diff --git a/.github/workflows/cicd.yml b/.github/workflows/cicd.yml
index 64abdbe..65b0ba5 100644
--- a/.github/workflows/cicd.yml
+++ b/.github/workflows/cicd.yml
@@ -5,10 +5,13 @@ name: Python application
 
 on:
   push:
+    branches: ["main"]
   pull_request:
     branches: ["main"]
   schedule:
     - cron: "0 2 * * 3"
+  release:
+    types: [published]
 
 permissions:
   contents: read
@@ -41,7 +44,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
diff --git a/README.md b/README.md
index 0b2d238..7d6f59b 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,10 @@ You will need to find and replace occurences of
   and [Creative Commons](https://creativecommons.org/chooser/).
   Replace [`LICENSE`](LICENSE) file with the license you choose.
 - Update the `CITATION.cff` file with your information.
+- once you change the code under `src`, please make sure to update
+  - `docs/tutorial/tutorial.ipynb` (add your usage example)
+  - `tests/test_mockup.py` (delete file and add your own tests following the
+    naming conventions `test_<filename>.py`)
 
 ## Development environment
 
@@ -29,6 +33,19 @@ Install package so that new code is picked up in a restared python interpreter:
 pip install -e ".[dev]"
 ```
 
+Then you want to run locally the commands which are check in the CI/CD pipeline 
+(using GitHub Actions). You can type
+
+```bash
+# run unittests
+pytest tests
+# format code and sort imports
+black .
+isort .
+# lint code and check for obvious errors
+ruff check src
+```
+
 ## Basic usage
 
 > works using this template
diff --git a/developing.md b/developing.md
index 4fce3ee..568e867 100644
--- a/developing.md
+++ b/developing.md
@@ -2,14 +2,14 @@
 
 > Author: Henry Webel
 
-[packaging.python.org](https://packaging.python.org/en/latest/tutorials/packaging-projects/) 
+[packaging.python.org](https://packaging.python.org/en/latest/tutorials/packaging-projects/)
 has an excellent tutorial on how to package a Python project. I read and used insights from
 that website to help create the template which is available on GitHub at
 [https://github.com/RasmussenLab/python_package](https://github.com/RasmussenLab/python_package)
 and I want to give here an overview specifically to some details regarding this template.
-Some are overlapping with the 
+Some are overlapping with the
 [packaging.python.org](https://packaging.python.org/en/latest/tutorials/packaging-projects/)
-tutorial, but as always we decided for a certain set of tools, conventions and complexity 
+tutorial, but as always we decided for a certain set of tools, conventions and complexity
 which needs some explanation.
 
 Here a brief overview of external resources you can also look at:
@@ -21,7 +21,7 @@ Here a brief overview of external resources you can also look at:
 
 ## Project structure
 
-First an overview of the main folder structure. See line comments for details on what 
+First an overview of the main folder structure. See line comments for details on what
 is the purpose of each folder or file:
 
 ```bash
@@ -40,20 +40,20 @@ python_package
 
 ## Core packaging files
 
-We will first look at [`pyproject.toml`](pyproject.toml) and its relation to the 
-[`src`](src) directory. The 
+We will first look at [`pyproject.toml`](pyproject.toml) and its relation to the
+[`src`](src) directory. The
 [`pyproject.toml`](pyproject.toml) file is the main configuration file for the Python package
 and is used to specify the package metadata, dependencies, build tools and configurations.
 The [`src`](src) folder stores the actual source code of the package, where the package itself is
-the subdirectories of the [`src`](src) directory. The  (e.g. `src/python_package`).
+the subdirectories of the [`src`](src) directory. The (e.g. `src/python_package`).
 
