example, you can use Kiro without having any AWS account at all. Kiro has social login through Google and GitHub. Basically, Kiro is backed by AWS, but is it's own standalone product, and we hope to see it grow and appeal to a broader audience than just AWS customers.