I don't think it will be a problem to do both.

It doesn't take long to learn Julia well enough to write a Julia package that others will use. For me, that was about 3 weeks @ 10-15 hours a week, and I'm no programmer. It's a small language and it's quite readable. I'd reccomend going through the Julia manual; it doesn't take long and only requires some diligence.

The problem is the lack of packages/libraries and lots of documentation is still missing. That, and the packages that do exist with multiple contributors are still in disagreement about standards and consistency.