diff --git a/.copier-answers.yml b/.copier-answers.yml
index b2d9f271..2411a117 100644
--- a/.copier-answers.yml
+++ b/.copier-answers.yml
@@ -1,5 +1,5 @@
 # Changes here will be overwritten by Copier; NEVER EDIT MANUALLY
-_commit: 8484c9e
+_commit: 7afbc9a
 _src_path: gh:scipp/copier_template
 description: Diffraction data reduction for the European Spallation Source
 max_python: '3.12'
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 4b1d1114..44266a23 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -21,7 +21,7 @@ jobs:
         run: |
           echo "min_python=$(cat .github/workflows/python-version-ci)" >> $GITHUB_OUTPUT
           echo "min_tox_env=py$(cat .github/workflows/python-version-ci | sed 's/\.//g')" >> $GITHUB_OUTPUT
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
         with:
           python-version-file: '.github/workflows/python-version-ci'
       - uses: pre-commit/action@v3.0.1
diff --git a/.github/workflows/copier.yml b/.github/workflows/copier.yml
new file mode 100644
index 00000000..b1fe6ce4
--- /dev/null
+++ b/.github/workflows/copier.yml
@@ -0,0 +1,25 @@
+name: Copier template sync
+
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '0 1 * * 1'
+
+jobs:
+  update:
+    name: Sync with copier template
+    runs-on: 'ubuntu-latest'
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.X'
+      - run: pip install copier
+      - run: copier update --skip-answered --vcs-ref=HEAD --conflict=rej
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v6
+        with:
+          title: '[CRON] Sync with copier template'
+          body: |
+            This PR updates the project to the latest version of scipp's [copier-template](https://github.com/scipp/copier_template).
+            Remember to check for any conflicts and resolve them.
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index d24932b1..7e5a7bc6 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -47,8 +47,9 @@ jobs:
       - uses: actions/checkout@v4
         with:
           ref: ${{ inputs.branch == '' && github.ref_name || inputs.branch }}
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
           fetch-depth: 0  # history required so cmake can determine version
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
         with:
           python-version-file: '.github/workflows/python-version-ci'
       - run: python -m pip install --upgrade pip
@@ -59,12 +60,12 @@ jobs:
         if: ${{ inputs.version == '' }}
       - run: tox -e linkcheck
         if: ${{ inputs.linkcheck }}
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: docs_html
           path: html/
 
-      - uses: JamesIves/github-pages-deploy-action@v4.5.0
+      - uses: JamesIves/github-pages-deploy-action@v4.6.0
         if: ${{ inputs.publish }}
         with:
           branch: gh-pages
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 2eec2f00..d1317a76 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -28,7 +28,7 @@ jobs:
             boa
       - run: conda mambabuild --channel conda-forge --channel scipp --no-anaconda-upload --override-channels --output-folder conda/package conda
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: conda-package-noarch
           path: conda/package/noarch/*.tar.bz2
@@ -42,7 +42,7 @@ jobs:
         with:
           fetch-depth: 0  # history required so setuptools_scm can determine version
 
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
         with:
           python-version-file: '.github/workflows/python-version-ci'
 
@@ -53,7 +53,7 @@ jobs:
         run: python -m build
 
       - name: Upload wheels
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: dist
           path: dist
@@ -67,7 +67,7 @@ jobs:
       id-token: write
     if: github.event_name == 'release' && github.event.action == 'published'
     steps:
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
       - uses: pypa/gh-action-pypi-publish@v1.8.14
 
   upload_conda:
@@ -77,7 +77,7 @@ jobs:
     if: github.event_name == 'release' && github.event.action == 'published'
 
