diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 112140412..87d93aed6 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -137,9 +137,11 @@ sh-and-py-check:
   allow_failure: false
   script:
     - git config --global --add safe.directory "${PWD}"
-    - .gitlab-ci/run-shellcheck.sh
-    - .gitlab-ci/run-black.sh
-    - .gitlab-ci/run-flake8.sh
+    - tests/shellcheck.sh
+    - tests/black.sh
+    - tests/flake8.sh
+  variables:
+    LINT_WARNINGS_ARE_ERRORS: '1'
   only:
     changes:
       - "**/*.py"
@@ -151,7 +153,9 @@ style-check-mandatory:
   stage: style-check
   allow_failure: false
   script:
-    - .gitlab-ci/run-reuse.sh
+    - tests/reuse.sh
+  variables:
+    LINT_WARNINGS_ARE_ERRORS: '1'
 
 fedora-x86_64:
   extends:
diff --git a/.gitlab-ci/run-black.sh b/.gitlab-ci/run-black.sh
deleted file mode 100755
index fdeaf1684..000000000
--- a/.gitlab-ci/run-black.sh
+++ /dev/null
@@ -1,6 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# shellcheck disable=SC2046
-black --diff --check $(git ls-files '*.py')
diff --git a/.gitlab-ci/run-flake8.sh b/.gitlab-ci/run-flake8.sh
deleted file mode 100755
index 5675a01ef..000000000
--- a/.gitlab-ci/run-flake8.sh
+++ /dev/null
@@ -1,9 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# Disable formatting warnings in flake8, as we use `black` to handle that.
-formatting_warnings=E101,E111,E114,E115,E116,E117,E12,E13,E2,E3,E401,E5,E70,W1,W2,W3,W5
-
-# shellcheck disable=SC2046
-flake8 --max-line-length=88 --ignore="$formatting_warnings" $(git ls-files '*.py')
diff --git a/.gitlab-ci/run-shellcheck.sh b/.gitlab-ci/run-shellcheck.sh
deleted file mode 100755
index abf2e5ef3..000000000
--- a/.gitlab-ci/run-shellcheck.sh
+++ /dev/null
@@ -1,7 +0,0 @@
-#!/bin/bash
-
-set -e
-
-# Ignoring third-party directories that we don't want to parse
-# shellcheck disable=SC2046
-shellcheck $(git ls-files '*.sh' | grep -Ev "glib/libcharset|glib/dirent")
diff --git a/.gitlab-ci/run-tests.sh b/.gitlab-ci/run-tests.sh
index 1189493ba..629385066 100755
--- a/.gitlab-ci/run-tests.sh
+++ b/.gitlab-ci/run-tests.sh
@@ -2,8 +2,6 @@
 
 set -ex
 
-./.gitlab-ci/check-missing-install-tag.py _build
-
 meson test -v \
         -C _build \
         --timeout-multiplier "${MESON_TEST_TIMEOUT_MULTIPLIER}" \
diff --git a/.gitlab-ci/test-msvc.bat b/.gitlab-ci/test-msvc.bat
index 73f972a3c..09ba13c48 100644
--- a/.gitlab-ci/test-msvc.bat
+++ b/.gitlab-ci/test-msvc.bat
@@ -14,7 +14,6 @@ set args=%args:~1%
 :: FIXME: make warnings fatal
 pip3 install --upgrade --user meson==1.2.3 packaging==23.2  || goto :error
 meson setup %args% _build || goto :error
-python .gitlab-ci/check-missing-install-tag.py _build || goto :error
 meson compile -C _build || goto :error
 
 meson test -v -C _build --timeout-multiplier %MESON_TEST_TIMEOUT_MULTIPLIER% || goto :error
diff --git a/meson.build b/meson.build
index c14b7f5f1..85856008c 100644
--- a/meson.build
+++ b/meson.build
@@ -171,6 +171,10 @@ common_test_env = [
   'MALLOC_CHECK_=2',
 ]
 
