Blocking file I/O inside async function in video presentation node

[Joaquinriosheredia]

Hi,

I've been running python-vibe-guard against open source Python projects
to validate async runtime detection rules.

Found a potential issue in:
surfsense_backend/app/agents/video_presentation/nodes.py line 140

response = await aspeech(**kwargs)
with open(chunk_path, "wb") as f:
    f.write(response.content)

open() and f.write() are synchronous calls inside an async function.
Under concurrent load, this blocks the event loop for the duration of
each file write, serializing all concurrent connections through a single
bottleneck.

Consider using aiofiles as an async alternative:

import aiofiles
async with aiofiles.open(chunk_path, "wb") as f:
    await f.write(response.content)

Tool used: python-vibe-guard —
AST-based runtime anti-pattern scanner validated on 250 real repositories.