 <details>
 <summary>About <code>setup.py</code> and <code>setup.cfg</code> configuration files</summary>
 
-The [`setup.py`](setup.py) file is an artefact for backward compatibility and should not 
-be changed.  Everything that used to be in [`setup.py`](setup.py) or 
+The [`setup.py`](setup.py) file is an artefact for backward compatibility and should not
+be changed. Everything that used to be in [`setup.py`](setup.py) or
 [`setup.cfg`](setup.cfg) is now largely in [`pyproject.toml`](pyproject.toml).
-The notable exception would be the desired maximum line length in `setup.cfg` for 
+The notable exception would be the desired maximum line length in `setup.cfg` for
 the tool [`flake8`](https://flake8.pycqa.org/), which does not yet supported
 [`pyproject.toml`](pyproject.toml) configuration. As we use `ruff` as linter,
 we left it empty, but in case you want to use `flake8`, you can add:
@@ -71,12 +71,12 @@ aggressive = 2
 ### Changes required in `pyproject.toml`
 
 You have to change entries under the `[project]` section to match your project name,
-description, author, license, etc. Make sure to pick a license that works for you, e.g. 
+description, author, license, etc. Make sure to pick a license that works for you, e.g.
 using [choosealicense.com](https://choosealicense.com/). Also update the `LICENSE` file
 accordingly.
 
-The `dependencies` key can 
-list the dependencies and is currently commented out. The dependencies could also be 
+The `dependencies` key can
+list the dependencies and is currently commented out. The dependencies could also be
 specified in via a `requirements.txt`, if you already have such a file.
 
 ```toml
@@ -93,7 +93,7 @@ dynamic = ["version", # version is loaded from the package
 #"dependencies", # add if using requirements.txt
 ]
 readme = "README.md"
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 # These are keywords
 classifiers = [
   "Programming Language :: Python :: 3",
@@ -114,13 +114,13 @@ The entry
 dynamic = ["version"]
 ```
 
-means that the version is loaded dynamically using the extension 
+means that the version is loaded dynamically using the extension
 [setuptools_scm](https://setuptools-scm.readthedocs.io/)
-we list under the `[build-system]` section in [`pyproject.toml`](pyproject.toml). 
-This is done to avoid having to manually update the version and integrate with automatic 
+we list under the `[build-system]` section in [`pyproject.toml`](pyproject.toml).
+This is done to avoid having to manually update the version and integrate with automatic
 versioning through releases on GitHub. It also
 ensures that each commit has a unique version number, which is useful for attributing
-errors to specific non-released versions. The dynamic version is picked up in the 
+errors to specific non-released versions. The dynamic version is picked up in the
 `__version__` variable in the `__init__.py` file of the package, which is located in the
 [`src/python_package`](src/python_package) directory.
 
@@ -130,7 +130,7 @@ build-backend = "setuptools.build_meta"
 requires = ["setuptools>=64", "setuptools_scm>=8"]
 
 [tool.setuptools_scm]
-# https://setuptools-scm.readthedocs.io/ 
+# https://setuptools-scm.readthedocs.io/
 # used to pick up the version from the git tags or the latest commit.
 ```
 
@@ -166,12 +166,12 @@ python-package-hello -n 3
 
 ## Source directory layout of the package
 
-The source code of the package is located in the `src` directory, to have a project 
+The source code of the package is located in the `src` directory, to have a project
 independent folder to look for the source code recognized by most tools you would need
-to build a package 
-(read on [packagin namespace packages](https://packaging.python.org/en/latest/guides/packaging-namespace-packages/)). 
-It also allows to have multiple subpackages or modules 
-in the same project under the `python_package` package (see example 
+to build a package
+(read on [packagin namespace packages](https://packaging.python.org/en/latest/guides/packaging-namespace-packages/)).
+It also allows to have multiple subpackages or modules
+in the same project under the `python_package` package (see example
 [here](https://setuptools.pypa.io/en/latest/userguide/package_discovery.html#src-layout)).
 
