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Node + tsx “__name is not a function” crash

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Summary

[fased] Failed to start CLI: TypeError: __name is not a function
    at createSubsystemLogger (.../src/logging/subsystem.ts:203:25)
    at .../src/agents/auth-profiles/constants.ts:25:20

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Environment

• Node: v25.x (observed on v25.3.0)
• tsx: 4.21.0
• OS: macOS (repro also likely on other platforms that run Node 25)

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Repro (Node-only)

# in repo root
node --version
pnpm install
node --import tsx src/entry.ts status

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Minimal repro in repo

node --import tsx scripts/repro/tsx-name-repro.ts

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Node version check

• Node 25.3.0: fails
• Node 22.22.0 (Homebrew node@22): fails
• Node 24: needs verification on the local machine where the crash appears

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Notes / hypothesis

• tsx uses esbuild to transform TS/ESM. esbuild’s keepNames emits a __name helper and wraps function definitions with __name(...).
• The crash indicates __name exists but is not a function at runtime. That usually means the helper is missing or overwritten for this module in the Node 25 loader path.
• Similar __name helper issues have been reported in other esbuild consumers when the helper is missing or rewritten.

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Workarounds

• Use the normal runner scripts instead of direct node --import tsx:
  pnpm fased status
  pnpm gateway:watch
  
• Or build first, then run compiled output:
  pnpm build:fast
  node --watch fased.mjs status
  
• Confirmed locally: compiled output plus node fased.mjs status works on Node 25.
• Disable esbuild keepNames in the TS loader if possible. That prevents __name helper insertion; tsx does not currently expose this.
• Test Node LTS with tsx to confirm whether the issue is local to a specific Node/loader combination.

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References

• https://opennext.js.org/cloudflare/howtos/keep_names
• https://esbuild.github.io/api/#keep-names
• https://github.com/evanw/esbuild/issues/1031

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Next steps

• Repro on the supported Node LTS line and the newest local Node version.
• Test tsx nightly or pin to earlier version if a known regression exists.
• If reproduces on Node LTS, file a minimal repro upstream with the __name stack trace.