> As a lead or principle, I describe what I do as being a "fire-and-forget resource". I build everything myself and don't require supervision. I will deliver regardless and am also able to justify my decisions. People seem to be happy so far.

Terminology is subjective of course, but:

I would also expect the above from a "senior" developer.

I would expect a "lead" developer to additionally be involved in leading a team and coordinating work within that team. (either from a project, people or tech perspective, or all/both).

I would expect a "principle" developer to be working at a higher level coordinating work between multiple teams and making architectural decisions that cut across the whole org or a large subsection of it at a larger company.

I think it depends on the complexity of what you're building. If it's something very novel or something that requires a lot of domain or technical expertise, then you might need a principal engineer to be the point person to figure out how to even build it, or build it right. Some problems are best solved by a single person with the right skills.

Some career ladders allow for this, others are more rigid about the size of team you need to be directly leading .

I think this is the appropriate answer. In my experience as Staff engineer, the tasks I was best suited to were the nebulously defined "the customer needs X" where X cross cut a lot of domains and required input from a variety of people that would be affected by that feature X. This usually meant that I'd have to get them all together at some point and find a way to satisfy all their contradictory needs before even coming up with what the real task definition of X was.

That's generally more than you'd expect from a typical Senior Engineer.

This gets tough. My company also loosely views Senior as the pinnacle of technical achievement with Lead and Principal engineers essentially being much higher level with no direct reports, but still doing policy, stakeholder, and political activities. Recently, some have pointed out the flaws in such a system as it leaves out the potential for promoting and giving a pay raise to senior staff that have continued making themselves far more valuable, but don't want to be capped or go into politics. There needs to be a path for someone who is just beast on the technical side and can be brought out to solve any problem. If that person is an order of magnitude more knowledgeable than your seniors, then they deserve to be distinguished as such. Our competitors that have figured this out have titles to better reflect this reality.

Those are great points to consider, thank you

> Not intended to quibble, but to me that smacks of the dreaded "mid-level management" tier.

Reminds me of the classic: https://www.ribbonfarm.com/the-gervais-principle/