Fractional CTO is one of those titles that means almost nothing on its own. We've seen it cover senior architects on retainer, ex-VPs doing two days a week, sales-heavy advisors who don't write code, and full-time consultants charging Series-A salaries by the month. Some of those people would be a good hire for you. Most wouldn't.
Here are the six questions we'd ask before signing — informed by being on both sides of this engagement more times than is healthy. Asked together, they sort the room quickly.
1. What does a typical week look like for you?
If the answer is mostly meetings, decks, and Slack — be careful. The good operators spend at least a few hours a week in your code, your cloud, or your data. Not because they're shipping production work, but because they need ground truth to make decisions you can defend.
2. Show me a decision you got wrong.
An honest one. With a real consequence. Senior people have a stack of these and will share them in concrete detail. People who are mostly senior on the title page will go vague, deflect, or pivot to a generic lesson. Pay attention to who picks the easy answer.
3. Who would I call when you go on holiday?
A real fractional engagement has bench. One person can't be senior architect, on-call lead, hiring partner, and incident commander every week of the year. Ask who the second name on the account is and how the handover works. If there isn't one, you're hiring a single point of failure.
4. What's the smallest thing you'd change in our setup, and why?
Asked after they've seen 30 minutes of your stack. The strong answer is small, specific, and focused on a future cost they can predict — not a sweeping rewrite. The weak answer is a pitch for a six-month engagement they happen to sell.
5. How do you bill, and what would make you walk away?
Two questions in one. The pricing answer tells you whether they price at cost, market rate, or something more theatrical. The walk-away answer tells you whether they have a real bar — a senior who'll never walk away is a senior whose incentives aren't aligned with yours.
6. What would you tell my next investor about us?
Specific to the engagement, this one. They've worked with you for a couple of months. Could they walk into a partner pitch and answer the technical reference call without prepping? If not, they don't know you well enough yet — or they don't actually want to. Either is information.
A short note on price
We don't think rate is the most useful filter. There are good fractional CTOs at every band, and there are people charging eye-watering numbers who are buying you a brand more than expertise. Use rate as a sanity check on whether the engagement fits your runway, not as a proxy for quality.
If you want to see how we'd answer all six on a real engagement, the discovery call is the place.