 ```bash
@@ -181,8 +181,8 @@ in the same project under the `python_package` package (see example
 │       └── mockup.py # a submodule of the package (import python_package.mockup)
 ```
 
-So you will need to rename the `python_package` directory to your package name, 
-e.g. `my_package` and specify the package name in the [`pyproject.toml`](pyproject.toml) file 
+So you will need to rename the `python_package` directory to your package name,
+e.g. `my_package` and specify the package name in the [`pyproject.toml`](pyproject.toml) file
 under the `[project]` section:
 
 ```toml
@@ -191,14 +191,14 @@ name = "my_package"
 
 Strictly speaking you can give different names in both places, but this will only confuse
 potential users. Think of `scikit-learn` for an example of a package that uses a different
-name in the [`pyproject.toml`](pyproject.toml) file and the source code directory name, 
+name in the [`pyproject.toml`](pyproject.toml) file and the source code directory name,
 leading to the `sklearn` package name when imported.
 
 ## Documentation
 
 The documentation is created using [Sphinx](https://www.sphinx-doc.org/en/master/),
 which is common for Python documentation. It relies additionally on several extensions
-enabling the use of `markdown` and `jupyter` notebooks. 
+enabling the use of `markdown` and `jupyter` notebooks.
 
 The documentation is located in the [`docs`](docs) directory. Sphinx is configured via
 the [`conf.py`](docs/conf.py) file, where you can specify the extension you want:
@@ -218,12 +218,12 @@ extensions = [
 ]
 ```
 
-These are added as dependencies through the 
+These are added as dependencies through the
 `pyproject.toml` file under the `[project.optional-dependencies]` section:
 
 ```toml
 [project.optional-dependencies]
-# Optional dependencies to locally build the documentation, also used for 
+# Optional dependencies to locally build the documentation, also used for
 # readthedocs.
 docs = [
   "sphinx",
@@ -273,7 +273,7 @@ package on the fly. See the Read The Docs section below for more details.
 
 We build the documentation based on the template
 [sphinx_book_theme](https://sphinx-book-theme.readthedocs.io), which is set in the
-[`conf.py`](docs/conf.py) file and parts of our docs requirements in 
+[`conf.py`](docs/conf.py) file and parts of our docs requirements in
 [`pyproject.toml`](pyproject.toml):
 
 ```python
@@ -284,12 +284,12 @@ html_theme = "sphinx_book_theme"
 > and need to be changed. Explore other themes here:
 > [sphinx-themes.org](https://sphinx-themes.org/)
 
-The API of the Python package in the `src` directory is automatically included 
+The API of the Python package in the `src` directory is automatically included
 in the documentation using the
 [`autodoc` extension](https://www.sphinx-doc.org/en/master/usage/extensions/autodoc.html).
 We use per default the `numpydoc` style for docstrings, see the format
 [here](https://numpydoc.readthedocs.io/en/stable/format.html).
-The API documentation can be augmented with highlights from other types from projects 
+The API documentation can be augmented with highlights from other types from projects
 using `intersphinx`:
 
 ```python
@@ -308,8 +308,8 @@ like `pandas`, `scikit-learn`, or `matplotlib` to the mapping.
 ### Building the documentation locally (with integration tests)
 
 To build the documentation locally, you can follow the instructions in the
-[`docs/README.md`](docs/README.md), which you should also update with your name changes. 
-In short, you can run the following commands in the [`docs`](docs ) directory:
+[`docs/README.md`](docs/README.md), which you should also update with your name changes.
+In short, you can run the following commands in the [`docs`](docs) directory:
 
 ```bash
 # in root of the project
@@ -321,10 +321,10 @@ sphinx-build -n -W --keep-going -b html ./ ./_build/
 
 this will create a `reference` directory with the API documentation of the Python package
 `python_package`, a `jupyter_execute` for the tutorial in [`docs/tutorial`](docs/tutorial)
- and a `_build` directory with an HTML version of the documentation. You can open the
+and a `_build` directory with an HTML version of the documentation. You can open the
 `_build/index.html` file in your browser to view the documentation built locally.
 
-The tutorial related configuration in `conf.py` is the following, specifying that 
+The tutorial related configuration in `conf.py` is the following, specifying that
 errors stop the build process ensuring that examples are tested:
 
