Fixing shit is not a task of an engineer, but a technician.
Why do you think engineers don't or shouldn't fix things?
Isn't the very idea of designing a system: solving a problem, and isn't problem solving synonymous with "fixing a problem".
One can choose to implement various formal and rigorous methods throughout a process, but at the end of the day it's all the same activity.
I'd have just been a 'technician' to you but IMO: it involved all the same skills as if I'd have designed it myself. You still need to know what all the code does well enough to have written it and have the skills to improve it. So I'm not sure the distinction really matters here.