+if get_option('werror')
+  common_test_env += 'LINT_WARNINGS_ARE_ERRORS=1'
+endif
+
 # Note: this may cause the tests output not to be printed when running in
 # verbose mode, see https://github.com/mesonbuild/meson/issues/11185
 # Can be changed it to 'exitcode' if required during development.
@@ -2545,6 +2549,7 @@ subdir('gmodule')
 subdir('gio')
 subdir('girepository')
 subdir('fuzzing')
+subdir('tests')
 
 # xgettext is optional (on Windows for instance)
 if find_program('xgettext', required : get_option('nls')).found()
diff --git a/tests/black.sh b/tests/black.sh
new file mode 100755
index 000000000..37473bef5
--- /dev/null
+++ b/tests/black.sh
@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+# Copyright 2020 Frederic Martinsons
+# Copyright 2020 Endless OS Foundation, LLC
+# Copyright 2024 Collabora Ltd.
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+set -eu
+
+if [ -z "${G_TEST_SRCDIR-}" ]; then
+    me="$(readlink -f "$0")"
+    G_TEST_SRCDIR="${me%/*}"
+fi
+
+export TEST_NAME=black
+export TEST_REQUIRES_TOOLS="black git"
+
+run_lint () {
+    # shellcheck disable=SC2046
+    black --diff --check $(git ls-files '*.py')
+}
+
+# shellcheck source=tests/lint-common.sh
+. "$G_TEST_SRCDIR/lint-common.sh"
diff --git a/.gitlab-ci/check-missing-install-tag.py b/tests/check-missing-install-tag.py
similarity index 52%
rename from .gitlab-ci/check-missing-install-tag.py
rename to tests/check-missing-install-tag.py
index ab2380421..71e96eb37 100755
--- a/.gitlab-ci/check-missing-install-tag.py
+++ b/tests/check-missing-install-tag.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright © 2022 Collabora, Ltd.
+# Copyright © 2022-2024 Collabora, Ltd.
 #
 # SPDX-License-Identifier: LGPL-2.1-or-later
 #
@@ -18,19 +18,33 @@ from pathlib import Path
 
 def main():
     parser = argparse.ArgumentParser()
-    parser.add_argument("builddir", type=Path)
+    parser.add_argument("builddir", type=Path, nargs="?", default=".")
     args = parser.parse_args()
 
-    success = True
+    print("# TAP version 13")
+
+    count = 0
+    bad = 0
     path = args.builddir / "meson-info" / "intro-install_plan.json"
     with path.open(encoding="utf-8") as f:
         install_plan = json.load(f)
         for target in install_plan.values():
             for info in target.values():
+                count += 1
+
                 if not info["tag"]:
-                    print("Missing install_tag for", info["destination"])
-                    success = False
-    return 0 if success else 1
+                    bad += 1
+                    dest = info["destination"]
+                    print(f"not ok {bad} - Missing install_tag for {dest}")
+
+    if bad == 0:
+        print(f"ok 1 - All {count} installed files have install_tag")
+        print("1..1")
+        return 0
+    else:
+        print(f"# {bad}/{count} installed files do not have install_tag")
+        print(f"1..{bad}")
+        return 1
 