     steps:
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
       - uses: mamba-org/setup-micromamba@v1
         with:
           environment-name: upload-env
@@ -101,7 +101,7 @@ jobs:
     permissions:
       contents: write  # This is needed so that the action can upload the asset
     steps:
-    - uses: actions/download-artifact@v3
+    - uses: actions/download-artifact@v4
     - name: Zip documentation
       run: |
         mv docs_html documentation-${{ github.ref_name }}
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 3638e922..5f56a069 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -54,7 +54,7 @@ jobs:
       - run: python -m pip install --upgrade pip
       - run: python -m pip install -r ${{ inputs.pip-recipe }}
       - run: tox -e ${{ inputs.tox-env }}
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         if: ${{ inputs.coverage-report }}
         with:
           name: CoverageReport
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 19830db7..508073fe 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -13,15 +13,6 @@ repos:
       - id: trailing-whitespace
         args: [ --markdown-linebreak-ext=md ]
         exclude: '\.svg'
-  - repo: https://github.com/pycqa/isort
-    rev: 5.12.0
-    hooks:
-      - id: isort
-        name: isort (python)
-  - repo: https://github.com/psf/black-pre-commit-mirror
-    rev: 23.11.0
-    hooks:
-      - id: black
   - repo: https://github.com/kynan/nbstripout
     rev: 0.6.0
     hooks:
@@ -29,18 +20,14 @@ repos:
         types: [ "jupyter" ]
         args: [ "--drop-empty-cells",
                 "--extra-keys 'metadata.language_info.version cell.metadata.jp-MarkdownHeadingCollapsed cell.metadata.pycharm'" ]
-  - repo: https://github.com/pycqa/flake8
-    rev: 6.1.0
-    hooks:
-      - id: flake8
-        types: ["python"]
-        additional_dependencies: ["flake8-bugbear==23.9.16"]
-  - repo: https://github.com/pycqa/bandit
-    rev: 1.7.5
-    hooks:
-      - id: bandit
-        additional_dependencies: ["bandit[toml]"]
-        args: ["-c", "pyproject.toml"]
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.4.1
+    hooks:
+      - id: ruff
+        args: [ --fix ]
+        types_or: [ python, pyi, jupyter ]
+      - id: ruff-format
+        types_or: [ python, pyi ]
   - repo: https://github.com/codespell-project/codespell
     rev: v2.2.6
     hooks:
diff --git a/conda/meta.yaml b/conda/meta.yaml
index 8065e193..593981f5 100644
--- a/conda/meta.yaml
+++ b/conda/meta.yaml
@@ -6,6 +6,11 @@ package:
 source:
   path: ..
 
+
+{% set pyproject = load_file_data('pyproject.toml') %}
+{% set dependencies = pyproject.get('project', {}).get('dependencies', {}) %}
+
+
 requirements:
   build:
     - setuptools
@@ -23,6 +28,11 @@ requirements:
     - scippnexus>=23.12.0
     - python>=3.10
 
+  {% for package in dependencies %}
+    - {% if package == "graphviz" %}python-graphviz{% else %}{{ package }}{% endif %}
+  {% endfor %}
+
+
 test:
   imports:
     - ess.diffraction
diff --git a/docs/conf.py b/docs/conf.py
index 5ae0e872..17b45932 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -3,15 +3,14 @@
 import doctest
 import os
 import sys
-
-from ess import diffraction
+from importlib.metadata import version as get_version
 
 sys.path.insert(0, os.path.abspath('.'))
 
 # General information about the project.
-project = u'ESSdiffraction'
-copyright = u'2024 Scipp contributors'
-author = u'Scipp contributors'
+project = 'ESSdiffraction'
+copyright = '2024 Scipp contributors'
+author = 'Scipp contributors'
 
 html_show_sourcelink = True
 
@@ -112,10 +111,8 @@
 # built documents.
 #
 
-# The short X.Y version.
-version = diffraction.__version__
-# The full version, including alpha/beta/rc tags.
-release = diffraction.__version__
+release = get_version("essdiffraction")
+version = ".".join(release.split('.')[:3])  # CalVer
 
 warning_is_error = True
 
diff --git a/docs/developer/coding-conventions.md b/docs/developer/coding-conventions.md
index b23c0eb4..4fafc18d 100644
--- a/docs/developer/coding-conventions.md
+++ b/docs/developer/coding-conventions.md
@@ -2,7 +2,7 @@
 
 ## Code formatting
 
-There are no explicit code formatting conventions since we use `black` to enforce a format.
+There are no explicit code formatting conventions since we use `ruff` to enforce a format.
 
 ## Docstring format
 
diff --git a/docs/user-guide/dream/dream-data-reduction.ipynb b/docs/user-guide/dream/dream-data-reduction.ipynb
index 91095402..06cd8586 100644
--- a/docs/user-guide/dream/dream-data-reduction.ipynb
+++ b/docs/user-guide/dream/dream-data-reduction.ipynb
@@ -15,8 +15,6 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from pathlib import Path\n",
-    "\n",
     "import scipp as sc\n",
     "import scippneutron as scn\n",
     "import sciline\n",
diff --git a/docs/user-guide/sns-instruments/POWGEN_data_reduction.ipynb b/docs/user-guide/sns-instruments/POWGEN_data_reduction.ipynb
index dbdd7dbd..f7853190 100644
--- a/docs/user-guide/sns-instruments/POWGEN_data_reduction.ipynb
+++ b/docs/user-guide/sns-instruments/POWGEN_data_reduction.ipynb
@@ -26,7 +26,6 @@
     "import scippneutron as scn\n",
     "import sciline\n",
     "\n",
-    "import ess.diffraction\n",
     "from ess import powder\n",
     "from ess.powder.external import powgen\n",
     "from ess.powder.types import *"
diff --git a/pyproject.toml b/pyproject.toml
index ab54e69f..6d99d653 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -67,17 +67,43 @@ filterwarnings = [
   'ignore:\s*Pyarrow will become a required dependency of pandas:DeprecationWarning',
 ]
 
