diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..bdd2c9b
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,17 @@
+root = true
+
+[*]
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+indent_style = tab
+indent_size = 4
+
+[{*.yaml,*.yml,*.neon,*.json}]
+indent_size = 2
+indent_style = space
+
+[*.md]
+indent_style = space
+max_line_length = 100
diff --git a/.gitattributes b/.gitattributes
index 7a6aaab..2935763 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,4 +1,6 @@
-.github
+* text=auto
+
+.editorconfig export-ignore
 .gitattributes export-ignore
 .github export-ignore
 .gitignore export-ignore
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 96968b1..aef62d4 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -7,15 +7,15 @@ on:
 jobs:
   phpunit:
     name: phpunit
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       matrix:
         php-version:
-        - "7.3"
-        - "8.1"
+        - "8.2"
+        - "8.3"
     steps:
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v4
     - name: Install PHP
       uses: shivammathur/setup-php@v2
       with:
@@ -24,7 +24,7 @@ jobs:
         ini-values: memory_limit=-1
         tools: composer:v2
     - name: Cache dependencies
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: |
           ~/.composer/cache
@@ -39,7 +39,7 @@ jobs:
       run: make test-coveralls
 
     - name: Upload code coverage
-      if: ${{ matrix.php-version == '7.3' }}
+      if: ${{ matrix.php-version == '8.3' }}
       env:
         COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       run: |
diff --git a/.scrutinizer.yml b/.scrutinizer.yml
new file mode 100644
index 0000000..dd7f4e0
--- /dev/null
+++ b/.scrutinizer.yml
@@ -0,0 +1,12 @@
+build:
+  nodes:
+    analysis:
+      tests:
+        override:
+        - php-scrutinizer-run
+  environment:
+    php:
+      version: "8.2"
+filter:
+  excluded_paths:
+  - 'tests/*'
diff --git a/MIGRATION.md b/CHANGELOG.md
similarity index 59%
rename from MIGRATION.md
rename to CHANGELOG.md
index 403610e..1aadc7b 100644
--- a/MIGRATION.md
+++ b/CHANGELOG.md
@@ -1,6 +1,30 @@
-# Migration
+# CHANGELOG
 
-## v1.x to v2.x
+## v2.x to v3.0
+
+### New Requirements
+
+Requires PHP 8.2+
+
+### New features
+
+None
+
+### Backward Incompatible Changes
+
+None
+
+### Deprecated Features
+
+None
+
+### Other Changes
+
+None
+
+
+
+## v1.x to v2.0
 
 ### New Requirements
 
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..5ef93b0
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,132 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+We as members, contributors, and leaders pledge to make participation in our
+community a harassment-free experience for everyone, regardless of age, body
+size, visible or invisible disability, ethnicity, sex characteristics, gender
+identity and expression, level of experience, education, socio-economic status,
+nationality, personal appearance, race, caste, color, religion, or sexual identity
+and orientation.
+
+We pledge to act and interact in ways that contribute to an open, welcoming,
+diverse, inclusive, and healthy community.
+
+## Our Standards
+
+Examples of behavior that contributes to a positive environment for our
+community include:
+
+* Demonstrating empathy and kindness toward other people
+* Being respectful of differing opinions, viewpoints, and experiences
+* Giving and gracefully accepting constructive feedback
+* Accepting responsibility and apologizing to those affected by our mistakes,
+  and learning from the experience
+* Focusing on what is best not just for us as individuals, but for the
+  overall community
+
+Examples of unacceptable behavior include:
+
+* The use of sexualized language or imagery, and sexual attention or
+  advances of any kind
+* Trolling, insulting or derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or email
+  address, without their explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Enforcement Responsibilities
+
+Community leaders are responsible for clarifying and enforcing our standards of
+acceptable behavior and will take appropriate and fair corrective action in
+response to any behavior that they deem inappropriate, threatening, offensive,
+or harmful.
+
+Community leaders have the right and responsibility to remove, edit, or reject
+comments, commits, code, wiki edits, issues, and other contributions that are
+not aligned to this Code of Conduct, and will communicate reasons for moderation
+decisions when appropriate.
+
+## Scope
+
+This Code of Conduct applies within all community spaces, and also applies when
+an individual is officially representing the community in public spaces.
+Examples of representing our community include using an official e-mail address,
+posting via an official social media account, or acting as an appointed
+representative at an online or offline event.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported to the community leaders responsible for enforcement at
+<olivier.laviale@gmail.com>.
+All complaints will be reviewed and investigated promptly and fairly.
+
+All community leaders are obligated to respect the privacy and security of the
+reporter of any incident.
+
+## Enforcement Guidelines
+
+Community leaders will follow these Community Impact Guidelines in determining
+the consequences for any action they deem in violation of this Code of Conduct:
+
+### 1. Correction
+
+**Community Impact**: Use of inappropriate language or other behavior deemed
+unprofessional or unwelcome in the community.
+
+**Consequence**: A private, written warning from community leaders, providing
+clarity around the nature of the violation and an explanation of why the
+behavior was inappropriate. A public apology may be requested.
+
+### 2. Warning
+
+**Community Impact**: A violation through a single incident or series
+of actions.
+
+**Consequence**: A warning with consequences for continued behavior. No
+interaction with the people involved, including unsolicited interaction with
+those enforcing the Code of Conduct, for a specified period of time. This
+includes avoiding interactions in community spaces as well as external channels
+like social media. Violating these terms may lead to a temporary or
+permanent ban.
+
+### 3. Temporary Ban
+
+**Community Impact**: A serious violation of community standards, including
+sustained inappropriate behavior.
+
+**Consequence**: A temporary ban from any sort of interaction or public
+communication with the community for a specified period of time. No public or
+private interaction with the people involved, including unsolicited interaction
+with those enforcing the Code of Conduct, is allowed during this period.
+Violating these terms may lead to a permanent ban.
+
+### 4. Permanent Ban
+
+**Community Impact**: Demonstrating a pattern of violation of community
+standards, including sustained inappropriate behavior,  harassment of an
+individual, or aggression toward or disparagement of classes of individuals.
+
+**Consequence**: A permanent ban from any sort of public interaction within
+the community.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage],
+version 2.0, available at
+[https://www.contributor-covenant.org/version/2/0/code_of_conduct.html][v2.0].
+
+Community Impact Guidelines were inspired by
+[Mozilla's code of conduct enforcement ladder][Mozilla CoC].
+
+For answers to common questions about this code of conduct, see the FAQ at
+[https://www.contributor-covenant.org/faq][FAQ]. Translations are available
+at [https://www.contributor-covenant.org/translations][translations].
+
+[homepage]: https://www.contributor-covenant.org
+[v2.0]: https://www.contributor-covenant.org/version/2/0/code_of_conduct.html
+[Mozilla CoC]: https://github.com/mozilla/diversity
+[FAQ]: https://www.contributor-covenant.org/faq
+[translations]: https://www.contributor-covenant.org/translations
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ed6eaf4..33bc016 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -2,11 +2,13 @@
 
 Contributions are **welcome** and will be fully **credited**.
 
