diff --git a/tools/docker/Dockerfile.test_precommit b/tools/docker/Dockerfile.test_precommit
new file mode 100644
index 0000000000..5528c4314a
--- /dev/null
+++ b/tools/docker/Dockerfile.test_precommit
@@ -0,0 +1,23 @@
+#
+# This file was created by generate_dockerfiles.py.
+# Usage: docker build -f ./Dockerfile.test_precommit ../../
+#
+
+FROM ubuntu:20.04
+
+# Install dependencies.
+WORKDIR /opt/cp2k-precommit
+COPY ./tools/precommit/ /opt/cp2k-precommit/
+RUN ./install_requirements.sh
+
+# Install sources.
+WORKDIR /opt/cp2k
+COPY ./ ./
+
+# Run precommit test.
+RUN ./tools/docker/scripts/test_precommit.sh 2>&1 | tee report.log
+
+# Output the report if the image is old and was therefore pulled from the build cache.
+CMD cat $(find ./report.log -mmin +10) | sed '/^Summary:/ s/$/ (cached)/'
+
+#EOF
diff --git a/tools/docker/generate_dockerfiles.py b/tools/docker/generate_dockerfiles.py
index 8a33d1d635..1649c7c5e0 100755
--- a/tools/docker/generate_dockerfiles.py
+++ b/tools/docker/generate_dockerfiles.py
@@ -66,6 +66,9 @@ def main() -> None:
     with OutputFile(f"Dockerfile.test_manual", args.check) as f:
         f.write(toolchain_full() + manual())
 
+    with OutputFile(f"Dockerfile.test_precommit", args.check) as f:
+        f.write(precommit())
+
     for name in "aiida", "ase", "gromacs", "i-pi":
         with OutputFile(f"Dockerfile.test_{name}", args.check) as f:
             f.write(toolchain_full() + test_3rd_party(name))
@@ -153,6 +156,28 @@ RUN ./test_manual.sh 2>&1 | tee report.log
     )
 
 
+# ======================================================================================
+def precommit() -> str:
+    return (
+        fr"""
+FROM ubuntu:20.04
+
+# Install dependencies.
+WORKDIR /opt/cp2k-precommit
+COPY ./tools/precommit/ /opt/cp2k-precommit/
+RUN ./install_requirements.sh
+
+# Install sources.
+WORKDIR /opt/cp2k
+COPY ./ ./
+
+# Run precommit test.
+RUN ./tools/docker/scripts/test_precommit.sh 2>&1 | tee report.log
+"""
+        + print_cached_report()
+    )
+
+
 # ======================================================================================
 def test_3rd_party(name: str) -> str:
     return (
diff --git a/tools/docker/scripts/test_precommit.sh b/tools/docker/scripts/test_precommit.sh
new file mode 100755
index 0000000000..56215f392c
--- /dev/null
+++ b/tools/docker/scripts/test_precommit.sh
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# author: Ole Schuett
+
+echo -e "\n========== Starting Precommit Server =========="
+cd ./tools/precommit/ || exit 1
+export REVISION="unknown revision"
+gunicorn --bind=:8080 --workers=1 --threads=8 --timeout=0 precommit_server:app &> /var/tmp/precommit_server.logs &
+sleep 3
+cat /var/tmp/precommit_server.logs
+
+echo -e "\n========== Running Precommit Checks =========="
+export CP2K_PRECOMMIT_SERVER="http://127.0.0.1:8080"
+./precommit.py --no-cache --progressbar-wait=10
+echo -e "\n"
+
+exit 0 # Prevent CI from overwriting precommit.py's summary message.
+
+#EOF
diff --git a/tools/precommit/Dockerfile b/tools/precommit/Dockerfile
index 48daaea1f7..1f0d1590ea 100644
--- a/tools/precommit/Dockerfile
+++ b/tools/precommit/Dockerfile
@@ -2,55 +2,13 @@ FROM ubuntu:20.04
 
