Explore a conference talk that delves into managing Airbnb's massive JVM monorepo containing tens of millions of lines of Java, Kotlin, and Scala code. Learn practical solutions for handling complex challenges in large-scale development, including implementing Remote Persistent Workers for RBE, enabling cross-platform builds across Mac and Linux systems with universal binaries, managing multiple language versions and runtime environments, optimizing compilation processes, and generating bytecode directly when conventional optimizations fall short. Gain insights from both successful implementations and failed attempts while discovering strategies for maintaining and scaling large monorepo architectures in a multi-language JVM environment.