-[tool.bandit]
-# Excluding tests because bandit doesn't like `assert`.
-exclude_dirs = ["docs/conf.py", "tests"]
+[tool.ruff]
+line-length = 88
+extend-include = ["*.ipynb"]
+extend-exclude = [
+    ".*", "__pycache__", "build", "dist", "install",
+]
+
+[tool.ruff.lint]
+# See https://docs.astral.sh/ruff/rules/
+select = ["B", "C4", "DTZ", "E", "F", "G", "I", "PERF", "PGH", "PT", "PYI", "RUF", "S", "T20", "W"]
+ignore = [
+    # Conflict with ruff format, see
+    # https://docs.astral.sh/ruff/formatter/#conflicting-lint-rules
+    "COM812", "COM819", "D206", "D300", "E111", "E114", "E117", "ISC001", "ISC002", "Q000", "Q001", "Q002", "Q003", "W191",
+]
+fixable = ["I001", "B010"]
+isort.known-first-party = ["essdiffraction"]
+pydocstyle.convention = "numpy"
 
-[tool.black]
-skip-string-normalization = true
+[tool.ruff.lint.per-file-ignores]
+# those files have an increased risk of relying on import order
+"__init__.py" = ["I"]
+"tests/*" = [
+    "S101",  # asserts are fine in tests
+    "B018",  # 'useless expressions' are ok because some tests just check for exceptions
+]
+"*.ipynb" = [
+    "E501",  # longer lines are sometimes more readable
+    "F403",  # *-imports used with domain types
+    "F405",  # linter may fail to find names because of *-imports
+    "I",  # we don't collect imports at the top
+    "S101",  # asserts are used for demonstration and are safe in notebooks
+    "T201",  # printing is ok for demonstration purposes
+]
 
-[tool.isort]
-skip_gitignore = true
-profile = "black"
-known_first_party = ["essdiffraction"]
+[tool.ruff.format]
+quote-style = "preserve"
 
 [tool.mypy]
 strict = true
@@ -87,5 +113,4 @@ enable_error_code = [
     "redundant-expr",
     "truthy-bool",
 ]
-show_error_codes = true
 warn_unreachable = true
diff --git a/setup.cfg b/setup.cfg
deleted file mode 100644
index 1ba190c5..00000000
--- a/setup.cfg
+++ /dev/null
@@ -1,4 +0,0 @@
-[flake8]
-# See https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#line-length
-max-line-length = 88
-extend-ignore = E203
diff --git a/src/ess/diffraction/__init__.py b/src/ess/diffraction/__init__.py
index f101246f..c42366fc 100644
--- a/src/ess/diffraction/__init__.py
+++ b/src/ess/diffraction/__init__.py
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright (c) 2024 Scipp contributors (https://github.com/scipp)
+# ruff: noqa: E402, F401
 
 """
 Components for diffraction experiments (powder and single crystal).
diff --git a/src/ess/dream/__init__.py b/src/ess/dream/__init__.py
index 55445452..bb50dc01 100644
--- a/src/ess/dream/__init__.py
+++ b/src/ess/dream/__init__.py
@@ -4,6 +4,7 @@
 """
 Components for DREAM
 """
+
 import importlib.metadata
 
 from . import beamline, data
diff --git a/src/ess/dream/instrument_view.py b/src/ess/dream/instrument_view.py
index 06294535..fedb9bde 100644
--- a/src/ess/dream/instrument_view.py
+++ b/src/ess/dream/instrument_view.py
@@ -116,9 +116,9 @@ def _add_module_control(self):
 
         self.fig = self.scatter[0]
         self.cutting_tool = self.scatter[1]
-        self.artist_mapping = {
-            name: key for name, key in zip(self.data.keys(), self.fig.artists.keys())
-        }
+        self.artist_mapping = dict(
+            zip(self.data.keys(), self.fig.artists.keys(), strict=True)
+        )
         self.checkboxes = {
             key: ipw.Checkbox(
                 value=True,
@@ -130,8 +130,10 @@ def _add_module_control(self):
         }
 
