I see these senior vs non-senior engineer contrasts pop up a lot. I’m not a huge fan of them.

It seems that there is a spectrum of skills an engineer could excel at: programming, infrastructure, managing, planning, etc. I’ve known senior engineers who only excel at a particular skill. I’ve also known senior engineers who are moderately good at many but not particularly good at one.

In my experience the only difference between a senior and non-senior is that the senior’s distribution of skills makes them more effective.

I’ve also seen senior engineers change roles laterally and become more or less effective, yet still maintain the senior title.