Just a bit of general advice based on my experience. If you can find a job that asks specifically for Julia that’s great, but if you want to find jobs related to machine learning, optimization and data science and have more options, Python should figure most prominently on your resume, then, on the interview, you can (diplomatically) say “oh I actually mostly use Julia, it’s way better than Python for the following reasons…”. Open-minded hiring managers may be impressed with this, even if they wouldn’t touch a resume that only says Julia. At that point you’d have to feel out whether they’d actually let you use Julia. Organizations with more open cultures will likely embrace this, but many will take the attitude “Everything we already have is written in Python, therefore using anything other than Python is blasphemy” so watch out for those. It’s a pretty good filter, as presumably the culture at those latter types of places is unpleasant for all sorts of reasons.
Of course, your mileage may vary. This is based on my own experiences and those of friends, though I seemingly had to overcome a significant stigma having come directly out of academia with a PhD in physics. If your background is more appetizing in private industry, you may have a significantly easier go of it, and none of this may even matter.
It’s really nice to hear of jobs at national labs that are looking specifically with people with Julia experience. Having worked at a national lab for years as a student, I can say that the culture and environment there was wonderful and it doesn’t surprise me to see them leading the way in this sort of thing.