         self.modules_widget = ipw.HBox(
-            [ipw.HTML(value="Modules:     ")]
-            + list(self.checkboxes.values())
+            [
+                ipw.HTML(value="Modules:     "),
+                *self.checkboxes.values(),
+            ]
         )
         for key, ch in self.checkboxes.items():
             ch.key = key
diff --git a/src/ess/dream/io/geant4.py b/src/ess/dream/io/geant4.py
index 63a5dbcd..6a671697 100644
--- a/src/ess/dream/io/geant4.py
+++ b/src/ess/dream/io/geant4.py
@@ -8,8 +8,6 @@
 import numpy as np
 import sciline
 import scipp as sc
-from ess.reduce.nexus import extract_detector_data
-
 from ess.powder.types import (
     DetectorName,
     FilePath,
@@ -17,6 +15,7 @@
     RawDetectorData,
     RunType,
 )
+from ess.reduce.nexus import extract_detector_data
 
 MANTLE_DETECTOR_ID = sc.index(7)
 HIGH_RES_DETECTOR_ID = sc.index(8)
@@ -28,7 +27,7 @@ class AllRawDetectors(sciline.Scope[RunType, sc.DataGroup], sc.DataGroup):
 
 
 def load_geant4_csv(
-    file_path: Union[FilePath[RunType], str, StringIO, BytesIO]
+    file_path: Union[FilePath[RunType], str, StringIO, BytesIO],
 ) -> AllRawDetectors[RunType]:
     """Load a GEANT4 CSV file for DREAM.
 
@@ -73,7 +72,7 @@ def extract_geant4_detector_data(
 
 
 def _load_raw_events(
-    file_path: Union[str, os.PathLike, StringIO, BytesIO]
+    file_path: Union[str, os.PathLike, StringIO, BytesIO],
 ) -> sc.DataArray:
     table = sc.io.load_csv(
         file_path, sep='\t', header_parser='bracket', data_columns=[]
diff --git a/src/ess/powder/__init__.py b/src/ess/powder/__init__.py
index e0f404c2..e2c69c75 100644
--- a/src/ess/powder/__init__.py
+++ b/src/ess/powder/__init__.py
@@ -4,6 +4,7 @@
 """
 Components for powder diffraction experiments.
 """
+
 import importlib.metadata
 
 from . import conversion, correction, filtering, grouping, smoothing, uncertainty
diff --git a/src/ess/powder/correction.py b/src/ess/powder/correction.py
index 2fae36c8..d950f993 100644
--- a/src/ess/powder/correction.py
+++ b/src/ess/powder/correction.py
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
 """Correction algorithms for powder diffraction."""
+
 from typing import Any, Dict, Optional
 
 import scipp as sc
diff --git a/src/ess/powder/external/__init__.py b/src/ess/powder/external/__init__.py
index 339a5635..71c147b0 100644
--- a/src/ess/powder/external/__init__.py
+++ b/src/ess/powder/external/__init__.py
@@ -7,6 +7,7 @@
 It only serves as helpers to develop workflows until it is determined,
 which mechanisms and interfaces will be used at ESS.
 """
+
 from pathlib import Path
 from typing import Dict, Optional, Union
 
diff --git a/src/ess/powder/filtering.py b/src/ess/powder/filtering.py
index 272d97be..45f9e247 100644
--- a/src/ess/powder/filtering.py
+++ b/src/ess/powder/filtering.py
@@ -6,6 +6,7 @@
 
 IMPORTANT Will be moved to a different place and potentially modified.
 """
+
 from contextlib import contextmanager
 from numbers import Real
 
diff --git a/tests/dream/instrument_view_test.py b/tests/dream/instrument_view_test.py
index d67bde6c..9cd9aa01 100644
--- a/tests/dream/instrument_view_test.py
+++ b/tests/dream/instrument_view_test.py
@@ -4,11 +4,10 @@
 import numpy as np
 import pytest
 import scipp as sc
-
 from ess.dream.instrument_view import InstrumentView
 
 
-@pytest.fixture
+@pytest.fixture()
 def fake_instrument_data(modules=('bank1', 'bank2', 'bank3', 'bank4', 'bank5')):
     rng = np.random.default_rng()
 
