diff --git a/tests/ci/docker/debian.mpi b/tests/ci/docker/debian.mpi
index 9b4e946..fb5a80d 100644
--- a/tests/ci/docker/debian.mpi
+++ b/tests/ci/docker/debian.mpi
@@ -1,45 +1,45 @@
 FROM debian:stable-slim
 
 MAINTAINER Lucas Frérot
 
 # Add contrib and non-free
 RUN sed -i 's/main/main contrib non-free/' /etc/apt/sources.list
 
 # Core dependencies
 RUN apt-get -qq update && apt-get install -qq -y --no-install-recommends \
     g++ \
     git \
     libboost-dev \
     libthrust-dev \
     libopenmpi-dev \
     libfftw3-dev \
     libfftw3-mpi-dev \
     scons \
   && rm -rf /var/lib/apt/lists/*
 
 # Python dependencies
 RUN apt-get -qq update && apt-get install -qq -y --no-install-recommends \
     python3-dev \
     python3-pip \
     python3-numpy \
     python3-scipy \
     python3-h5py \
     python3-netcdf4 \
     python3-mpi4py \
   && rm -rf /var/lib/apt/lists/*
 RUN python3 -m pip install pytest uvw
 
 # Documentation dependencies
 RUN apt-get -qq update && apt-get install -qq -y --no-install-recommends \
     python3-sphinx \
     python3-breathe \
     python3-sphinx-rtd-theme \
     doxygen \
   && rm -rf /var/lib/apt/lists/*
 
 # Linting etc.
 RUN apt-get -qq update && apt-get install -qq -y --no-install-recommends \
     ccache \
     clang-format \
-    python3-flake8 \
   && rm -rf /var/lib/apt/lists/*
+RUN python3 -m pip install flake8