diff --git a/.gitignore b/.gitignore
index 1962da0..ec4cfe6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -44,6 +44,7 @@ coverage.xml
 *.cover
 *.py,cover
 .pytest_cache/
+pytest.xml
 
 # Translations
 *.mo
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 43c130e..a25937d 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -7,7 +7,7 @@
 
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.11.0
+    rev: v0.11.13
     hooks:
       - id: ruff
         args:
@@ -29,6 +29,10 @@ repos:
     hooks:
       - id: codespell
         additional_dependencies: [tomli]
+  - repo: https://github.com/gitleaks/gitleaks
+    rev: v8.21.2
+    hooks:
+      - id: gitleaks
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v5.0.0
     hooks:
@@ -85,4 +89,8 @@ repos:
           - --max-average=B
           - --max-modules=B
           - --max-absolute=C
+  - repo: https://github.com/rbubley/mirrors-prettier
+    rev: v3.3.3
+    hooks:
+      - id: prettier
 exclude: '\.nc$|^tests/fixture/|\.ipynb$'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c09226..ca0fb7d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -136,7 +136,7 @@
 
 **Implemented enhancements:**
 
-- Add a command-line interface  [\#82](https://github.com/btschwertfeger/python-cmethods/issues/82)
+- Add a command-line interface [\#82](https://github.com/btschwertfeger/python-cmethods/issues/82)
 - Resolve "Add a command-line interface" [\#83](https://github.com/btschwertfeger/python-cmethods/pull/83) ([btschwertfeger](https://github.com/btschwertfeger))
 
 **Merged pull requests:**
@@ -175,7 +175,7 @@
 
 **Closed issues:**
 
-- The latest documentation still describes the legacy max\_scaling\_factor [\#60](https://github.com/btschwertfeger/python-cmethods/issues/60)
+- The latest documentation still describes the legacy max_scaling_factor [\#60](https://github.com/btschwertfeger/python-cmethods/issues/60)
 
 **Merged pull requests:**
 
@@ -223,7 +223,7 @@
 
 **Merged pull requests:**
 
-- Clarified difference between stochastic and non-stochastic climate variables in doc and readme  [\#36](https://github.com/btschwertfeger/python-cmethods/pull/36) ([btschwertfeger](https://github.com/btschwertfeger))
+- Clarified difference between stochastic and non-stochastic climate variables in doc and readme [\#36](https://github.com/btschwertfeger/python-cmethods/pull/36) ([btschwertfeger](https://github.com/btschwertfeger))
 - Fix typos [\#38](https://github.com/btschwertfeger/python-cmethods/pull/38) ([btschwertfeger](https://github.com/btschwertfeger))
 
 ## [v1.0.1](https://github.com/btschwertfeger/python-cmethods/tree/v1.0.1) (2023-04-17)
@@ -237,7 +237,7 @@
 
 **Fixed bugs:**
 
-- Multiplicative Quantile Delta Mapping is not applying scaling where the delta is infinite  [\#32](https://github.com/btschwertfeger/python-cmethods/issues/32)
+- Multiplicative Quantile Delta Mapping is not applying scaling where the delta is infinite [\#32](https://github.com/btschwertfeger/python-cmethods/issues/32)
 - Fixed PyPI repository URL [\#16](https://github.com/btschwertfeger/python-cmethods/pull/16) ([btschwertfeger](https://github.com/btschwertfeger))
 - Fixed bug where division lead to nan or inf values [\#33](https://github.com/btschwertfeger/python-cmethods/pull/33) ([btschwertfeger](https://github.com/btschwertfeger))
 
@@ -257,7 +257,7 @@
 
 **Breaking changes:**
 
-- Remove the unnecessary `CMethods.py` module to access the CMethods  class more easily [\#10](https://github.com/btschwertfeger/python-cmethods/issues/10)
+- Remove the unnecessary `CMethods.py` module to access the CMethods class more easily [\#10](https://github.com/btschwertfeger/python-cmethods/issues/10)
 
 **Implemented enhancements:**
 
@@ -282,7 +282,7 @@
 
 **Breaking changes:**
 
-- adjust\_3d forces group to be "time.month" if group is set to the default \(None\) [\#5](https://github.com/btschwertfeger/python-cmethods/issues/5)
+- adjust_3d forces group to be "time.month" if group is set to the default \(None\) [\#5](https://github.com/btschwertfeger/python-cmethods/issues/5)
 
