JSIR: A High-Level IR for JavaScript from Google

Google has open sourced JSIR, a new tool and proposed industry-standard Intermediate Representation (IR) for JavaScript. Unlike an Abstract Syntax Tree (AST), which describes what code looks like, an IR focuses on what the code actually does, enabling deeper analysis and more advanced code transformations.

Already in use at Google for internal analysis and code transformation tasks, JSIR aims to become a foundational standard for the broader JavaScript ecosystem. The tool is designed to help developers, tool authors, and researchers better understand, optimize, and refactor JavaScript code at a semantic level.

This move could pave the way for more powerful static analysis, improved tooling, and greater interoperability across JavaScript projects, marking a significant step forward in the evolution of JavaScript development.