[danielovich]

One problem is that people think about seniority as expert level in something.

In my terminology, when you are a senior you need to be a near expert in whatever you call yourself a senior within.

If that's .NET/C# like the author refers to, you must know how all (the esoteric) features of the language (e.g C#) behaves, you must know IL, WinDBG for advanced debugging and the things along those lines.

So many developers claim something that they are absolutely not, which is experts or senior in a technology.

It's IMO much harder to become an expert in something than to learn a subset of a set of technologies. Much harder actually.

[james_s_tayler]

I would class your definition as expert rather than senior. It's a level above what I'd expect.

Then again seniority has many dimensions. I often see a lot of senior devs who have mid level skills or mindset but they have become domain experts or experts in the product and seniority is conferred that way. I don't necessarily think that is wrong or undeserving either. I guess if we are talking absent any business/domain knowledge then seniority is judged more closely off raw technical familiarity. For me it's about system design/architecture. Having a strong set of principles that guide your decisions etc.