Submit HN: How do I progress from junior to mid-level developer?

I've been a junior developer at a large Bay Area company for slightly more than 2 years. I've implemented basic features and I've fixed lots of bugs. I've read most of the standard "required reading" textbooks such as Code Complete, Pragmatic Programmer, Clean Code, Refactoring, etc. I'm trying to learn more about the domain I work in (security).

But that's about it. I don't feel like I've become a significantly better developer between years 1 to 2. Year 0-1 was filled with a tremendous amount of learning, 1-2 seemed like a plateau with minimal growth. I don't see a bright future for myself at this company because I'm polishing my resume and didn't add many new skills. My team essentially maintains a legacy system. Bugs are never-ending, but I don't want to do this for the rest of my career.

I'm actively looking for another job, but I seem to be "too junior" for mid-level positions, but too experienced for "new grad/junior" positions. I don't know what to do next.