Dockerfile.runpod

# LyricSync RunPod serverless worker — GPU compute (Demucs + faster-whisper).
#
# Same NVIDIA CUDA runtime base as the Modal image: it ships libcublas + cuDNN
# on the loader path, which CTranslate2 (faster-whisper) needs and which a plain
# python/debian image lacks. Build + push with scripts/build_runpod.sh.
FROM nvidia/cuda:12.4.1-cudnn-runtime-ubuntu22.04

ENV DEBIAN_FRONTEND=noninteractive \
    PIP_NO_CACHE_DIR=1 \
    PYTHONUNBUFFERED=1

# ffmpeg: decode/probe. libsndfile1: soundfile (Demucs stem write). python3/pip
# from the distro (Ubuntu 22.04 -> 3.10; align.py uses `from __future__ import
# annotations`, so the `X | None` hints are fine).
RUN apt-get update && apt-get install -y --no-install-recommends \
      ffmpeg libsndfile1 python3 python3-pip \
    && rm -rf /var/lib/apt/lists/* \
    && python3 -m pip install --upgrade pip

WORKDIR /app

# torch built for CUDA 12.4 (matches the base image). NOT the default PyPI
# wheel: that's now a CUDA 13 (+cu130) build, which RunPod's GPU driver (CUDA
# 12.8) is too old to run -- "NVIDIA driver too old". A 12.8 driver runs cu124
# fine. Install first so the project's torch pin resolves to this build.
RUN pip install torch torchaudio --index-url https://download.pytorch.org/whl/cu124

# Core lyricsync deps (NOT the api extra -- no FastAPI needed in the worker)
# plus the RunPod SDK. torch is already satisfied above.
COPY pyproject.toml README.md ./
COPY lyricsync ./lyricsync
RUN pip install "." runpod

COPY runpod_handler.py ./

# Bake weights into the image so a cold worker doesn't download them. The last
# line warms Silero VAD's torch.hub cache (vad=True is the default for music) so
# a cold worker never reaches out to GitHub for it on the first aligned request.
RUN python3 -c "from demucs.pretrained import get_model; get_model('htdemucs'); \
import stable_whisper; stable_whisper.load_faster_whisper('small', device='cpu', compute_type='int8'); \
from stable_whisper.stabilization.silero_vad import load_silero_vad_model; load_silero_vad_model()"

CMD ["python3", "-u", "runpod_handler.py"]