That job titles matter very much. Roles and responsibilities matter a lot more. The expectations of a "senior software engineer" at one company may have very little in common with the expectations of a role with that same title somewhere else.
I don't know the titles of most of the people I work with on a daily basis, and it doesn't impact our ability to collaborate. Hell, I don't even know the title of my manager. I've only found titles to matter when advertising a rough skill+experience level to other people, or when setting goals with my manager to "rise" within a hierarchically structured employment scheme.
When I attend a conference or other community event, I often give myself a different title depending on what I'm working on that day/week/month 😏
My official corporate title is meaningless to me and everyone else I work with.
pro-tip: if you really need a job title for marketing purposes, you can create a startup "Uber for flying fish". Fill the paperwork, incorporate in Delaware, there are people that can explain how to do it. No need to find paying customers.
Instantly you can call yourself CTO or whatever else you wish.
Not a new idea, mind you, this is what a lot of people are already doing on LinkedIn
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