René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"`import \"typescript\"` slower than `require(\"typescript\")` due to `cjs-module-lexer` overhead","articleBody":"### Version\n\n- Node.js v24.8.0\n- Node.js v22.18.0\n\n### Platform\n\nObserved on macOS (x64), but likely reproducible on other platforms.\n\n### Description\n\nWhen loading `typescript`, using `import` is ~100ms slower than `require`.\n\nThis seems to come from the `cjs-module-lexer` step Node.js runs for CommonJS packages. Since `typescript` itself is CommonJS, `require` avoids the overhead and is noticeably faster.\n\n\u003cimg width=\"2368\" height=\"1322\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/d0ec96bb-4b96-4222-843e-e45bd9138f96\" /\u003e\n\n### Reproduction\n\n\u003e https://github.com/chenjiahan/nodejs-repro-require-import-typescript\n\n```js\n// import.mjs\nimport typescript from \"typescript\";\n\nconsole.log(typescript);\n\n// require.cjs\nconst typescript = require(\"typescript\");\n\nconsole.log(typescript);\n```\n\n**Example results (macOS, Node.js v24.8.0):**\n\n```bash\n# ~200ms\ntime node ./import.mjs\n\n# ~100ms\ntime node ./require.cjs\n```\n\n### Ref\n\n* https://x.com/matteocollina/status/1968303799271047230 @mcollina \n","author":{"url":"https://github.com/chenjiahan","@type":"Person","name":"chenjiahan"},"datePublished":"2025-09-17T13:45:47.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":10},"url":"https://github.com/59913/node/issues/59913"}