That’s right. I know I was thrown off by large projects earlier in my career. The more you learn the stronger you get at understanding and packaging/setting-aside larger and larger pieces of a project. Bigger projects stress this ability in new ways. I think I lost a job in 2016 because I couldn’t stretch my brain around something bigger, at a small business with maybe 14 devs.
This might be a bad way to communicate this, and I think I’m taking this in a weird direction, but: I’ll use the Mozilla project as an example of a large project, though I’ve never looked at its source.
Suppose you were in an interview, and due to the specifics you are expected to be fast and fluent with the same technologies used in the Mozilla project, though you’ve never looked at the source before. Given a machine with the source already checked out and open in an IDE, you have one hour to read through the source and familiarize yourself with it, so you can answer questions about how you would approach adding features or test coverage.
What I want to know is: how high does your heart rate go? Does it go up just a little, as expected for a high stakes situation? Or does it go up a lot, because you honestly have no idea how much another dev in your situation would be expected to accomplish, so you have no clue what “good enough” looks like?
This is a crappy example because no interviewer could ever actually use this metric. But I’d say if it goes up a lot, for the reason I gave, you might not be ready for senior. And by this metric, it might not ever be possible to grow to “senior” without working at a company with large multi-team projects. But I think that’s accurate.
(Edit: yes, sorry, Software Development Engineer. I think that’s a protected term in the US, in Texas and California at least, but anywhere else in the US you don’t need to pass an engineering board exam to use that title.)