Update Dockerfile

Dockerfile

@@ -1,7 +1,34 @@
 FROM python:3.10-slim
+
+# Prevent python cache files
+ENV PYTHONDONTWRITEBYTECODE=1
+ENV PYTHONUNBUFFERED=1
+
+# HuggingFace model cache location
+ENV HF_HOME=/tmp/hf
+ENV TRANSFORMERS_CACHE=/tmp/hf
+ENV HF_HUB_DISABLE_TELEMETRY=1
+
 WORKDIR /app
+
+# Install system dependencies needed for RDKit / scientific stack
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    git \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy requirements first (improves Docker layer caching)
+COPY requirements.txt .
+
+# Install Python dependencies
+RUN pip install --no-cache-dir flask gunicorn \
+    && pip install --no-cache-dir -r requirements.txt
+
+# Copy application files
 COPY . .
-RUN pip install flask
-RUN pip install gunicorn -r requirements.txt
+
+# HuggingFace Spaces uses port 7860
 EXPOSE 7860
-CMD ["gunicorn", "-b", "0.0.0.0:7860", "app:app"]
+
+# --preload loads models once instead of per worker
+CMD ["gunicorn", "--preload", "-w", "1", "-b", "0.0.0.0:7860", "app:app"]