 
 if __name__ == "__main__":
diff --git a/tests/flake8.sh b/tests/flake8.sh
new file mode 100755
index 000000000..10a0a6ffd
--- /dev/null
+++ b/tests/flake8.sh
@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+# Copyright 2020 Frederic Martinsons
+# Copyright 2020 Endless OS Foundation, LLC
+# Copyright 2024 Collabora Ltd.
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+set -eu
+
+if [ -z "${G_TEST_SRCDIR-}" ]; then
+    me="$(readlink -f "$0")"
+    G_TEST_SRCDIR="${me%/*}"
+fi
+
+export TEST_NAME=flake8
+export TEST_REQUIRES_TOOLS="flake8 git"
+
+run_lint () {
+    # Disable formatting warnings in flake8, as we use `black` to handle that.
+    local formatting_warnings=E101,E111,E114,E115,E116,E117,E12,E13,E2,E3,E401,E5,E70,W1,W2,W3,W5
+
+    # shellcheck disable=SC2046
+    flake8 \
+        --max-line-length=88 --ignore="$formatting_warnings" \
+        $(git ls-files '*.py')
+}
+
+# shellcheck source=tests/lint-common.sh
+. "$G_TEST_SRCDIR/lint-common.sh"
diff --git a/tests/lint-common.sh b/tests/lint-common.sh
new file mode 100644
index 000000000..1d1c3d427
--- /dev/null
+++ b/tests/lint-common.sh
@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+# Copyright 2016-2018 Simon McVittie
+# Copyright 2018-2024 Collabora Ltd.
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+set -eu
+
+skip_all () {
+    echo "1..0 # SKIP $*"
+    exit 0
+}
+
+main () {
+    local need_git=
+    local tool
+
+    cd "$G_TEST_SRCDIR/.."
+    echo "TAP version 13"
+
+    # shellcheck disable=SC2046
+    for tool in ${TEST_REQUIRES_TOOLS-}; do
+        command -v "$tool" >/dev/null || skip_all "$tool not found"
+        if [ "$tool" = git ]; then
+            need_git=1
+        fi
+    done
+
+    if [ -n "${need_git-}" ] && ! test -e .git; then
+        skip_all "not a git checkout"
+    fi
+
+    echo "1..1"
+
+    if run_lint >&2; then
+        echo "ok 1"
+        exit 0
+    elif [ -n "${LINT_WARNINGS_ARE_ERRORS-}" ]; then
+        echo "not ok 1 - warnings from ${TEST_NAME-"lint tool"}"
+        exit 1
+    else
+        echo "not ok 1 # TO""DO warnings from ${TEST_NAME-"lint tool"}"
+        exit 0
+    fi
+}
+
+main
diff --git a/tests/meson.build b/tests/meson.build
new file mode 100644
index 000000000..ca739c458
--- /dev/null
+++ b/tests/meson.build
@@ -0,0 +1,27 @@
+# Copyright 2024 Collabora Ltd.
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+lint_scripts = [
+  'black.sh',
+  'flake8.sh',
+  'reuse.sh',
+  'shellcheck.sh',
+]
+
+foreach test_name : lint_scripts
+  test(
+    test_name, files(test_name),
+    env : common_test_env,
+    suite : 'lint',
+    protocol : 'tap',
+  )
+endforeach
+
+test(
+  'check-missing-install-tag.py',
+  python,
+  args : ['-B', files('check-missing-install-tag.py')],
+  env : common_test_env,
+  suite : 'lint',
+  protocol : 'tap',
+)
\ No newline at end of file
diff --git a/.gitlab-ci/run-reuse.sh b/tests/reuse.sh
similarity index 69%
rename from .gitlab-ci/run-reuse.sh
rename to tests/reuse.sh
index a45b4dd3f..e9d9e0641 100755
--- a/.gitlab-ci/run-reuse.sh
+++ b/tests/reuse.sh
@@ -1,23 +1,43 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # Copyright 2022 Endless OS Foundation, LLC
+# Copyright 2024 Collabora Ltd.
 #
 # SPDX-License-Identifier: LGPL-2.1-or-later
 #
 # Original author: Philip Withnall
 
-set -e
+set -eu
+
+if [ -z "${G_TEST_SRCDIR-}" ]; then
+    me="$(readlink -f "$0")"
+    G_TEST_SRCDIR="${me%/*}"
+fi
+
+skip_all () {
+    echo "1..0 # SKIP $*"
+    exit 0
+}
+
+cd "$G_TEST_SRCDIR/.."
+echo "TAP version 13"
+
+command -v git >/dev/null || skip_all "git not found"
+command -v reuse >/dev/null || skip_all "reuse not found"
+test -e .git || skip_all "not a git checkout"
+
+echo "1..1"
 
