That should literally never be the case for a developer though.
You can always be improving the documentation, increasing the test coverage, optimizing for speed/bandwidth/complexity/some other metric you've measured, working out how to measure something, learning new tools or tech that could be applied to a project, working on a spike for some future feature that needs upfront research.
If you see those things as "the boring bits" that you don't want to do then you're not a developer. You're a hacker. You want to hack what you see as the fun stuff rather than developing complete, robust applications that can ship. That's fine, and loads of fun, but no one will pay you to that. You don't get a role like that unless you're some sort of programming savant on a par with the likes of John Carmack or Fabrice Bellard - someone has proven they can invent amazing things by being left to their own devices. Unfortunately, you really need to prove yourself first before you can land a gig like that. If it was easy we'd all have done it.