I may be a submitter this year, if I can get my thoughts together and work says it’s ok. I did present at vBSDCon in September on a security-relevant topic (FreeBSD kernel RNG). I assume a room full of OS developers is a different audience, but it was my first “stand up in front of more than 4 people” type presentation since college about 12 years ago.
What helped me was interacting with people likely to be in my talk beforehand so that there were more friendly faces in the audience. It helped that many people I’d known online for 10+ years, but this was the first time meeting in person. Also, trying to keep domain-specific language to a minimum and explain. If the audience disengages, i’m fairly sure most good speakers can tell. Just because you work in a specific niche doesn’t mean everyone in attendance has all the background, even if they are experts in adjacent areas. Keep in mind people that are in your talk are there to learn, especially if there are competing tracks and they chose yours.