Rust and Kotlin Power JetBrains Fleet's Sub-Second Code Indexing Engine

JetBrains Fleet achieves sub-second code indexing for million-line projects, cutting memory overhead by 40% compared to IntelliJ IDEA—a breakthrough that could reshape development tool performance expectations. The Rust-Kotlin hybrid architecture demonstrates how systems programming languages can dramatically accelerate traditionally CPU-bound operations in IDEs. With plans to open-source the indexing core in Q3 2025, this approach could influence the entire development tools ecosystem.