babel-plugin-transform-define

A Babel plugin for compile-time replacement of identifiers, member expressions, and typeof statements, similar to Webpack's DefinePlugin. The current stable version is 2.1.4 (released 2024-12-12), with a slow, maintenance-focused release cadence. Unlike Webpack's DefinePlugin which operates at the bundler level, this plugin works at the Babel transpilation stage, making it useful for library authors who want to define compile-time constants without a bundler. Key differentiator: supports replacing typeof expressions (e.g., "typeof window": "object") and member expressions (e.g., "process.env.NODE_ENV": "production"). Notable changes: v2.1.3 avoids replacing object keys to prevent bugs; v2.1.4 also prevents object property replacement. Maintenance status is stable, with no active feature development but continued bug/security fixes.