Builds the systems that put models into production and keeps them there.
Why this one is hard to judge
A demo proves nothing. What matters is what they did when it failed under real load.
What to ask for
Ask for a system they built that is still running in production today.
Ask what happens in their system when a model call fails or times out.
Ask for the cost per request of something they shipped, and how they reduced it.
Ask them to describe a bug that only showed up after real users touched it.
The mistake most hirers make
Hirers judge candidates on how well they can explain a model, not on how they handle the mundane parts around it. The interesting work is in retries, logging and fallbacks, not in the prompt. Someone who only demos a notebook has not built anything a business can rely on.
What good looks like after 90 days
A working feature in production, not a demo, with basic monitoring around it. At least one incident handled calmly, with a clear account of what went wrong. Other engineers can read their code without asking them what it does.
How we assess it
Against a rubric that is published in full, on evidence the practitioner supplies and a reviewer checks. Where something has not been verified, the profile says so.