VoxCPM2 ran only in-process, so using it meant installing voxcpm, and a
torch of its choosing, into the app's own environment. It now has a
one-click install into DATA_DIR/engines/voxcpm2/.venv and a self-contained
sidecar (engines/voxcpm2_subprocess) that imports nothing from the app.
tts_backend resolves the voxcpm2 id to the sidecar once that venv exists,
and to the in-process class otherwise, so an existing pip install keeps
working.
voxcpm leaves torch unpinned. Resolved with the CUDA index, that paired
PyPI's newest torch (CPU-only on Windows) with a +cu128 torchaudio, and
uv's --torch-backend fell back to voxcpm 1.5.0 on Windows. A new
torch_pins spec field pins the pair, and the host picks the build: +cu128
on CUDA hosts, +cpu on other Windows and Linux hosts, plain on macOS. Each
was resolved with voxcpm==2.0.3. Not offered on Intel Macs, where torch
2.11 has no build.
The parent keeps the reference-clip preparation and the trailing-silence
trim, so output matches the in-process engine. The sidecar retries a
transient weight download like the app's loader does.
Palash Debnath
21105b24a5