 **Implemented enhancements:**
 
@@ -340,6 +340,4 @@
 
 [Full Changelog](https://github.com/btschwertfeger/python-cmethods/compare/41c1837e5d23c300656c8ee2ce0079d6a8baac2f...v0.5)
 
-
-
-\* *This Changelog was automatically generated by [github_changelog_generator](https://github.com/github-changelog-generator/github-changelog-generator)*
+\* _This Changelog was automatically generated by [github_changelog_generator](https://github.com/github-changelog-generator/github-changelog-generator)_
diff --git a/Makefile b/Makefile
index 0055886..52cad40 100644
--- a/Makefile
+++ b/Makefile
@@ -6,35 +6,47 @@
 # https://github.com/btschwertfeger
 #
 
-VENV := venv
+UV := uv
 PYTHON := python
+PYTEST := $(UV) run pytest
 TESTS := tests
-PYTEST_OPTS := -vv
-ROOT_DIR:=$(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
+PYTEST_OPTS := -vv --junit-xml=pytest.xml
+PYTEST_COV_OPTS := $(PYTEST_OPTS) --cov=cmethods --cov-report=xml:coverage.xml --cov-report=term
 
+## ======= M A K E F I L E - T A R G E T S =====================================
+## help           Show this help message
+##
 .PHONY: help
 help:
 	@grep "^##" Makefile | sed -e "s/##//"
 
-## build		Builds python-cmethods
+## ======= B U I L D I N G =====================================================
+## build		Builds the package
 ##
 .PHONY: build
 build:
 	$(PYTHON) -m build .
 
+## rebuild 	Rebuild the package
+##
+.PHONY: rebuild
+rebuild: clean build
+
+## ======= I N S T A L L A T I O N =============================================
+## install	Install the package
+##
+.PHONY: install
+install: check-uv
+	$(UV) pip install .
+
 ## dev		Installs the package in edit mode
 ##
 .PHONY: dev
 dev:
 	@git lfs install
-	$(PYTHON) -m pip install -e ".[dev,test,jupyter,examples]" -r doc/requirements.txt
-
-## install		Install the package
-##
-.PHONY: install
-install:
-	$(PYTHON) -m pip install .
+	$(UV) pip install -e ".[dev,test,jupyter,examples]" -r doc/requirements.txt
 
+## ======= T E S T I N G =======================================================
 ## test		Run the unit tests
 ##
 .PHONY: test
@@ -50,13 +62,18 @@ tests: test
 retest:
 	$(PYTHON) -m pytest $(PYTEST_OPTS) --lf $(TESTS)
 
-
 ## wip  	Run tests marked as wip
 ##
 .PHONY: wip
 wip:
 	$(PYTHON) -m pytest $(PYTEST_OPTS) -m "wip" $(TESTS)
 
+## coverage       Run all tests and generate the coverage report
+##
+.PHONY: coverage
+coverage:
+	$(PYTEST) $(PYTEST_COV_OPTS) $(TEST_DIR)
+
 ## doc		Build the documentation
 ##
 .PHONY: doc
@@ -69,7 +86,8 @@ doc:
 doctest:
 	cd doc && make doctest
 
-## pre-commit		Pre-Commit
+## ======= M I S C E L A N I O U S =============================================
+## pre-commit	Run the pre-commit targets
 ##
 .PHONY: pre-commit
 pre-commit:
@@ -92,7 +110,7 @@ ruff-fix:
 .PHONY: changelog
 changelog:
 	docker run -it --rm \
-		-v $(ROOT_DIR):/usr/local/src/your-app/ \
+		-v $(PWD):/usr/local/src/your-app/ \
 		githubchangeloggenerator/github-changelog-generator \
 		-u btschwertfeger \
 		-p python-cmethods \
@@ -115,3 +133,12 @@ clean:
 	find tests -name "__pycache__" | xargs rm -rf
 	find cmethods -name "__pycache__" | xargs rm -rf
 	find examples -name "__pycache__" | xargs rm -rf
+
+## check-uv       Check if uv is installed
+##
+.PHONY: check-uv
+check-uv:
+	@if ! command -v $(UV) >/dev/null; then \
+		echo "Error: uv is not installed. Please visit https://github.com/astral-sh/uv for installation instructions."; \
+		exit 1; \
+	fi
diff --git a/cmethods/__init__.py b/cmethods/__init__.py
index 87eacb1..2778b2e 100644
--- a/cmethods/__init__.py
+++ b/cmethods/__init__.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 # pylint: disable=consider-using-f-string,logging-not-lazy
 
