anchor.diff:      python3 \
       && rm -rf /var/lib/apt/lists/*
   
  -RUN ["/bin/bash", "-c", ". scripts/env.sh && make MAKE_OPTS=-j4 lowrisc-llvm-debug"]
  +RUN /bin/bash -c \
  +    ". scripts/env.sh && make MAKE_OPTS=-j4 lowrisc-llvm-debug && rm -rf build"
   
   # SBT
  -RUN ["/bin/bash", "-c", ". scripts/env.sh && make sbt-debug"]
  +RUN /bin/bash -c \
  +    ". scripts/env.sh && make sbt-debug && rm -rf build"
   
  -# riscv emulators
  -RUN git submodule update --recursive --init submodules/riscv-fesvr
  -RUN git submodule update --recursive --init submodules/riscv-isa-sim
  -RUN git submodule update --recursive --init submodules/riscv-pk
  -
  -RUN ["/bin/bash", "-c", ". scripts/env.sh && make riscv-isa-sim"]
  -RUN ["/bin/bash", "-c", ". scripts/env.sh && make riscv-pk-32"]
  +# spike
  +RUN /bin/bash -c \
  +    ". scripts/env.sh && make riscv-isa-sim && rm -rf build"
  +RUN /bin/bash -c \
  +    ". scripts/env.sh && make riscv-pk-32 && rm -rf build"
   
   # qemu
  -RUN git submodule update --recursive --init submodules/riscv-qemu
  -
   RUN apt-get update \
       && apt-get install -y \
       python \
  
positive.code:     libglib2.0-dev \
      && rm -rf /var/lib/apt/lists/*
  
  RUN ["/bin/bash", "-c", ". scripts/env.sh && make qemu-user"]
  
  # needed by test-system
  #RUN apt-get update \
  
negative.code:     && rm -rf /var/lib/apt/lists/*
  
  # riscv-gnu-toolchain
  RUN /bin/bash -c \
      ". scripts/env.sh && make riscv-gnu-toolchain && rm -rf build"
  RUN /bin/bash -c \
      ". scripts/env.sh && make riscv-gnu-toolchain-linux && rm -rf build"
  
  # LLVM/clang
  RUN apt-get update \
      && apt-get install -y \
      cmake \
  