The Portland startup where I work just hired 3 jr. devs. Our goal was 2 seniors and 2 juniors but we didn't get any viable senior candidates. Most candidates were eliminated at the code challenge stage. So that'd be my tip: if you have to complete a code challenge, make sure it's the best code you've ever written. Even if it's a trivial task, things like full test coverage and demonstrating that you know some OOP best practices will give you a better chance at an interview.

The two bootcamp grads we hired had much stronger skills than most of their peers. I had conversations with their instructors and, indeed, they said that these guys were top of the class.

Also note that while senior devs are hard to find, competition is fierce at the junior level. We relocated one from Boston and the other had done his bootcamp in Chicago.