fix: failed to solve: process /bin/sh -c pip install --no-cache-dir -r requirements.txt did not complete successfully

Dockerfile

@@ -1,34 +1,40 @@
-FROM python:3.11-slim
+# ── Stage 1: build ───────────────────────────────────────────────────────────
+# Compiles native extensions (ckzg, asyncpg, cryptography) so the final image
+# only carries the compiled .so files, not the build toolchain.
+FROM python:3.11-slim AS builder
 
-# System deps needed for native extensions:
-#   gcc, libpq-dev  → asyncpg (Postgres driver)
-#   libffi-dev      → cryptography
-#   build-essential → general C compilation fallback
-#   curl            → healthcheck probe
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    gcc build-essential libpq-dev libffi-dev curl \
+    gcc build-essential cmake libpq-dev libffi-dev \
     && rm -rf /var/lib/apt/lists/*
 
-WORKDIR /app
+WORKDIR /build
 
-# Upgrade pip + install wheel first so pre-built wheels are preferred
 RUN pip install --no-cache-dir --upgrade pip wheel setuptools
 
-# Install Python deps (separate layer for cache efficiency)
 COPY requirements.txt .
-RUN pip install --no-cache-dir -r requirements.txt
+RUN pip install --no-cache-dir --prefix=/install -r requirements.txt
 
-# App source
+
+# ── Stage 2: runtime ─────────────────────────────────────────────────────────
+FROM python:3.11-slim
+
+# Only runtime shared libs needed (libpq for asyncpg, libgomp for numpy if used)
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    libpq5 curl \
+    && rm -rf /var/lib/apt/lists/*
+
+# Copy compiled packages from builder
+COPY --from=builder /install /usr/local
+
+WORKDIR /app
 COPY . .
 
-# Make entrypoint executable
 RUN chmod +x entrypoint.sh
 
-# Non-root user for security
+# Non-root user
 RUN useradd -m appuser && chown -R appuser /app
 USER appuser
 
 EXPOSE 8000
 
-# Runs: alembic upgrade head → uvicorn
 ENTRYPOINT ["./entrypoint.sh"]