Windows: hunk diff auto-launches daemon with invalid Bun argv

[qqhhhh]

Summary

On Windows x64 with hunkdiff@0.16.0, hunk.cmd diff opens the TUI correctly, but the live session daemon is not reachable. As a result, hunk.cmd session list --json hangs / never returns a session unless I manually start hunk.cmd daemon serve first.

The root cause appears to be that the auto-launched daemon command receives an extra B:/~BUN/root/hunk.exe argument.

Environment

• OS: Windows x64
• Shells tested:
  • Windows PowerShell 5.1
  • PowerShell 7.6.3
• Node: v24.16.0
• npm: 11.13.0
• hunkdiff: 0.16.0
• Install method:

npm.cmd install -g hunkdiff

Steps to reproduce

From a Git repository:

hunk.cmd diff

The TUI opens successfully.

In another terminal:

hunk.cmd session list --json

Expected: returns the live Hunk session.

Actual: it does not return a usable session. On my machine it hangs until manually killed.

Manual daemon workaround

If I manually start the daemon first:

hunk.cmd daemon serve

It prints:

Session broker API listening on http://127.0.0.1:47657/session-api
Session broker websocket listening on ws://127.0.0.1:47657/session

Then hunk.cmd diff registers successfully, and:

hunk.cmd session list --json

returns the live session.

Evidence

After launching only:

hunk.cmd diff

Hunk writes daemon metadata to:

%TEMP%\hunk-mcp\daemon-127-0-0-1-47657.json

The metadata contains:

{
  "command": "C:\\Users\\Administrator\\AppData\\Roaming\\npm\\node_modules\\hunkdiff\\node_modules\\hunkdiff-windows-x64\\bin\\hunk.exe",
  "args": [
    "B:/~BUN/root/hunk.exe",
    "daemon",
    "serve"
  ]
}

Running that command manually fails:

& "C:\Users\Administrator\AppData\Roaming\npm\node_modules\hunkdiff\node_modules\hunkdiff-windows-x64\bin\hunk.exe" "B:/~BUN/root/hunk.exe" daemon serve --help

Output:

hunk: Unknown command: B:/~BUN/root/hunk.exe

But running without the extra B:/~BUN/root/hunk.exe argument works:

& "C:\Users\Administrator\AppData\Roaming\npm\node_modules\hunkdiff\node_modules\hunkdiff-windows-x64\bin\hunk.exe" daemon serve --help

Output:

Usage: hunk daemon serve

Run the local Hunk session daemon and websocket session broker.

Notes

I found a related closed issue, #406, about hunk session * hanging indefinitely when the daemon is not running on Windows. This report is more specific: the TUI appears to try to auto-launch the daemon, but the generated daemon launch metadata includes an extra Bun virtual root argument.

Suspected cause

The Windows prebuilt binary / Bun-packaged executable seems to compute the daemon launch command incorrectly. It appears to treat B:/~BUN/root/hunk.exe as an entrypoint argument and passes it through to hunk.exe.

Possibly related code area: session broker daemon launcher / argv handling for packaged Bun executables on Windows.

Expected behavior

When hunk.cmd diff starts the TUI, it should auto-launch/connect to the session broker daemon with an equivalent of:

hunk.exe daemon serve

not:

hunk.exe B:/~BUN/root/hunk.exe daemon serve

[benvinegar]

Fixed by #507 — the launcher now recognizes Bun's Windows virtual path (B:\~BUN\...) and relaunches the daemon via the real binary with clean arguments. The fix is covered by unit tests matching the exact argv shape from your report, but we couldn't exercise it on real Windows hardware — if you could re-test hunk diff + hunk session list --json once the next release is out, a confirmation here would be appreciated.