import-cost-core

Calculate the bundle size of imported packages in JavaScript and TypeScript with a CLI and Node.js API. Version 5.5.0, actively maintained (2025 release). Powered by esbuild and es-module-lexer for high performance — scans 50+ files in less than a second. Provides minified, gzipped, and brotli sizes; identifies tree-shakeable packages; supports budget enforcement, JSON output, ignore patterns, watch mode, and git diff for CI/CD. Works with npm, pnpm, yarn, and bun. Aims to be a drop-in replacement for the deprecated import-cost VS Code extension backend, offering more accuracy and speed than webpack-bundle-analyzer or cost-of-modules.