I Can't Believe Rust is Replacing Java

XAI completely rewrote X's recommendation algorithm, replacing dozens of Java/Scala microservices with four Rust components and a Grok-based transformer. The old system used hand-engineered features and explicit weights across interconnected services, while the new architecture moves intelligence into an ML model with Rust handling orchestration. The shift addresses JVM garbage collection issues for sub-millisecond latency requirements and reflects a broader industry trend of using Rust for performance-critical infrastructure alongside AI-driven systems.