My take is that the difference between junior / mid / senior / principle / CTO is the following question: At what scope are you taking responsibility? A junio

My take is that the difference between junior / mid / senior / principle / CTO is the following question: At what scope are you taking responsibility? A junior can take responsibility to take a completely described specification and turn it into code. Eg, "We need a button on the page which looks like this: (mockup). When clicked, it should do this." A senior can take responsibility for broader / more ambiguous problems. For example: "We're getting sporadic reports from users that they can't fill in this web form. But we can't reproduce it - every time we ask them to show us, everything works." / "The website just feels slow". Or: "The web server crashed again last night! That's the third time this month. How do we make this problem go away?" As you keep "going up", the solutions increasingly involve subtle judgement (of the team and the customers) and interacting with other people. "Hey Jenny - I've been looking into a reported bug. I talked to a couple of our users about it. Part of the problem is this particular UX flow. I think it needs another pass. How full is your plate?" / "Ideally we'd scale up the team. Our biggest bottleneck is frontend iOS development. Lets hire 2 more devs. I'll talk to a couple recruiters and get the process started." With this sort of perspective in mind, it gets much easier to judge the seniority of someone. Forget their job title, past or present. The author is right: Thats more signal than noise these days. In an interview, ask them to tell the story of some problems they've faced in their last role. Press for details on how the issue was communicated to them, and what was difficult / rewarding. Juniors will talk about tickets they closed, or tell you a story about a failing test case they were assigned by their lead that they fixed. Seniors will talk about something ambiguous and long running, or how they speced out a problem. Or about a long running issue they found & fixed off their own initiative. CTO level people will talk about hiring, or one time they corrected something that was going wrong in the team's culture. Its pretty clear. Was it a more ambiguous problem? Was the scope broad? Did they take the initiative themselves? Did solving it involve judgement in a broad range of areas (eg technical, social, UX, etc)? All of those things demonstrate that the person is acting at a more senior level. I use the same approach when coaching people at work. Lots of people are capable of operating at a higher level, they just need the right set of challenges and often the right push to take initiative and start stretching themselves. (And plenty of people, sadly, are the opposite.)