 ```python
@@ -348,22 +348,22 @@ nb_merge_streams = True
 
 The tutorials are meant as a sort of integration test, where you make sure that the core
 functionality your project wants to support is working as expected. For easier github
-diffs, we use [`jupytext`](https://jupytext.readthedocs.io), which allows to 
-have the tutorial in both a Jupyter Notebook format and a Python script format. 
+diffs, we use [`jupytext`](https://jupytext.readthedocs.io), which allows to
+have the tutorial in both a Jupyter Notebook format and a Python script format.
 You have to keep the files in sync using:
 
 ```bash
 jupytext --sync docs/tutorial/*.ipynb
 ```
 
-The [`docs/tutorial/.jupytext`](docs/tutorial/.jupytext) configuration sets the default 
+The [`docs/tutorial/.jupytext`](docs/tutorial/.jupytext) configuration sets the default
 format to `py:percent` and automatically allows syncing of new notebooks.
 
 ### Read The Docs
 
 To build the documentation on Read The Docs, you need to create a file called
-[`.readthedocs.yaml`](.readthedocs.yaml), which is located in the root of the project and 
-specifies which dependencies are needed. The core is the following specifying where the 
+[`.readthedocs.yaml`](.readthedocs.yaml), which is located in the root of the project and
+specifies which dependencies are needed. The core is the following specifying where the
 [`conf.py`](docs/conf.py) file is and from where to install the required dependencies:
 
 ```yaml
@@ -379,20 +379,20 @@ python:
         - docs
 ```
 
-You will need to manually register your project repository on 
+You will need to manually register your project repository on
 [Read The Docs](https://readthedocs.org/) in order that it can build the documentation
-by the service. I recommend to activate builds for Pull Requests, so that 
-the documentation is built for each PR and you can see if the documentation is gradually 
+by the service. I recommend to activate builds for Pull Requests, so that
+the documentation is built for each PR and you can see if the documentation is gradually
 breaking, i.e. your integration test using the notebooks in
 [`docs/tutorial`](docs/tutorial) fail. See their documentation
-[on adding a project](https://docs.readthedocs.com/platform/stable/intro/add-project.html) 
+[on adding a project](https://docs.readthedocs.com/platform/stable/intro/add-project.html)
 for instructions.
 
 ## Running tests
 
 The tests are located in the `tests` directory and can be run using `pytest`.
 Pytest is specified as a dependency in the `pyproject.toml` file under the
-`[project.optional-dependencies]` section along with the formatter `black` and the 
+`[project.optional-dependencies]` section along with the formatter `black` and the
 linter `ruff`:
 
 ```toml
@@ -414,7 +414,7 @@ read the next section to see how this is automated using `GitHub Actions`.
 ## GitHub Actions
 
 We run these checks also on GitHub using GitHub Actions. The configuration
-for the actions is located in the [`.github/workflows`](.github/workflows) directory 
+for the actions is located in the [`.github/workflows`](.github/workflows) directory
 and is specified in the `cdci.yml` file. See the biosustain dsp tutorial on GitHub Actions
 for more details (or any other resource you find):
 [biosustain/dsp_actions_tutorial](https://github.com/biosustain/dsp_actions_tutorial)
@@ -427,10 +427,13 @@ name: Python application
 
 on:
   push:
+    branches: ["main"]
   pull_request:
     branches: ["main"]
   schedule:
     - cron: "0 2 * * 3"
+  release:
+    types: [published]
 
 permissions:
   contents: read
@@ -462,7 +465,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.11", "3.12"]
+        python-version: ["3.9", "3.11", "3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
@@ -480,42 +483,42 @@ jobs:
         run: python -m pytest tests
 ```
 