-We accept contributions via Pull Requests on [Github](https://github.com/ICanBoogie/Inflector).
+We accept contributions via Pull Requests.
 
 ## Pull Requests
 
-- **Add tests!** — Your contribution won't be accepted if it doesn't have tests.
+- **Code style** — We're following a [Coding Standard][]. Check the code style with `make lint`.
+- **Code health** — We're using [PHPStan][] to analyse the code, with maximum scrutiny. Check the code with `make lint`.
+- **Add tests!** — Your contribution won't be accepted if it does not have tests.
 - **Document any change in behaviour** — Make sure the `README.md` and any other relevant documentation are kept
   up-to-date.
 - **Consider our release cycle** — We follow [SemVer v2.0.0](http://semver.org/). Randomly breaking public APIs is not
@@ -25,4 +27,6 @@ coverage. The coverage report is available in `build/coverage/index.html`.
 **Thanks for your contribution**!
 
 
+[Coding Standard]: phpcs.xml
 [git-squash]: http://www.git-scm.com/book/en/v2/Git-Tools-Rewriting-History#Changing-Multiple-Commit-Messages
+[PHPStan]: https://phpstan.org/user-guide/getting-started
diff --git a/Dockerfile b/Dockerfile
index f2e62ad..eccf687 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,18 +1,38 @@
-ARG PHP_VERSION
-FROM php:${PHP_VERSION}-cli-alpine
+ARG PHP_VERSION=8.2
+FROM php:${PHP_VERSION}-cli-bookworm
 
-RUN apk add --no-cache make && \
-    docker-php-ext-enable opcache && \
-    docker-php-source delete
+RUN <<-EOF
+    apt-get update
+	apt-get install -y autoconf pkg-config
+	pecl channel-update pecl.php.net
+	pecl install xdebug
+    docker-php-ext-enable opcache xdebug
+EOF
 
-RUN echo $'\
-display_errors=On\n\
-error_reporting=E_ALL\n\
-date.timezone=UTC\n\
-' >> /usr/local/etc/php/conf.d/php.ini
+RUN <<-EOF
+	cat <<-SHELL >> /usr/local/etc/php/conf.d/docker-php-ext-xdebug.ini
+	xdebug.client_host=host.docker.internal
+	xdebug.mode=develop
+	xdebug.start_with_request=yes
+	SHELL
+
+	cat <<-SHELL >> /usr/local/etc/php/conf.d/php.ini
+	display_errors=On
+	error_reporting=E_ALL
+	date.timezone=UTC
+	SHELL
+EOF
 
 ENV COMPOSER_ALLOW_SUPERUSER 1
 
-RUN curl -s https://raw.githubusercontent.com/composer/getcomposer.org/76a7060ccb93902cd7576b67264ad91c8a2700e2/web/installer | php -- --quiet && \
-    mv composer.phar /usr/local/bin/composer && \
-    echo $'export PATH="$HOME/.composer/vendor/bin:$PATH"\n' >> /root/.profile
+RUN <<-EOF
+	apt-get update
+	apt-get install unzip
+	curl -s https://raw.githubusercontent.com/composer/getcomposer.org/76a7060ccb93902cd7576b67264ad91c8a2700e2/web/installer | php -- --quiet
+	mv composer.phar /usr/local/bin/composer
+	cat <<-SHELL >> /root/.bashrc
+	export PATH="$HOME/.composer/vendor/bin:$PATH"
+	SHELL
+EOF
+
+RUN composer global require squizlabs/php_codesniffer
diff --git a/LICENSE b/LICENSE
index 19db9f1..edfca52 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,7 +1,7 @@
 The ICanBoogie/DateTime package is free software.
 It is released under the terms of the following BSD License.
 
-Copyright (c) 2013-2022 by Olivier Laviale
+Copyright (c) 2013 by Olivier Laviale
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without modification,
diff --git a/Makefile b/Makefile
index 8d148f4..17fb4ce 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,5 @@
 # customization
 
-PACKAGE_NAME = ICanBoogie/DateTime
 PHPUNIT = vendor/bin/phpunit
 
 # do not edit the following lines
@@ -15,7 +14,7 @@ test-dependencies: vendor
 
 .PHONY: test
 test: test-dependencies
-	@$(PHPUNIT)
+	@$(PHPUNIT) $(ARGS)
 
 .PHONY: test-coverage
 test-coverage: test-dependencies
@@ -27,12 +26,15 @@ test-coveralls: test-dependencies
 	@mkdir -p build/logs
 	@XDEBUG_MODE=coverage $(PHPUNIT) --coverage-clover build/logs/clover.xml
 
-.PHONY: test-container-73
-test-container-73:
-	@docker-compose run --rm app73 sh
+.PHONY: test-container
+test-container: test-container-82
+
+.PHONY: test-container-82
+test-container-82:
+	@docker-compose run --rm app82 bash
 	@docker-compose down
 
-.PHONY: test-container-81
-test-container-81:
-	@docker-compose run --rm app81 sh
+.PHONY: test-container-83
+test-container-83:
+	@docker-compose run --rm app83 bash
 	@docker-compose down
diff --git a/README.md b/README.md
index d7b2b9f..0be1868 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,8 @@
 # DateTime
 
