| 1234567891011121314151617181920212223 | FROM rust:1.56.1 as builderWORKDIR /appCOPY . .WORKDIR /app/backendENV SQLX_OFFLINE trueRUN RUSTFLAGS="-C opt-level=2" cargo build --release --bin backend# Size optimization#RUN strip ./target/release/backendFROM debian:bullseye-slim AS runtimeWORKDIR /appRUN apt-get update -y \    && apt-get install -y --no-install-recommends openssl \    # Clean up    && apt-get autoremove -y \    && apt-get clean -y \    && rm -rf /var/lib/apt/lists/*COPY --from=builder /app/backend/target/release/backend /usr/local/bin/backendCOPY --from=builder /app/backend/configuration configurationENV APP_ENVIRONMENT productionCMD ["backend"]
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