Adding external engineers directly into your existing team and process, under your technical management, rather than handing a scope to a vendor to deliver separately.
It fits when you know what to build and lack capacity or a specific skill. You keep architectural control; what you buy is throughput, not a delivery promise.
We embed engineers into your rituals, repository, and review process from week one, and we expect them to be managed as your team members — split loyalty is what makes this model fail.