 [![Release](https://img.shields.io/packagist/v/ICanBoogie/DateTime.svg)](https://packagist.org/packages/icanboogie/datetime)
-[![Coverage Status](https://coveralls.io/repos/github/ICanBoogie/DateTime/badge.svg?branch=2.0)](https://coveralls.io/github/ICanBoogie/DateTime?branch=2.0)
-[![Packagist](https://img.shields.io/packagist/dm/icanboogie/datetime.svg)](https://packagist.org/packages/icanboogie/datetime)
+[![Code Coverage](https://coveralls.io/repos/github/ICanBoogie/DateTime/badge.svg?branch=3.0)](https://coveralls.io/github/ICanBoogie/DateTime?branch=3.0)
+[![Downloads](https://img.shields.io/packagist/dm/icanboogie/datetime.svg)](https://packagist.org/packages/icanboogie/datetime)
 
 This package extends the features of PHP [DateTime](http://www.php.net/manual/en/class.datetime.php)
 and [DateTimeZone](http://www.php.net/manual/en/class.datetimezone.php) classes to ease the
@@ -353,13 +353,20 @@ echo $date->localize('fr')->as_medium;        // 5 mai 2015 23:13:05
 
 The project is continuously tested by [GitHub actions](https://github.com/ICanBoogie/DateTime/actions).
 
-[![Tests](https://github.com/ICanBoogie/DateTime/actions/workflows/test.yml/badge.svg?branch=2.0)](https://github.com/ICanBoogie/DateTime/actions/workflows/test.yml)
+[![Tests](https://github.com/ICanBoogie/DateTime/actions/workflows/test.yml/badge.svg?branch=3.0)](https://github.com/ICanBoogie/DateTime/actions/workflows/test.yml)
+
+
+
+## Code of Conduct
+
+This project adheres to a [Contributor Code of Conduct](CODE_OF_CONDUCT.md). By participating in
+this project and its community, you're expected to uphold this code.
 
 
 
 ## Contributing
 
-Please see [CONTRIBUTING](CONTRIBUTING.md) for details.
+See [CONTRIBUTING](CONTRIBUTING.md) for details.
 
 
 
diff --git a/composer.json b/composer.json
index 5c19f46..798399e 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,11 @@
 	"name": "icanboogie/datetime",
 	"type": "library",
 	"description": "Extends the features of PHP DateTime and DateTimeZone",
-	"keywords": ["time", "date", "timezone"],
+	"keywords": [
+		"time",
+		"date",
+		"timezone"
+	],
 	"homepage": "https://icanboogie.org/",
 	"license": "BSD-3-Clause",
 	"authors": [
@@ -10,7 +14,7 @@
 			"name": "Olivier Laviale",
 			"email": "olivier.laviale@gmail.com",
 			"homepage": "https://olvlvl.com/",
-			"role" : "Developer"
+			"role": "Developer"
 		}
 	],
 	"support": {
@@ -21,11 +25,11 @@
 		"sort-packages": true
 	},
 	"require": {
-		"php": ">=7.3"
+		"php": ">=8.2"
 	},
 	"require-dev": {
 		"icanboogie/common": "^2.0",
-		"phpunit/phpunit": "^9.5"
+		"phpunit/phpunit": "^11.4"
 	},
 	"suggest": {
 		"icanboogie/common": "Allows finer exceptions to be thrown"
diff --git a/docker-compose.yaml b/docker-compose.yaml
index 953abf0..54dc2f5 100644
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -1,22 +1,21 @@
 ---
-version: "3.0"
 services:
-  app73:
+  app82:
     build:
       context: .
       args:
-        PHP_VERSION: 7.3
+        PHP_VERSION: "8.2"
     environment:
       PHP_IDE_CONFIG: "serverName=icanboogie-datetime"
     volumes:
       - .:/app:delegated
       - ~/.composer:/root/.composer:delegated
     working_dir: /app
-  app81:
+  app83:
     build:
       context: .
       args:
-        PHP_VERSION: 8.1
+        PHP_VERSION: "8.3"
     environment:
       PHP_IDE_CONFIG: "serverName=icanboogie-datetime"
     volumes:
diff --git a/lib/DateTime.php b/lib/DateTime.php
index f194158..0c52619 100644
--- a/lib/DateTime.php
+++ b/lib/DateTime.php
@@ -1,14 +1,5 @@
 <?php
 
-/*
- * This file is part of the ICanBoogie package.
- *
- * (c) Olivier Laviale <olivier.laviale@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
 namespace ICanBoogie;
 
