Node + tsx "__name is not a function" crash

Summary

Running Moltbot via Node with tsx fails at startup with:

[moltbot] 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

This began after switching dev scripts from Bun to tsx (commit 2871657e, 2026-01-06). The same runtime path worked with Bun.

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)

Repro (Node-only)

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

Minimal repro in repo

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

Node version check

Node 25.3.0: fails
Node 22.22.0 (Homebrew node@22): fails
Node 24: not installed here yet; needs verification

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, which implies 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.

Regression history

2871657e (2026-01-06): scripts changed from Bun to tsx to make Bun optional.
Before that (Bun path), moltbot status and gateway:watch worked.

Workarounds

Use Bun for dev scripts (current temporary revert).

Use Node + tsc watch, then run compiled output:

pnpm exec tsc --watch --preserveWatchOutput
node --watch dist/entry.js status

Confirmed locally: pnpm exec tsc -p tsconfig.json + node dist/entry.js status works on Node 25.
Disable esbuild keepNames in the TS loader if possible (prevents __name helper insertion); tsx does not currently expose this.
Test Node LTS (22/24) with tsx to see if the issue is Node 25–specific.

References

Next steps

Repro on Node 22/24 to confirm Node 25 regression.
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.

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