How can I learn about these topics? Junior self-taught dev, I read these things and kind of see what they're about, but I wouldn't know where to even start with this...
(I worked at Google with Bob in the mid-2000s. I might have interacted with him once or twice on the internal Java and Guice mailing lists, but never met him in person. He was supremely helpful and knowledgeable, and I admired him from a distance.)
Other than that, several companies (such as Uber) operating on a large scale maintain engineering blogs.