 use DateTimeZone;
@@ -125,21 +116,21 @@
  * @property-read DateTime $saturday A new instance representing Saturday of the week. Time is reset to 00:00:00.
  * @property-read DateTime $sunday A new instance representing Sunday of the week. Time is reset to 00:00:00.
  *
- * @property-read string $as_atom The instance formatted according to {@link ATOM}.
- * @property-read string $as_cookie The instance formatted according to {@link COOKIE}.
- * @property-read string $as_iso8601 The instance formatted according to {@link ISO8601}.
- * @property-read string $as_rfc822 The instance formatted according to {@link RFC822}.
- * @property-read string $as_rfc850 The instance formatted according to {@link RFC850}.
- * @property-read string $as_rfc1036 The instance formatted according to {@link RFC1036}.
- * @property-read string $as_rfc1123 The instance formatted according to {@link RFC1123}.
- * @property-read string $as_rfc2822 The instance formatted according to {@link RFC2822}.
- * @property-read string $as_rfc3339 The instance formatted according to {@link RFC3339}.
- * @property-read string $as_rss The instance formatted according to {@link RSS}.
- * @property-read string $as_w3c The instance formatted according to {@link W3C}.
- * @property-read string $as_db The instance formatted according to {@link DB}.
- * @property-read string $as_number The instance formatted according to {@link NUMBER}.
- * @property-read string $as_date The instance formatted according to {@link DATE}.
- * @property-read string $as_time The instance formatted according to {@link TIME}.
+ * @property-read string $as_atom The instance formatted according to {@see ATOM}.
+ * @property-read string $as_cookie The instance formatted according to {@see COOKIE}.
+ * @property-read string $as_iso8601 The instance formatted according to {@see ISO8601}.
+ * @property-read string $as_rfc822 The instance formatted according to {@see RFC822}.
+ * @property-read string $as_rfc850 The instance formatted according to {@see RFC850}.
+ * @property-read string $as_rfc1036 The instance formatted according to {@see RFC1036}.
+ * @property-read string $as_rfc1123 The instance formatted according to {@see RFC1123}.
+ * @property-read string $as_rfc2822 The instance formatted according to {@see RFC2822}.
+ * @property-read string $as_rfc3339 The instance formatted according to {@see RFC3339}.
+ * @property-read string $as_rss The instance formatted according to {@see RSS}.
+ * @property-read string $as_w3c The instance formatted according to {@see W3C}.
+ * @property-read string $as_db The instance formatted according to {@see DB}.
+ * @property-read string $as_number The instance formatted according to {@see NUMBER}.
+ * @property-read string $as_date The instance formatted according to {@see DATE}.
+ * @property-read string $as_time The instance formatted according to {@see TIME}.
  *
  * @property TimeZone $zone The timezone of the instance.
  * @property-read DateTime $utc A new instance in the UTC timezone.
@@ -148,30 +139,30 @@
  * @property-read bool $is_local `true` if the instance is in the local timezone.
  * @property-read bool $is_dst `true` if time occurs during Daylight Saving Time in its time zone.
  *
- * @method string format_as_atom() format_as_atom() Formats the instance according to {@link ATOM}.
- * @method string format_as_cookie() format_as_cookie() Formats the instance according to {@link COOKIE}.
- * @method string format_as_iso8601() format_as_iso8601() Formats the instance according to {@link ISO8601}.
- * @method string format_as_rfc822() format_as_rfc822() Formats the instance according to {@link RFC822}.
- * @method string format_as_rfc850() format_as_rfc850() Formats the instance according to {@link RFC850}.
- * @method string format_as_rfc1036() format_as_rfc1036() Formats the instance according to {@link RFC1036}.
- * @method string format_as_rfc1123() format_as_rfc1123() Formats the instance according to {@link RFC1123}.
- * @method string format_as_rfc2822() format_as_rfc2822() Formats the instance according to {@link RFC2822}.
- * @method string format_as_rfc3339() format_as_rfc3339() Formats the instance according to {@link RFC3339}.
- * @method string format_as_rss() format_as_rss() Formats the instance according to {@link RSS}.
- * @method string format_as_w3c() format_as_w3c() Formats the instance according to {@link W3C}.
- * @method string format_as_db() format_as_db() Formats the instance according to {@link DB}.
- * @method string format_as_number() format_as_number() Formats the instance according to {@link NUMBER}.
- * @method string format_as_date() format_as_date() Formats the instance according to {@link DATE}.
- * @method string format_as_time() format_as_time() Formats the instance according to {@link TIME}.
+ * @method string format_as_atom() Formats the instance according to {@see ATOM}.
+ * @method string format_as_cookie() Formats the instance according to {@see COOKIE}.
+ * @method string format_as_iso8601() Formats the instance according to {@see ISO8601}.
+ * @method string format_as_rfc822() Formats the instance according to {@see RFC822}.
+ * @method string format_as_rfc850() Formats the instance according to {@see RFC850}.
+ * @method string format_as_rfc1036() Formats the instance according to {@see RFC1036}.
+ * @method string format_as_rfc1123() Formats the instance according to {@see RFC1123}.
+ * @method string format_as_rfc2822() Formats the instance according to {@see RFC2822}.
+ * @method string format_as_rfc3339() Formats the instance according to {@see RFC3339}.
+ * @method string format_as_rss() Formats the instance according to {@see RSS}.
+ * @method string format_as_w3c() Formats the instance according to {@see W3C}.
+ * @method string format_as_db() Formats the instance according to {@see DB}.
+ * @method string format_as_number() Formats the instance according to {@see NUMBER}.
+ * @method string format_as_date() Formats the instance according to {@see DATE}.
+ * @method string format_as_time() Formats the instance according to {@see TIME}.
  *
- * @see http://en.wikipedia.org/wiki/ISO_8601
+ * @link http://en.wikipedia.org/wiki/ISO_8601
  */
 class DateTime extends \DateTime implements \JsonSerializable
 {
 	/**
 	 * We redefine the constant to make sure that the cookie uses a valid pattern.
 	 *
-	 * @see http://grokbase.com/t/php/php-bugs/111xynxd6m/php-bug-bug-53879-new-datetime-createfromformat-fails-to-parse-cookie-expiration-date
+	 * @link http://grokbase.com/t/php/php-bugs/111xynxd6m/php-bug-bug-53879-new-datetime-createfromformat-fails-to-parse-cookie-expiration-date
 	 */
 	public const COOKIE = 'l, d-M-Y H:i:s T';
 
@@ -203,7 +194,7 @@ class DateTime extends \DateTime implements \JsonSerializable
 	static public $localizer = null;
 
 	/**
-	 * Creates a {@link DateTime} instance from a source.
+	 * Creates a {@see DateTime} instance from a source.
 	 *
 	 * <pre>
 	 * <?php
@@ -215,11 +206,17 @@ class DateTime extends \DateTime implements \JsonSerializable
 	 * DateTime::from('now');
 	 * </pre>
 	 *
-	 * @param mixed $source
-	 * @param mixed $timezone The time zone to use to create the time. The value is ignored if the
-	 * source is an instance of {@link \DateTime}.
+	 * @param self|\DateTime|string $source
+	 * @param DateTimeZone|string|null $timezone The time zone to use to create the time.
+	 * The value is ignored if the source is an instance of {@see \DateTime}.
+	 *
+	 * @throws \DateInvalidTimeZoneException
+	 * @throws \DateMalformedStringException
 	 */
-	static public function from($source, $timezone = null): self
+	static public function from(
+		self|\DateTime|string $source,
+		DateTimeZone|string|null $timezone = null
+	): static
 	{
 		if ($source instanceof static)
 		{
@@ -237,17 +234,22 @@ static public function from($source, $timezone = null): self
 	/**
 	 * Returns an instance with the current local time and the local time zone.
 	 *
-	 * **Note:** Subsequent calls return equal times, event if they are minutes apart. _now_
+	 * **Note:** Subsequent calls return equal times, event if they're minutes apart. _now_
 	 * actually refers to the `REQUEST_TIME` or, if it is now available, to the first time
 	 * the method was invoked.
+	 *
+	 * @throws \DateInvalidTimeZoneException
+	 * @throws \DateMalformedStringException
 	 */
-	static public function now(): self
+	static public function now(): static
 	{
 		static $now;
 