 r"""
diff --git a/cmethods/core.py b/cmethods/core.py
index 3c5996f..714b51b 100644
--- a/cmethods/core.py
+++ b/cmethods/core.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2024 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """
 Module providing the main function that is used to apply the implemented bias
diff --git a/cmethods/distribution.py b/cmethods/distribution.py
index 14737c3..b66ac6f 100644
--- a/cmethods/distribution.py
+++ b/cmethods/distribution.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2024 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """
 Module providing functions for distribution-based bias adjustments. Functions are not
diff --git a/cmethods/scaling.py b/cmethods/scaling.py
index 766231b..88dd165 100644
--- a/cmethods/scaling.py
+++ b/cmethods/scaling.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2024 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """
 Module providing functions for scaling-based bias adjustments. Functions are not
diff --git a/cmethods/static.py b/cmethods/static.py
index cb311ab..5e52cbb 100644
--- a/cmethods/static.py
+++ b/cmethods/static.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """Module providing static information for the python-cmethods package"""
 
diff --git a/cmethods/types.py b/cmethods/types.py
index c670699..99dd322 100644
--- a/cmethods/types.py
+++ b/cmethods/types.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """Module providing custom types"""
 
diff --git a/cmethods/utils.py b/cmethods/utils.py
index 81f27f9..f675d92 100644
--- a/cmethods/utils.py
+++ b/cmethods/utils.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 
 """Module providing utility functions"""
 
diff --git a/doc/cli.rst b/doc/cli.rst
index e05557e..2e592b3 100644
--- a/doc/cli.rst
+++ b/doc/cli.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Command-Line Interface
 ======================
diff --git a/doc/cmethods.rst b/doc/cmethods.rst
index 65375da..6a5d63e 100644
--- a/doc/cmethods.rst
+++ b/doc/cmethods.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Classes and Functions
 =====================
diff --git a/doc/conf.py b/doc/conf.py
index 5e8ccfa..f2650f8 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -1,9 +1,22 @@
 # -*- mode: python; coding: utf-8 -*-
 #
 # Copyright (C) 2023 Benjamin Thomas Schwertfeger
-# All rights reserved.
 # https://github.com/btschwertfeger
 #
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see
+# https://www.gnu.org/licenses/gpl-3.0.html.
+#
 # Configuration file for the Sphinx documentation builder.
 #
 # For the full list of built-in configuration values, see the documentation:
diff --git a/doc/getting_started.rst b/doc/getting_started.rst
index 2548f8d..7233077 100644
--- a/doc/getting_started.rst
+++ b/doc/getting_started.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Getting Started
 ===============
diff --git a/doc/index.rst b/doc/index.rst
index f2b4759..9ad1387 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Welcome to python-cmethods's documentation!
 ===========================================
diff --git a/doc/introduction.rst b/doc/introduction.rst
index 9dec6ae..fa076ab 100644
--- a/doc/introduction.rst
+++ b/doc/introduction.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 python-cmethods
 ===============
diff --git a/doc/issues.rst b/doc/issues.rst
index 6c150f4..98e78e2 100644
--- a/doc/issues.rst
+++ b/doc/issues.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Known Issues
 ============
diff --git a/doc/license.rst b/doc/license.rst
index 9245eea..e60358b 100644
--- a/doc/license.rst
+++ b/doc/license.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 .. _section-license:
 
diff --git a/doc/links.rst b/doc/links.rst
index c2de0ab..520b64b 100644
--- a/doc/links.rst
+++ b/doc/links.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 .. LINKS
 
diff --git a/doc/methods.rst b/doc/methods.rst
index 6316532..5eb8a41 100644
--- a/doc/methods.rst
+++ b/doc/methods.rst
@@ -1,9 +1,22 @@
 .. -*- mode: rst; coding: utf-8 -*-
 ..
 .. Copyright (C) 2023 Benjamin Thomas Schwertfeger
-.. All rights reserved.
 .. https://github.com/btschwertfeger
 ..
+.. This program is free software: you can redistribute it and/or modify
+.. it under the terms of the GNU General Public License as published by
+.. the Free Software Foundation, either version 3 of the License, or
+.. (at your option) any later version.
+..
+.. This program is distributed in the hope that it will be useful,
+.. but WITHOUT ANY WARRANTY; without even the implied warranty of
+.. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+.. GNU General Public License for more details.
+..
+.. You should have received a copy of the GNU General Public License
+.. along with this program. If not, see
+.. https://www.gnu.org/licenses/gpl-3.0.html.
+..
 
