How Expensify achieves extreme concurrency with NUMA balancing

I had some free time this holiday season and wrote up a blog post about how we use NUMA balancing on our 384-CPU, 6TB monster servers to keep the site humming reliably (and some of the challenges we've had to overcome). It's pretty low level, but I found there wasn't a lot of good info on how to optimize for high core-count servers, so I thought I'd share some experience. Enjoy!