 		if (!$now)
 		{
-			$now = empty($_SERVER['REQUEST_TIME']) ? new static : (new static('@' . $_SERVER['REQUEST_TIME']))->local;
+			$now = empty($_SERVER['REQUEST_TIME'])
+				? new static()
+				: (new static('@' . $_SERVER['REQUEST_TIME']))->local;
 		}
 
 		return clone $now;
@@ -283,15 +285,16 @@ static public function right_now(): self
 	 * @param DateTimeZone|string $timezone The time zone in which the empty date is created.
 	 * Defaults to "UTC".
 	 *
-	 * @return DateTime
+	 * @throws \DateInvalidTimeZoneException
+	 * @throws \DateMalformedStringException
 	 */
-	static public function none($timezone = 'utc'): self
+	static public function none(DateTimeZone|string $timezone = 'utc'): static
 	{
 		return new static('0000-00-00', $timezone);
 	}
 
 	/**
-	 * If the time zone is specified as a string a {@link \DateTimeZone} instance is created and
+	 * If the time zone is specified as a string a {@see \DateTimeZone} instance is created and
 	 * used instead.
 	 *
 	 * <pre>
@@ -304,9 +307,10 @@ static public function none($timezone = 'utc'): self
 	 * new DateTime;
 	 * </pre>
 	 *
-	 * @param DateTimeZone|string|null $timezone
+	 * @throws \DateInvalidTimeZoneException
+	 * @throws \DateMalformedStringException
 	 */
-	public function __construct(string $time = 'now', $timezone = null)
+	public function __construct(string $time = 'now', DateTimeZone|string|null $timezone = null)
 	{
 		if (is_string($timezone))
 		{
@@ -316,12 +320,9 @@ public function __construct(string $time = 'now', $timezone = null)
 		parent::__construct($time, $timezone);
 	}
 
-	/**
-	 * @inheritdoc
-	 */
 	public function __get($property)
 	{
-		if (strpos($property, 'as_') === 0)
+		if (str_starts_with($property, 'as_'))
 		{
 			return $this->{ 'format_' . $property }();
 		}
@@ -435,6 +436,8 @@ public function __get($property)
 
 	/**
 	 * Returns Monday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_monday(): self
 	{
@@ -453,6 +456,8 @@ private function get_monday(): self
 
 	/**
 	 * Returns Tuesday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_tuesday(): self
 	{
@@ -461,6 +466,8 @@ private function get_tuesday(): self
 
 	/**
 	 * Returns Wednesday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_wednesday(): self
 	{
@@ -469,6 +476,8 @@ private function get_wednesday(): self
 
 	/**
 	 * Returns Thursday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_thursday(): self
 	{
@@ -477,6 +486,8 @@ private function get_thursday(): self
 
 	/**
 	 * Returns Friday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_friday(): self
 	{
@@ -485,6 +496,8 @@ private function get_friday(): self
 
 	/**
 	 * Returns Saturday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_saturday(): self
 	{
@@ -493,6 +506,8 @@ private function get_saturday(): self
 
 	/**
 	 * Returns Sunday of the week.
+	 *
+	 * @throws \DateMalformedStringException
 	 */
 	private function get_sunday(): self
 	{
@@ -509,22 +524,21 @@ private function get_sunday(): self
 		return $time;
 	}
 
+	private const READONLY_PROPERTIES = [
+		'quarter', 'week', 'year_day', 'weekday',
+		'tomorrow', 'yesterday', 'utc', 'local'
+	];
+
 	/**
-	 * Sets the {@link $year}, {@link $month}, {@link $day}, {@link $hour}, {@link $minute},
-	 * {@link $second}, {@link $timestamp} and {@link $zone} properties.
-	 *
-	 * @throws PropertyNotWritable in attempt to set a read-only property.
-	 * @throws PropertyNotDefined in attempt to set an unsupported property.
+	 * Sets the {@see $year}, {@see $month}, {@see $day}, {@see $hour}, {@see $minute},
+	 * {@see $second}, {@see $timestamp} and {@see $zone} properties.
 	 *
-	 * @inheritdoc
+	 * @throws PropertyNotWritable in an attempt to set a read-only property.
+	 * @throws PropertyNotDefined in an attempt to set an unsupported property.
+	 * @throws \DateInvalidTimeZoneException
 	 */
 	public function __set($property, $value): void
 	{
-		static $readonly = [
-			'quarter', 'week', 'year_day', 'weekday',
-			'tomorrow', 'yesterday', 'utc', 'local'
-		];
-
 		switch ($property)
 		{
 			case 'year':
@@ -545,7 +559,11 @@ public function __set($property, $value): void
 				return;
 		}
 
-		if (strpos($property, 'is_') === 0 || strpos($property, 'as_') === 0 || in_array($property, $readonly) || method_exists($this, 'get_' . $property))
+		if (str_starts_with($property, 'is_')
+			|| str_starts_with($property, 'as_')
+			|| in_array($property, self::READONLY_PROPERTIES)
+			|| method_exists($this, 'get_' . $property)
+		)
 		{
 			if (class_exists(PropertyNotWritable::class))
 			{
@@ -570,19 +588,17 @@ public function __set($property, $value): void
 	/**
 	 * Handles the `format_as_*` methods.
 	 *
-	 * If the format is {@link RFC822} or {@link RFC1123} and the time zone is equivalent to GMT,
+	 * If the format is {@see RFC822} or {@see RFC1123} and the time zone is equivalent to GMT,
 	 * the offset `+0000` is replaced by `GMT` according to the specs.
 	 *
-	 * If the format is {@link ISO8601} and the time zone is equivalent to UTC, the offset `+0000`
+	 * If the format is {@see ISO8601} and the time zone is equivalent to UTC, the offset `+0000`
 	 * is replaced by `Z` according to the specs.
 	 *
 	 * @throws \BadMethodCallException in attempt to call an unsupported method.
-	 *
-	 * @inheritdoc
 	 */
 	public function __call($method, $arguments)
 	{
-		if (strpos($method, 'format_as_') !== 0)
+		if (!str_starts_with($method, 'format_as_'))
 		{
 			throw new \BadMethodCallException("Unsupported method: $method.");
 		}
@@ -591,24 +607,18 @@ public function __call($method, $arguments)
 		$format = constant(__CLASS__ . '::' . $as);
 		$value = $this->format($format);
 
