Dockerfile

# ── Stage 1: build deps ──────────────────────────────────────────────
FROM python:3.11-slim AS builder

WORKDIR /app

# System deps for building wheels (numpy, torch, etc.)
RUN apt-get update && \
    apt-get install -y --no-install-recommends gcc g++ && \
    rm -rf /var/lib/apt/lists/*

COPY requirements.txt .

# Install CPU-only PyTorch first to keep the image small, then the rest
RUN pip install --no-cache-dir --prefix=/install \
        torch --index-url https://download.pytorch.org/whl/cpu && \
    pip install --no-cache-dir --prefix=/install -r requirements.txt

# ── Stage 2: runtime ────────────────────────────────────────────────
FROM python:3.11-slim

WORKDIR /app

# Copy installed packages from builder
COPY --from=builder /install /usr/local

# Copy application code
COPY . .

# Expose the default uvicorn port
EXPOSE 8000

# Run the FastAPI app
CMD ["uvicorn", "API:app", "--host", "0.0.0.0", "--port", "8000"]