Intro I recently cracked open a copy of *OS Internals Volume 1 and wanted to follow along with some of the system library examples show in the book. I’m a huge fan of Ghidra for my reverse engineering, so I fired it up, created a new project, and navigated to /usr/lib to find… no libSystem.B.dyld present. “How annoying” I thought to myself, “they must have moved the system libraries since the book came out”. The book was published in 2019, and MacOS has a storied history of moving things around, so this felt like the most reasonable explanation. Striving to be the self-sufficient reverse engineer, I ran the following otool command to find the system library: