Obligatory legalize disclaimer: These words are mine and not Amazon's.
Software Development Engineer II
I'm not exactly sure why it's not just "Software Engineer" but at a company as large as Amazon, there are other roles that would have a lot of "Software" and "Engineer"; so "Software Development Engineer" (aka SDE) is what most would just call a "software engineer". We usually just shorthand it to "dev".
The "II" indicates a bit more of a "senior" status (though "Senior" is reserved for a much higher level).
Differences between a SDE I and SDE II roles are many, but at a high level it means dealing with more ambiguity and responsibility. An SDE I focuses on tasks and projects; an SDE II focuses on that and long-term sustainability, interacting with other teams, project design, etc. I'm to be a team leader and set the example. It's expected that I can resolve any tech ops issues and answer any senior staff's questions.
None of this is to say that an SDE I doesn't do any of that too. It's just what's the default expectation.
I was promoted to II after 2 years at Amazon, which is pretty typical. I'm shooting for III in 3 years from now or so; again, pretty typical.
All that said, there's no "level" posturing in day to day stuff. Saying "Not my job" is verboten.
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