BUN RUNTIME CORE REWRITTEN IN RUST

Bun, the all-in-one JavaScript runtime and toolkit, has completed a significant architectural overhaul. The merged PR #30412 replaces the Zig-based core with a Rust implementation, a shift that affects how Bun handles JavaScript execution. The rewrite addresses longstanding technical debt and aims to improve maintainability and performance. Rust's type system and memory safety features provide stronger guarantees compared to Zig, which could reduce certain classes of bugs. Bun was initially built in Zig for speed and low-level control. The shift to Rust represents a pragmatic choice balancing performance with developer experience and ecosystem maturity. The change has generated significant discussion among developers, with 389 comments on Hacker News highlighting both enthusiasm and technical concerns. The merger marks a major milestone for the project, though full rollout and stabilization will require additional testing and refinement across Bun's feature set.