Dockerfile

# syntax=docker/dockerfile:1.7

# Builder stage: install Python deps once and copy only the wheels we need.
FROM python:3.12-slim AS builder
WORKDIR /app
ENV PIP_NO_CACHE_DIR=1
COPY requirements.txt .
RUN --mount=type=cache,target=/root/.cache/pip \
    pip install --prefix=/install -r requirements.txt

# Runtime stage: lean image with only runtime files and installed deps.
FROM python:3.12-slim AS runtime
WORKDIR /app
ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED=1
ENV PYTHONPATH=/app

# Copy preinstalled dependencies from builder image.
COPY --from=builder /install /usr/local

# Copy application source last to maximize cache hits.
COPY ./src ./src

CMD ["uvicorn", "src.main:app", "--host", "0.0.0.0", "--port", "8000"]