-		switch ($as)
+		return match ($as)
 		{
-			case 'RFC822':
-			case 'RFC1123':
-				return str_replace('+0000', 'GMT', $value);
-
-			case 'ISO8601':
-				return str_replace('+0000', 'Z', $value);
-
-			default:
-				return $value;
-		}
+			'RFC822', 'RFC1123' => str_replace('+0000', 'GMT', $value),
+			'ISO8601' => str_replace('+0000', 'Z', $value),
+			default => $value,
+		};
 	}
 
 	/**
-	 * Returns the datetime formatted as {@link ISO8601}.
+	 * Returns the datetime formatted as {@see ISO8601}.
 	 *
-	 * @return string The instance rendered as an {@link ISO8601} string, or an empty string if the
+	 * @return string The instance rendered as an {@see ISO8601} string, or an empty string if the
 	 * datetime is empty.
 	 */
 	public function __toString(): string
@@ -617,7 +627,7 @@ public function __toString(): string
 	}
 
 	/**
-	 * Returns a {@link ISO8601} representation of the instance.
+	 * Returns a {@see ISO8601} representation of the instance.
 	 */
 	public function jsonSerialize(): string
 	{
@@ -625,12 +635,14 @@ public function jsonSerialize(): string
 	}
 
 	/**
+	 * @inheritdoc
+	 *
 	 * The timezone can be specified as a string.
 	 *
-	 * If the timezone is `local` the timezone returned by {@link date_default_timezone_get()} is
+	 * If the timezone is `local` the timezone returned by {@see date_default_timezone_get()} is
 	 * used instead.
 	 *
-	 * @inheritdoc
+	 * @throws \DateInvalidTimeZoneException
 	 */
 	public function setTimezone($timezone): self
 	{
@@ -650,8 +662,8 @@ public function setTimezone($timezone): self
 	/**
 	 * Modifies the properties of the instance according to the options.
 	 *
-	 * The following properties can be updated: {@link $year}, {@link $month}, {@link $day},
-	 * {@link $hour}, {@link $minute} and {@link $second}.
+	 * The following properties can be updated: {@see $year}, {@see $month}, {@see $day},
+	 * {@see $hour}, {@see $minute} and {@see $second}.
 	 *
 	 * Note: Values exceeding ranges are added to their parent values.
 	 *
@@ -664,10 +676,13 @@ public function setTimezone($timezone): self
 	 * $time->change([ 'year' => 2000, 'second' => 0 ]);
 	 * </pre>
 	 *
-	 * @param array{ year: int, month: int, day: int, hour: int, minute: int, second: int, timezone: string } $options
+	 * @param array{ year: int, month: int, day: int, hour: int, minute: int, second: int,
+	 *     timezone: string } $options
 	 * @param bool $cascade If `true`, time options (`hour`, `minute`, `second`) reset
-	 * cascading, so if only the hour is passed, then minute and second is set to 0. If the hour
-	 * and minute is passed, then second is set to 0.
+	 * cascading, so if only the hour is passed, then minute and second are set to 0. If the hour
+	 * and minute are passed, the second is set to 0.
+	 *
+	 * @throws \DateInvalidTimeZoneException
 	 */
 	public function change(array $options, bool $cascade = false): self
 	{
@@ -739,10 +754,13 @@ public function change(array $options, bool $cascade = false): self
 	/**
 	 * Instantiate a new instance with changes properties.
 	 *
-	 * @param array{ year: int, month: int, day: int, hour: int, minute: int, second: int, timezone: string } $options
+	 * @param array{ year: int, month: int, day: int, hour: int, minute: int, second: int,
+	 *     timezone: string } $options
 	 * @param bool $cascade If `true`, time options (`hour`, `minute`, `second`) reset
-	 * cascading, so if only the hour is passed, then minute and second is set to 0. If the hour
-	 * and minute is passed, then second is set to 0.
+	 * cascading, so if only the hour is passed, then minute and second are set to 0. If the hour
+	 * and minute are passed, the second is set to 0.
+	 *
+	 * @throws \DateInvalidTimeZoneException
 	 */
 	public function with(array $options, bool $cascade = false): self
 	{
@@ -752,10 +770,10 @@ public function with(array $options, bool $cascade = false): self
 	}
 
 	/**
-	 * If the instance represents an empty date and the format is {@link DATE} or {@link DB},
+	 * If the instance represents an empty date and the format is {@see DATE} or {@see DB},
 	 * an empty date is returned, respectively "0000-00-00" and "0000-00-00 00:00:00". Note that
-	 * the time information is discarded for {@link DB}. This only apply to {@link DATE} and
-	 * {@link DB} formats. For instance {@link RSS} will return the following string:
+	 * the time information is discarded for {@see DB}. This only applies to {@see DATE} and
+	 * {@see DB} formats. For instance {@see RSS} will return the following string:
 	 * "Wed, 30 Nov -0001 00:00:00 +0000".
 	 *
 	 * @inheritdoc
@@ -775,7 +793,7 @@ public function format($format): string
 	 *
 	 * @return mixed
 	 *
-	 * @throws RuntimeException if {@link $localizer} is not defined.
+	 * @throws RuntimeException if {@see $localizer} is not defined.
 	 */
 	public function localize(string $locale = 'en')
 	{
diff --git a/lib/TimeZone.php b/lib/TimeZone.php
index 62a3877..20835b9 100644
--- a/lib/TimeZone.php
+++ b/lib/TimeZone.php
@@ -1,14 +1,5 @@
 <?php
 
-/*
- * This file is part of the ICanBoogie package.
- *
- * (c) Olivier Laviale <olivier.laviale@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
 namespace ICanBoogie;
 
