I started working on open source firmware: first openbios, then coreboot. The one thing that made this a job opportunity (my career is coreboot-based for about 12 years now) was that I built some rapport within the communities. These days I'm paid to work on Chrome OS firmware, which uses coreboot. Becoming the go-to person for some aspect of the project is easier for smaller projects rather than huge operations like…
when it comes to hiring, a differentiator is that you are already working on the project. not everyone contributing now is actually waiting for a job.
in one niche community i was able to get interesting jobs because i was the only one willing to move to take the job.