 # We need to make sure the submodules are up to date, or `reuse lint` will fail
 # when it tries to run `git status` internally
-git submodule update --init
+git submodule update --init >&2
 
 # Run `reuse lint` on the code base and see if the number of files without
 # suitable copyright/licensing information has increased from a baseline
 # FIXME: Eventually this script can check whether *any* files are missing
 # information. But for now, let’s slowly improve the baseline.
-files_without_copyright_information_max=346
-files_without_license_information_max=417
+files_without_copyright_information_max=343
+files_without_license_information_max=414
 
 # The || true is because `reuse lint` will exit with status 1 if the project is not compliant
 # FIXME: Once https://github.com/fsfe/reuse-tool/issues/512 or
@@ -36,27 +56,36 @@ files_without_license_information="$(( total_files - files_with_license_informat
 
 if [ "${files_without_copyright_information}" -gt "${files_without_copyright_information_max}" ] || \
    [ "${files_without_license_information}" -gt "${files_without_license_information_max}" ]; then
-  echo "${lint_output}"
+  echo "${lint_output}" >&2
 fi
 
 if [ "${files_without_copyright_information}" -gt "${files_without_copyright_information_max}" ]; then
-  echo ""
-  echo "Error: New files added without REUSE-compliant copyright information"
-  echo "Please make sure that all files added in this branch/merge request have correct copyright information"
+  echo "" >&2
+  echo "Error: New files added without REUSE-compliant copyright information" >&2
+  echo "Please make sure that all files added in this branch/merge request have correct copyright information" >&2
   error=1
 fi
 
 if [ "${files_without_license_information}" -gt "${files_without_license_information_max}" ]; then
-  echo ""
-  echo "Error: New files added without REUSE-compliant licensing information"
-  echo "Please make sure that all files added in this branch/merge request have correct license information"
+  echo "" >&2
+  echo "Error: New files added without REUSE-compliant licensing information" >&2
+  echo "Please make sure that all files added in this branch/merge request have correct license information" >&2
   error=1
 fi
 
 if [ "${error}" -eq "1" ]; then
-  echo ""
-  echo "See https://reuse.software/tutorial/#step-2 for information on how to add REUSE information"
-  echo "Also see https://gitlab.gnome.org/GNOME/glib/-/issues/1415"
+  echo "" >&2
+  echo "See https://reuse.software/tutorial/#step-2 for information on how to add REUSE information" >&2
+  echo "Also see https://gitlab.gnome.org/GNOME/glib/-/issues/1415" >&2
 fi
 
-exit "${error}"
\ No newline at end of file
+if [ "${error}" -eq 0 ]; then
+    echo "ok 1"
+    exit 0
+elif [ -n "${LINT_WARNINGS_ARE_ERRORS-}" ]; then
+    echo "not ok 1 - warnings from reuse"
+    exit "${error}"
+else
+    echo "not ok 1 # TO""DO warnings from reuse"
+    exit 0
+fi
diff --git a/tests/shellcheck.sh b/tests/shellcheck.sh
new file mode 100755
index 000000000..4f5ce6209
--- /dev/null
+++ b/tests/shellcheck.sh
@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+# Copyright 2020 Frederic Martinsons
+# Copyright 2024 Collabora Ltd.
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+set -eu
+
+if [ -z "${G_TEST_SRCDIR-}" ]; then
+    me="$(readlink -f "$0")"
+    G_TEST_SRCDIR="${me%/*}"
+fi
+
+export TEST_NAME=shellcheck
+export TEST_REQUIRES_TOOLS="git shellcheck"
+
+run_lint () {
+    # Ignoring third-party directories that we don't want to parse
+    # shellcheck disable=SC2046
+    shellcheck $(git ls-files '*.sh' | grep -Ev "glib/libcharset|glib/dirent")
+}
+
+# shellcheck source=tests/lint-common.sh
+. "$G_TEST_SRCDIR/lint-common.sh"