 /**
@@ -33,8 +24,12 @@
  */
 class TimeZone extends \DateTimeZone
 {
-	static private $utc_time;
-	static private $cache;
+	static private \DateTime $utc_time;
+
+	/**
+	 * @var array<string, TimeZone>
+	 */
+	static private array $cache = [];
 
 	/**
 	 * Returns a timezone according to the specified source.
@@ -45,46 +40,42 @@ class TimeZone extends \DateTimeZone
 	 * the same instance.
 	 *
 	 * @param mixed $source Source of the timezone.
+	 *
+	 * @throws \DateInvalidTimeZoneException
 	 */
-	static public function from($source): self
+	static public function from(self|\DateTimeZone|\Stringable|string $source): self
 	{
 		if ($source instanceof self)
 		{
 			return $source;
 		}
-		else if ($source instanceof \DateTimeZone)
+
+		if ($source instanceof \DateTimeZone)
 		{
 			$source = $source->getName();
 		}
 
 		$source = (string) $source;
 
-		if (empty(self::$cache[$source]))
-		{
-			self::$cache[$source] = new static($source);
-		}
-
-		return self::$cache[$source];
+		return self::$cache[$source] ??= new self($source);
 	}
 
 	/**
 	 * The name of the timezone.
 	 *
 	 * Note: This variable is only used to provide information during debugging.
-	 *
-	 * @var string
 	 */
-	private $name;
+	private string $name;
 
 	/**
 	 * Location of the timezone.
-	 *
-	 * @var TimeZoneLocation
 	 */
-	private $location;
+	private TimeZoneLocation $location;
 
 	/**
-	 * Initializes the {@link $name} property.
+	 * Initializes the {@see $name} property.
+	 *
+	 * @throws \DateInvalidTimeZoneException
 	 */
 	public function __construct(string $timezone)
 	{
@@ -92,7 +83,7 @@ public function __construct(string $timezone)
 
 		$name = $this->getName();
 
-		if ($name == 'utc')
+		if ($name === 'utc')
 		{
 			$name = 'UTC';
 		}
@@ -101,11 +92,10 @@ public function __construct(string $timezone)
 	}
 
 	/**
-	 * Returns the {@link $location}, {@link $name} and {@link $offset} properties.
-	 *
-	 * @throws PropertyNotDefined in attempt to get an unsupported  property.
+	 * Returns the {@see $location}, {@see $name} and {@see $offset} properties.
 	 *
-	 * @inheritdoc
+	 * @throws PropertyNotDefined in an attempt to get an unsupported property.
+	 * @throws \DateMalformedStringException
 	 */
 	public function __get(string $property)
 	{
@@ -113,12 +103,7 @@ public function __get(string $property)
 		{
 			case 'location':
 
-				if (!$this->location)
-				{
-					$this->location = TimeZoneLocation::from($this);
-				}
-
-				return $this->location;
+				return $this->location ??= TimeZoneLocation::from($this);
 
 			case 'name':
 
@@ -126,12 +111,7 @@ public function __get(string $property)
 
 			case 'offset':
 
-				$utc_time = self::$utc_time;
-
-				if (!$utc_time)
-				{
-					self::$utc_time = $utc_time = new \DateTime('now', new \DateTimeZone('utc'));
-				}
+				$utc_time = self::$utc_time ??= new \DateTime('now', new \DateTimeZone('utc'));
 
 				return $this->getOffset($utc_time);
 		}
diff --git a/phpunit.xml b/phpunit.xml
index 7b5140a..9d19d39 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -1,15 +1,24 @@
 <?xml version="1.0"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-		 xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.5/phpunit.xsd" colors="true"
-		 bootstrap="./vendor/autoload.php">
-	<coverage>
-		<include>
-			<directory suffix=".php">./lib</directory>
-		</include>
-	</coverage>
+		 xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.4/phpunit.xsd"
+		 beStrictAboutCoverageMetadata="true"
+		 beStrictAboutOutputDuringTests="true"
+		 bootstrap="./vendor/autoload.php"
+		 colors="true"
+		 displayDetailsOnTestsThatTriggerDeprecations="true"
+		 displayDetailsOnTestsThatTriggerNotices="true"
+		 displayDetailsOnTestsThatTriggerWarnings="true"
+		 displayDetailsOnPhpunitDeprecations="true"
+		 executionOrder="depends,defects"
+>
 	<testsuites>
-		<testsuite name="ICanBoogie/DateTime">
+		<testsuite name="icanboogie/datetime">
 			<directory>./tests</directory>
 		</testsuite>
 	</testsuites>
+    <source>
+        <include>
+            <directory>lib</directory>
+        </include>
+    </source>
 </phpunit>
diff --git a/tests/DateTimeTest.php b/tests/DateTimeTest.php
index 7b13ae9..cb86a10 100644
--- a/tests/DateTimeTest.php
+++ b/tests/DateTimeTest.php
@@ -1,19 +1,11 @@
 <?php
 
-/*
- * This file is part of the ICanBoogie package.
- *
- * (c) Olivier Laviale <olivier.laviale@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
 namespace Test\ICanBoogie;
 
 use ICanBoogie\DateTime;
 use ICanBoogie\PropertyNotDefined;
 use ICanBoogie\PropertyNotWritable;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Test\ICanBoogie\DateTimeTest\MyDateTime;
 use function array_map;
@@ -27,9 +19,7 @@ protected function setUp(): void
 		date_default_timezone_set('Europe/Paris');
 	}
 
-	/**
-	 * @dataProvider provide_readonly
-	 */
+	#[DataProvider("provide_readonly")]
 	public function test_readonly(string $property): void
 	{
 		$d = DateTime::now();
@@ -39,13 +29,13 @@ public function test_readonly(string $property): void
 		$d->{ $property } = null;
 	}
 
-	public function provide_readonly(): array
+	public static function provide_readonly(): array
 	{
 		$properties = <<<EOT
-		quarter week weekday year_day 
+		quarter week weekday year_day
 		is_monday is_tuesday is_wednesday is_thursday is_friday is_saturday is_sunday
-		is_today is_past is_future is_empty 
-		tomorrow yesterday 
+		is_today is_past is_future is_empty
+		tomorrow yesterday
 		monday tuesday wednesday thursday friday saturday sunday
 		utc is_utc
 		local is_local
@@ -170,7 +160,7 @@ public function test_change()
 		$this->assertEquals('2001-01-01 01:01:01', $d->as_db);
 	}
 