-This workflow also allows to create `PyPI` releases automatically if you register your 
+This workflow also allows to create `PyPI` releases automatically if you register your
 project on `PyPI` (or `TestPyPI` for testing first) and create a GitHub release:
 
 ```yaml
-  publish:
-    name: Publish package
-    if: startsWith(github.ref, 'refs/tags')
-    needs:
-      - format
-      - lint
-      - test
-      - build_source_dist
-      # - build_wheels
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/download-artifact@v4
-        with:
-          name: artifact
-          path: ./dist
-
-      - uses: pypa/gh-action-pypi-publish@release/v1
-        with:
-          # remove repository key to set the default to pypi (not test.pypi.org)
-          repository-url: https://test.pypi.org/legacy/
+publish:
+  name: Publish package
+  if: startsWith(github.ref, 'refs/tags')
+  needs:
+    - format
+    - lint
+    - test
+    - build_source_dist
+    # - build_wheels
+  runs-on: ubuntu-latest
+
+  steps:
+    - uses: actions/download-artifact@v4
+      with:
+        name: artifact
+        path: ./dist
+
+    - uses: pypa/gh-action-pypi-publish@release/v1
+      with:
+        # remove repository key to set the default to pypi (not test.pypi.org)
+        repository-url: https://test.pypi.org/legacy/
 ```
 
 To setup the [`gh-action-pypi-publish`](https://github.com/pypa/gh-action-pypi-publish)
 action, you need to register the repository
-on [PyPI](https://pypi.org/) or [`TestPyPI`](https://test.pypi.org/), which allows PyPI 
+on [PyPI](https://pypi.org/) or [`TestPyPI`](https://test.pypi.org/), which allows PyPI
 and GitHub to communicate securely. See the instructions on
 [packaging.python.org](https://packaging.python.org/en/latest/guides/publishing-package-distribution-releases-using-github-actions-ci-cd-workflows/).
 
 You then trigger new releases to PyPI by creating a new GitHub release, which will
 automatically trigger the `publish` job in the workflow as it needs you to set a tag.
-Have a look at [VueGen Releases]( https://github.com/Multiomics-Analytics-Group/vuegen/releases)
+Have a look at [VueGen Releases](https://github.com/Multiomics-Analytics-Group/vuegen/releases)
 for an example. The release notes are automatically generated using the PR titles,
 see GitHub's
 [docs](https://docs.github.com/en/repositories/releasing-projects-on-github/automatically-generated-release-notes).
@@ -528,31 +531,30 @@ to be partly compiled, e.g. if you use `Cython`, `numpy` C extensions or Rust ex
 Also additionally you could use the artifact from the `build_source_dist` job
 to test the build of the source distribution. This is useful to ensure that a package
 with non-Python files (e.g. data files) is built correctly and that the package
-can be installed correctly. You should probably best test this in as much isolation as 
+can be installed correctly. You should probably best test this in as much isolation as
 you can, e.g. by not pulling the repository using `actions/checkout@v4`.
 
 ```yaml
-  test_sdist:
-    name: Install built source distribution
-    needs: build_source_dist
-    runs-on: ubuntu-latest
-    steps:
-      # - uses: actions/checkout@v4 
-      - uses: actions/download-artifact@v4
-        with:
-          name: artifact
-          path: ./dist
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.11"
-      - name: Install built sdist
-        run: |
-          pip install ./dist/*.tar.gz
-      # ... some checks
+test_sdist:
+  name: Install built source distribution
+  needs: build_source_dist
+  runs-on: ubuntu-latest
+  steps:
+    # - uses: actions/checkout@v4
+    - uses: actions/download-artifact@v4
+      with:
+        name: artifact
+        path: ./dist
+    - uses: actions/setup-python@v5
+      with:
+        python-version: "3.11"
+    - name: Install built sdist
+      run: |
+        pip install ./dist/*.tar.gz
+    # ... some checks
 ```
-</details>
-
 
+</details>
 
 ## Full project structure
 
diff --git a/pyproject.toml b/pyproject.toml
index ec501b0..595531f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,7 +10,7 @@ dynamic = [
   #"dependencies", # add if using requirements.txt
 ]
 readme = "README.md"
-requires-python = ">=3.9" # test all higher Python versions
+requires-python = ">=3.10" # test all higher Python versions
 # These are keywords
 classifiers = [
   "Programming Language :: Python :: 3",