 Bias Correction Methods
 =======================
diff --git a/pyproject.toml b/pyproject.toml
index 9d8dc56..bf40e63 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,6 +20,7 @@ maintainers = [
 ]
 description = "A collection of bias correction techniques written in Python - for climate sciences."
 readme = "README.md"
+license = "GPL-3.0-or-later"
 license-files = ["LICENSE"]
 requires-python = ">=3.9"
 dependencies = [
@@ -62,15 +63,16 @@ classifiers = [
 cmethods = "cmethods:cli"
 
 [project.urls]
-"Homepage" = "https://github.com/btschwertfeger/python-cmethods"
+Homepage = "https://github.com/btschwertfeger/python-cmethods"
 "Bug Tracker" = "https://github.com/btschwertfeger/python-cmethods/issues"
+Documentation = "https://python-cmethods.readthedocs.io/en/stable/"
 
 [tool.setuptools]
 include-package-data = false
 
 [tool.setuptools.packages.find]
 include = ["cmethods*"]
-exclude = ["doc*", "tests*", "examples*", ".env", "venv"]
+exclude = ["doc*", "tests*", "examples*", ".env", ".venv"]
 
 [tool.setuptools_scm]
 write_to = "cmethods/_version.py"
@@ -83,7 +85,10 @@ testpaths = ["tests"]
 
 [tool.pytest.ini_options]
 cache_dir = ".cache/pytest"
-markers = ["wip: Used to run a specific test by hand."]
+markers = [
+  "wip: Used to run a specific test by hand.",
+  "flaky: Use to retry flaky tests",
+]
 addopts = "--maxfail=1"
 
 [tool.coverage.run]
@@ -200,6 +205,7 @@ lint.select = [
   "BLE",   # blind-except
   "C4",    # flake8-comprehensions
   "COM",   # flake8-commas
+  "CPY",    # flake8-copyright
   "E",     # pycodestyle
   "F",     # pyflakes
   "FA",    # flake8-future-annotations
@@ -255,6 +261,11 @@ line-length = 130
 cache-dir = ".cache/ruff"
 lint.task-tags = ["todo", "TODO"]
 
+[tool.ruff.lint.flake8-copyright]
+author = "Benjamin Thomas Schwertfeger"
+notice-rgx = "(?i)Copyright \\(C\\) \\d{4}"
+min-file-size = 1024
+
 [tool.ruff.lint.per-file-ignores]
 "cmethods/types.py" = [
   "A005", # Shadowing builtin
diff --git a/tests/conftest.py b/tests/conftest.py
index 9ac47ad..2f004aa 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -10,7 +10,6 @@
 from __future__ import annotations
 
 import os
-from functools import lru_cache
 from typing import Any
 
 import pytest
@@ -65,7 +64,6 @@ def datasets() -> dict:
     }
 
 
-@lru_cache(maxsize=None)
 @pytest.fixture
 def datasets_from_zarr() -> dict:
     return {
diff --git a/tests/test_methods_different_input_shape.py b/tests/test_methods_different_input_shape.py
index 9eef638..dac9217 100644
--- a/tests/test_methods_different_input_shape.py
+++ b/tests/test_methods_different_input_shape.py
@@ -21,7 +21,9 @@
 
 from .helper import is_1d_rmse_better
 
-N_QUANTILES = 100
+pytestmark = [pytest.mark.flaky]
+
+N_QUANTILES: int = 100
 
 
 @pytest.mark.parametrize(
diff --git a/tests/test_zarr_dask_compatibility.py b/tests/test_zarr_dask_compatibility.py
index ef91a9a..6d5e1bb 100644
--- a/tests/test_zarr_dask_compatibility.py
+++ b/tests/test_zarr_dask_compatibility.py
@@ -15,6 +15,8 @@
 
 from .helper import is_3d_rmse_better
 
+pytestmark = [pytest.mark.flaky]
+
 GROUP: str = "time.month"
 N_QUANTILES: int = 100