René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\\win\\async.c, line 76","articleBody":"### Version\n\nv24 LTS/default\n\n### Platform\n\n```text\n\n```\n\n### Subsystem\n\n_No response_\n\n### What steps will reproduce the bug?\n\n# Node.js process crash on build exit: `Assertion failed: !(handle->flags & UV_HANDLE_CLOSING)` on Windows\n\n## Environment Info\n\n- **OS**: Windows 11 (build local time check: 2026-07-06)\n- **Node.js Version**: v24.13.0\n- **npm Version**: 11.x (or matching Node v24 default)\n- **Framework/Tooling**: Astro `^7.0.6` with Svelte `^5.56.4` integration\n- **Libraries in play**: curtainsjs `^8.1.6`, gsap `^3.15.0`, lenis `^1.3.25`\n\n---\n\n## Description\n\nWhen running `npm run build` (which runs `astro check && astro build`), the static assets compile successfully with **0 errors and 0 warnings**. However, immediately after the compilation output shows `[build] Complete!`, the process crashes during termination with a low-level libuv assertion error.\n\n### Error Console Output\n\n```bash\ngenerating static routes \n14:11:19   ├─ /index.html (+38ms) \n14:11:19 ✓ Completed in 131ms.\n\n14:11:19 [build] ✓ Completed in 452ms.\n14:11:19 [build] 1 page(s) built in 531ms\n14:11:19 [build] Complete!\nAssertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\\win\\async.c, line 76\n```\n\n---\n\n## How to Recreate This Issue\n\nThis issue can be reproduced on any Windows system with Node.js `v24.x` using a fresh Astro template:\n\n1. **Initialize a fresh Astro project:**\n   ```bash\n   npm create astro@latest test-crash -- --template basics\n   cd test-crash\n   npm install\n   ```\n\n2. **Run the build script:**\n   ```bash\n   npm run build\n   ```\n\n3. **Verify the crash:**\n   Once the build completes and attempts to exit the process, the console will print:\n   `Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\\win\\async.c, line 76` and exit with code `1`.\n\n---\n\n## Additional Context\n\n- The issue appears to be a **use-after-close** race condition when Node.js tear-down steps close file-watchers or active handles created by Vite/Astro.\n- Since the build completes successfully, all output artifacts are generated correctly. The crash only occurs on process exit.\n- This is a known OS-specific issue for Windows runtimes inside libuv.\n\n\n### How often does it reproduce? Is there a required condition?\n\nEvery build\n\n### What is the expected behavior? Why is that the expected behavior?\n\nNo errors.\n\n### What do you see instead?\n\n`Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\\win\\async.c, line 76` and exit with code `1`.\n\n### Additional information\n\n**What steps will reproduce the bug?** section include the output of an agent, every reference/explanation is there.\n\n\u003cimg width=\"628\" height=\"140\" alt=\"Image\" src=\"https://github.com/user-attachments/assets/6d705461-bcf1-4b82-97e8-dcbabf567898\" />\n","author":{"url":"https://github.com/ostarev","@type":"Person","name":"ostarev"},"datePublished":"2026-07-06T12:38:07Z","url":"https://github.com/nodejs/node/issues/64322"}