 # author: Ole Schuett
 
-# Install clang-format, shellcheck, and other Ubuntu packages.
-# https://github.com/koalaman/shellcheck
-# https://clang.llvm.org/docs/ClangFormat.html
-RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
-    apt-get update -qq && apt-get install -qq --no-install-recommends \
-    ca-certificates \
-    clang-format \
-    git \
-    less \
-    nano \
-    npm \
-    python3 \
-    python3-pip \
-    python3-wheel \
-    python3-setuptools \
-    shellcheck \
-    wget \
-  && rm -rf /var/lib/apt/lists/*
-
-# Install markdownlint-cli and dependencies.
-# https://github.com/DavidAnson/markdownlint
-# https://github.com/igorshubovych/markdownlint-cli 
 WORKDIR /opt/cp2k-precommit
-COPY package.json package-lock.json ./
-RUN npm install .
-RUN ln -s /opt/cp2k-precommit/node_modules/markdownlint-cli/markdownlint.js /usr/bin/markdownlint
-
-# Install black, flask, gunicorn, and dependencies.
-# https://github.com/psf/black
-COPY requirements.txt .
-RUN pip3 install --quiet -r requirements.txt
-
-# Install shfmt.
-# https://github.com/mvdan/sh
-RUN wget -q https://github.com/mvdan/sh/releases/download/v3.2.2/shfmt_v3.2.2_linux_amd64 && \
-    echo '3a32a69286a19491a81fcd854154f0d886c379ff28d99e32d5594490b8bbef4b shfmt_v3.2.2_linux_amd64' | sha256sum --check && \
-    chmod +x shfmt_v3.2.2_linux_amd64 && \
-    ln -s /opt/cp2k-precommit/shfmt_v3.2.2_linux_amd64 /usr/bin/shfmt
-
-# Clone cp2k repository (needed for CI mode).
-RUN git clone --quiet --recursive --single-branch -b master https://github.com/cp2k/cp2k.git /workspace/cp2k
-
-# Install Flask app.
-COPY precommit_server.py .
+COPY . /opt/cp2k-precommit/
+RUN ./install_requirements.sh
 
 ARG REVISION
 ENV REVISION=${REVISION}
 
-COPY entrypoint.sh .
-CMD ["./entrypoint.sh"]
+CMD ["gunicorn", "--bind=:8080", "--workers=1", "--threads=8", "--timeout=0", "precommit_server:app"]
 
 #EOF
diff --git a/tools/precommit/entrypoint.sh b/tools/precommit/entrypoint.sh
deleted file mode 100755
index 59aa904fbb..0000000000
--- a/tools/precommit/entrypoint.sh
+++ /dev/null
@@ -1,31 +0,0 @@
-#!/bin/bash -e
-
-# author: Ole Schuett
-
-trap "exit" INT
-
-if [ -z "${GIT_REF}" ]; then
-  # Server mode.
-  gunicorn --bind=:8080 --workers=1 --threads=8 --timeout=0 precommit_server:app &
-  wait # Can be interrupted with ctrl-C.
-else
-  # CI mode.
-  echo -e "\n========== Fetching Git Commit =========="
-  cd /workspace/cp2k
-  git fetch --quiet origin "${GIT_BRANCH}"
-  git reset --quiet --hard "${GIT_REF}"
-  git submodule update --init --recursive
-  git --no-pager log -1 --pretty='%nCommitSHA: %H%nCommitTime: %ci%nCommitAuthor: %an%nCommitSubject: %s%n'
-
-  echo -e "\n========== Starting Precommit Server =========="
-  cd ./tools/precommit/
-  gunicorn --bind=:8080 --workers=1 --threads=8 --timeout=0 precommit_server:app &> /workspace/precommit_server.logs &
-  sleep 3
-  cat /workspace/precommit_server.logs
-
-  echo -e "\n========== Running Precommit Checks =========="
-  export CP2K_PRECOMMIT_SERVER="http://127.0.0.1:8080"
-  ./precommit.py --no-cache --progressbar-wait=10 || true
-fi
-
-#EOF
diff --git a/tools/precommit/install_requirements.sh b/tools/precommit/install_requirements.sh
new file mode 100755
index 0000000000..7cd49da4f4
--- /dev/null
+++ b/tools/precommit/install_requirements.sh
@@ -0,0 +1,42 @@
+#!/bin/bash -e
+
+# author: Ole Schuett
+
+# Install clang-format, shellcheck, and other Ubuntu packages.
+# https://github.com/koalaman/shellcheck
+# https://clang.llvm.org/docs/ClangFormat.html
+export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true
+apt-get update -qq
+apt-get install -qq --no-install-recommends \
+  ca-certificates \
+  clang-format \
+  git \
+  less \
+  nano \
+  npm \
+  python3 \
+  python3-pip \
+  python3-wheel \
+  python3-setuptools \
+  shellcheck \
+  wget
+rm -rf /var/lib/apt/lists/*
+
+# Install markdownlint-cli and dependencies.
+# https://github.com/DavidAnson/markdownlint
+# https://github.com/igorshubovych/markdownlint-cli
+npm install .
+ln -s /opt/cp2k-precommit/node_modules/markdownlint-cli/markdownlint.js /usr/bin/markdownlint
+
+# Install black, flask, gunicorn, and dependencies.
+# https://github.com/psf/black
+pip3 install --quiet -r requirements.txt
+
+# Install shfmt.
+# https://github.com/mvdan/sh
+wget -q https://github.com/mvdan/sh/releases/download/v3.2.2/shfmt_v3.2.2_linux_amd64
+echo '3a32a69286a19491a81fcd854154f0d886c379ff28d99e32d5594490b8bbef4b shfmt_v3.2.2_linux_amd64' | sha256sum --check
+chmod +x shfmt_v3.2.2_linux_amd64
+ln -s /opt/cp2k-precommit/shfmt_v3.2.2_linux_amd64 /usr/bin/shfmt
+
+#EOF