@@ -16,7 +15,7 @@ def fake_instrument_data(modules=('bank1', 'bank2', 'bank3', 'bank4', 'bank5')):
     npix = 300
     ntof = 100
     locations = range(len(modules))
-    for name, loc in zip(modules, locations):
+    for name, loc in zip(modules, locations, strict=True):
         position = rng.normal(loc=[0, 0, loc], scale=[0.2, 0.2, 0.05], size=[npix, 3])
         tof = sc.linspace('tof', 0, 1.0e5, ntof + 1, unit='us')
         values = rng.normal(loc=5.0e4, scale=2.0e4, size=[npix, ntof])
diff --git a/tests/dream/io/geant4_test.py b/tests/dream/io/geant4_test.py
index 44549c5c..db216eb6 100644
--- a/tests/dream/io/geant4_test.py
+++ b/tests/dream/io/geant4_test.py
@@ -10,7 +10,6 @@
 import sciline
 import scipp as sc
 import scipp.testing
-
 from ess.dream import data, load_geant4_csv
 from ess.powder.types import DetectorName, FilePath, RawDetectorData, SampleRun
 
@@ -27,7 +26,7 @@ def load_file(file_path):
         return archive.read(archive.namelist()[0])
 
 
-@pytest.fixture(scope='function')
+@pytest.fixture()
 def file(load_file):
     return BytesIO(load_file)
 
@@ -58,7 +57,7 @@ def test_load_geant4_csv_loads_expected_structure(file):
 
 
 @pytest.mark.parametrize(
-    'key', ('mantle', 'high_resolution', 'endcap_forward', 'endcap_backward')
+    'key', ['mantle', 'high_resolution', 'endcap_forward', 'endcap_backward']
 )
 def test_load_gean4_csv_set_weights_to_one(file, key):
     detector = load_geant4_csv(file)['instrument'][key]['events']
diff --git a/tests/dream/io/nexus_test.py b/tests/dream/io/nexus_test.py
index 71ba2695..6f7fe5f9 100644
--- a/tests/dream/io/nexus_test.py
+++ b/tests/dream/io/nexus_test.py
@@ -1,11 +1,10 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
 import pytest
-
 from ess import dream
 
 
-@pytest.fixture
+@pytest.fixture()
 def filename():
     return dream.data.get_path('DREAM_nexus_sorted-2023-12-07.nxs')
 
diff --git a/tests/powder/conversion_test.py b/tests/powder/conversion_test.py
index 3ba3d3dc..08af8a77 100644
--- a/tests/powder/conversion_test.py
+++ b/tests/powder/conversion_test.py
@@ -5,7 +5,6 @@
 import scipp as sc
 import scipp.testing
 import scippneutron as scn
-
 from ess.powder.conversion import (
     to_dspacing_with_calibration,
     to_dspacing_with_positions,
diff --git a/tests/powder/correction_test.py b/tests/powder/correction_test.py
index ea3f697e..0f731529 100644
--- a/tests/powder/correction_test.py
+++ b/tests/powder/correction_test.py
@@ -4,11 +4,10 @@
 import pytest
 import scipp as sc
 import scipp.testing
-
 from ess.powder.correction import apply_lorentz_correction, merge_calibration
 
 
-@pytest.fixture
+@pytest.fixture()
 def calibration():
     rng = np.random.default_rng(789236)
     n = 30
@@ -58,7 +57,7 @@ def test_merge_calibration_raises_if_spectrum_mismatch(calibration):
             )
         },
     )
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match='spectrum of calibration and target'):
         merge_calibration(into=da, calibration=calibration)
 
 
@@ -70,7 +69,9 @@ def test_merge_calibration_raises_if_difa_exists(calibration):
             'difa': sc.ones(sizes={'spectrum': calibration.sizes['spectrum']}),
         },
     )
-    with pytest.raises(ValueError):
+    with pytest.raises(
+        ValueError, match='there already is metadata with the same name'
+    ):
         merge_calibration(into=da, calibration=calibration)
 
 
@@ -82,7 +83,9 @@ def test_merge_calibration_raises_if_difc_exists(calibration):
             'difc': sc.ones(sizes={'spectrum': calibration.sizes['spectrum']}),
         },
     )
-    with pytest.raises(ValueError):
+    with pytest.raises(
+        ValueError, match='there already is metadata with the same name'
+    ):
         merge_calibration(into=da, calibration=calibration)
 