-	public function provider_test_change_cascade(): array
+	public static function provide_test_change_cascade(): array
 	{
 		return [
 			['2001-01-01 01:02:00', [ 'minute' => 2 ]],
@@ -198,9 +188,7 @@ public function test_change_on_timezone_option(): void
 		$this->assertSame($expectedTimezone, $resultTimezone->getName());
 	}
 
-	/**
-	 * @dataProvider provider_test_change_cascade
-	 */
+	#[DataProvider('provide_test_change_cascade')]
 	public function test_change_cascade($expected_datetime, $change_format): void
 	{
 		$datetime = '2001-01-01 01:01:01';
@@ -221,7 +209,7 @@ public function test_with(): void
 		$this->assertEquals('2015-05-05 01:01:01', $e->as_db);
 	}
 
-	public function provider_test_get_year(): array
+	public static function provide_test_get_year(): array
 	{
 		return [
 			['2012-12-16 15:00:00', 2012],
@@ -230,9 +218,7 @@ public function provider_test_get_year(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_year
-	 */
+	#[DataProvider('provide_test_get_year')]
 	public function test_get_year($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
@@ -246,7 +232,7 @@ public function test_set_year(): void
 		$this->assertEquals('2009-01-01 01:01:01', $d->as_db);
 	}
 
-	public function provider_test_get_quarter(): array
+	public static function provide_test_get_quarter(): array
 	{
 		return [
 			['2012-01-16 15:00:00', 1],
@@ -264,16 +250,14 @@ public function provider_test_get_quarter(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_quarter
-	 */
+	#[DataProvider('provide_test_get_quarter')]
 	public function test_get_quarter($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
 		$this->assertEquals($expected, $d->quarter);
 	}
 
-	public function provider_test_get_month(): array
+	public static function provide_test_get_month(): array
 	{
 		return [
 			['2012-01-16 15:00:00', 1],
@@ -282,9 +266,7 @@ public function provider_test_get_month(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_month
-	 */
+	#[DataProvider('provide_test_get_month')]
 	public function test_get_month($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
@@ -298,7 +280,7 @@ public function test_set_month(): void
 		$this->assertEquals('2001-09-01 01:01:01', $d->as_db);
 	}
 
-	public function provider_test_get_week(): array
+	public static function provide_test_get_week(): array
 	{
 		return [
 			['2012-01-01 15:00:00', 52],
@@ -306,16 +288,14 @@ public function provider_test_get_week(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_week
-	 */
+	#[DataProvider('provide_test_get_week')]
 	public function test_get_week($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
 		$this->assertEquals($expected, $d->week);
 	}
 
-	public function provider_test_get_year_day(): array
+	public static function provide_test_get_year_day(): array
 	{
 		return [
 			['2012-01-01 15:00:00', 1],
@@ -323,16 +303,14 @@ public function provider_test_get_year_day(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_year_day
-	 */
+	#[DataProvider('provide_test_get_year_day')]
 	public function test_get_year_day($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
 		$this->assertEquals($expected, $d->year_day);
 	}
 
-	public function provider_test_get_weekday(): array
+	public static function provide_test_get_weekday(): array
 	{
 		return [
 			['2012-12-17 15:00:00', 1],
@@ -347,15 +325,15 @@ public function provider_test_get_weekday(): array
 
 	/**
 	 * Sunday must be 7, Monday must be 1.
-	 * @dataProvider provider_test_get_weekday
 	 */
+	#[DataProvider('provide_test_get_weekday')]
 	public function test_get_weekday($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
 		$this->assertEquals($expected, $d->weekday);
 	}
 
-	public function provider_test_get_day(): array
+	public static function provide_test_get_day(): array
 	{
 		return [
 			['2012-12-16 15:00:00', 16],
@@ -364,9 +342,7 @@ public function provider_test_get_day(): array
 		];
 	}
 
-	/**
-	 * @dataProvider provider_test_get_day
-	 */
+	#[DataProvider('provide_test_get_day')]
 	public function test_get_day($datetime, $expected): void
 	{
 		$d = new DateTime($datetime);
@@ -558,16 +534,14 @@ public function test_get_yesterday()
 		$this->assertEquals('2013-02-09 00:00:00', $d->yesterday->as_db);
 	}
 
-	/**
-	 * @dataProvider provide_test_day_instance
-	 */
+	#[DataProvider('provide_test_day_instance')]
 	public function test_day_instance($date, $expected, $day): void
 	{
 		$d = new DateTime($date);
 		$this->assertEquals($expected, $d->$day->as_db);
 	}
 
-	public function provide_test_day_instance(): array
+	public static function provide_test_day_instance(): array
 	{
 		return [
 
diff --git a/tests/TimeZoneLocationTest.php b/tests/TimeZoneLocationTest.php
index d5ad980..ee3c33e 100644
--- a/tests/TimeZoneLocationTest.php
+++ b/tests/TimeZoneLocationTest.php
@@ -1,14 +1,5 @@
 <?php
 
-/*
- * This file is part of the ICanBoogie package.
- *
- * (c) Olivier Laviale <olivier.laviale@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
 namespace Test\ICanBoogie;
 
 use DateTimeZone;
@@ -16,6 +7,7 @@
 use ICanBoogie\PropertyNotDefined;
 use ICanBoogie\PropertyNotWritable;
 use ICanBoogie\TimeZoneLocation;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use function array_map;
 use function preg_split;
@@ -24,9 +16,7 @@
 class TimeZoneLocationTest extends TestCase
 {
 
-	/**
-	 * @dataProvider provide_readonly
-	 */
+	#[DataProvider('provide_readonly')]
 	public function test_readonly(string $property): void
 	{
 		$zone = new DateTimeZone('Europe/Paris');
@@ -38,7 +28,7 @@ public function test_readonly(string $property): void
 		$instance->$property = null;
 	}
 
-	public function provide_readonly(): array
+	public static function provide_readonly(): array
 	{
 		$properties = <<<EOT
 		country_code