In a tech-driven startup, hiring a great CTO is the equivalent of scoring a great funding round. A proper Chief Technology Officer will save you thousands of hours and headaches by attracting the best technical people for the job, by being extremely demanding technically and by making you comfortable with taking strategic roadmap decisions.

The 5 responsibilities and corresponding interview questions I see for a CTO position are:

1. Develop a Technology Vision

  • what do you think is the product we are trying to build? how do you see it working?
  • actually the product we're trying to build is X. It works like Y. how do you break down this product into autonomous parts? How do you create a technology vision for this idea? What's a "stack" for it supposed to look like? Why? Which technologies and frameworks would you see as possibilities for building it? Why?
  • what adjacent opportunities can this platform tackle? Which opportunities can't it tackle? 
  • what similar companies have you helped in a similar position? How similar was the goal in terms of complexity and medium? When you joined, what was the development level, and what was it when you left? Compare the stacks. 
  • what do you think Company Xs technology vision is? What do you think they are doing back in there?
  • what technologies are you familiar with? What about X? Are you full-stack, hands-on?
  • what's your relationship with founders like? 

2. Manage Development Operations

  • how do you hire a great technical developer? How many developers have you hired in the past? Can you name a few great ones? How much does a great developer, engineer, X cost?
  • How much freedom do you give devs? Are developers doing development according to a specification, or interpreting? Are they responsible for quality? Describe the whole development cycle, from end to end, including owners and participants.
  • how many people have you managed? Was any of these teams similar in vision to ours? How much did the teams and systems grow in your tenure? how do you manage technical product developers on a daily basis?
  • when and how do you fire a developer? How do you evaluate them in general?
  • strip down our envisioned product into basic features and building blocks. What would you build in the very first version? How would you roll out new functionality? How incrementally would you improve it?
  • which tools do you use to organize your team? How frequently do you synch up? 
  • what's a nice budget for us? Can you work with half? What if we can't hire an X?

3. Manage and improve infrastructure

  • where is the friction in our business model in terms of infrastructure capacity? what is an appropriate infrastructure for it? 
  • Are you experienced in managing local, physical servers? Remote servers? IaaS? Please describe
  • how do you monitor our infrastructure and the health of our systems? What about security?
  • how do you manage access? And licenses?
  • how expensive is it to scale? Give one example
  • what's your policy on test devices?

4. Establish yourself as an External Technologist

  • which technologies do you follow more closely? how well known are you in their communities? How close are you to the leader? What are your major software / hardware contributions? What's your major contribution in StackExchange/ StackOverflow/ X?
  • how many people follow you? How many people do you follow? Who? Why?
  • which companies and organizations are you affiliated with? What's your relationship with them? Who do you know at Apple/ Google/ Amazon/ X?
  • what's your stance on open source and open company projects?

5. Big Think

  • what's happening to the internet, production, engineering, technology?
  • which things do you think will become important in the next 5 years? What's is the impact you'd say those things will have on our product? Users? Revenue? Costs?
  • what is the biggest global technology transition you've witnessed and in which you had some stakes? How did you surf the wave?
  • what's was the biggest product change you've been a part of? What motivated it?
  • what are your grand ideas for this company in terms of technology? If you had to make a bold bet, what would it be?

Now, if you're interviewing a great CTO and you have the money to afford him or her, you can be sure that they'll be way too technical for you to understand all the nuances and quality of the responses. Unless you are very technical as well, it will be hard to get everything. You can trust his public status (4) as a great proxy, as the internet of technologists is a ruthless meritocracy. For 1, 2, 3 and 5 you should make sure candidates proficient enough to make you understand why they are giving you those responses. They should be able to simplify those answers to the level you want, by breaking them down and making analogies if necessary. This clear communication is vital to build trust and rapport when an employee and colleague is extremely technical.

Finally, it's extremely important to triple check all recommendations. As with any other hire.