 
@@ -94,7 +97,9 @@ def test_merge_calibration_raises_if_tzero_exists(calibration):
             'tzero': sc.ones(sizes={'spectrum': calibration.sizes['spectrum']}),
         },
     )
-    with pytest.raises(ValueError):
+    with pytest.raises(
+        ValueError, match='there already is metadata with the same name'
+    ):
         merge_calibration(into=da, calibration=calibration)
 
 
@@ -108,13 +113,13 @@ def test_merge_calibration_raises_if_mask_exists(calibration):
             'calibration': sc.ones(sizes={'spectrum': calibration.sizes['spectrum']})
         },
     )
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match='there already is a mask with the same name'):
         merge_calibration(into=da, calibration=calibration)
 
 
-@pytest.mark.parametrize('data_dtype', ('float32', 'float64'))
-@pytest.mark.parametrize('dspacing_dtype', ('float32', 'float64'))
-@pytest.mark.parametrize('two_theta_dtype', ('float32', 'float64'))
+@pytest.mark.parametrize('data_dtype', ['float32', 'float64'])
+@pytest.mark.parametrize('dspacing_dtype', ['float32', 'float64'])
+@pytest.mark.parametrize('two_theta_dtype', ['float32', 'float64'])
 def test_lorentz_correction_dense_1d_coords(
     data_dtype, dspacing_dtype, two_theta_dtype
 ):
@@ -204,9 +209,9 @@ def test_apply_lorentz_correction_dense_2d_coord():
         sc.testing.assert_identical(da.coords[key], original.coords[key])
 
 
-@pytest.mark.parametrize('data_dtype', ('float32', 'float64'))
-@pytest.mark.parametrize('dspacing_dtype', ('float32', 'float64'))
-@pytest.mark.parametrize('two_theta_dtype', ('float32', 'float64'))
+@pytest.mark.parametrize('data_dtype', ['float32', 'float64'])
+@pytest.mark.parametrize('dspacing_dtype', ['float32', 'float64'])
+@pytest.mark.parametrize('two_theta_dtype', ['float32', 'float64'])
 def test_apply_lorentz_correction_event_coords(
     data_dtype, dspacing_dtype, two_theta_dtype
 ):
diff --git a/tests/powder/external/powgen/powgen_reduction_test.py b/tests/powder/external/powgen/powgen_reduction_test.py
index 96f59248..64bba88f 100644
--- a/tests/powder/external/powgen/powgen_reduction_test.py
+++ b/tests/powder/external/powgen/powgen_reduction_test.py
@@ -4,7 +4,6 @@
 import pytest
 import sciline
 import scipp as sc
-
 from ess.powder.types import (
     CalibrationFilename,
     DspacingBins,
diff --git a/tests/powder/filtering_test.py b/tests/powder/filtering_test.py
index 3c4b9604..ff357138 100644
--- a/tests/powder/filtering_test.py
+++ b/tests/powder/filtering_test.py
@@ -6,7 +6,6 @@
 
 import numpy as np
 import scipp as sc
-
 from ess.powder import filtering
 
 
diff --git a/tests/powder/load_test.py b/tests/powder/load_test.py
index 069322d6..c93716e9 100644
--- a/tests/powder/load_test.py
+++ b/tests/powder/load_test.py
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
 import pytest
-
 from ess.powder.external import load_calibration
 from ess.powder.external.powgen import data
 
@@ -26,7 +25,7 @@ def test_load_calibration_loads_required_data():
     reason='mantid.LoadDiffCal causes SEGFAULT on CI but seems to work fine elsewhere'
 )
 def test_load_calibration_requires_instrument_definition():
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match='calibration'):
         load_calibration(data.calibration_file())
 
 
@@ -34,7 +33,7 @@ def test_load_calibration_requires_instrument_definition():
     reason='mantid.LoadDiffCal causes SEGFAULT on CI but seems to work fine elsewhere'
 )
 def test_load_calibration_can_only_have_1_instrument_definition():
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match='instrument_name'):
         load_calibration(
             data.calibration_file(),
             instrument_name='POWGEN',
diff --git a/tox.ini b/tox.ini
index 0a5226eb..87e882ee 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,14 +10,14 @@ commands = pytest {posargs}
 
 [testenv:nightly]
 deps = -r requirements/nightly.txt
-commands = pytest
+commands = pytest {posargs}
 
 [testenv:unpinned]
 description = Test with unpinned dependencies, as a user would install now.
 deps =
   -r requirements/basetest.txt
   essdiffraction
-commands = pytest
+commands = pytest {posargs}
 
 [testenv:docs]
 description = invoke sphinx-build to build the HTML docs