diff --git a/.editorconfig b/.editorconfig
index c451dda..7d38cf2 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -14,5 +14,5 @@ trim_trailing_whitespace = true
 [*.md]
 trim_trailing_whitespace = false
 
-[*.yml]
+[*.{yml,yaml}]
 indent_size = 2
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..cdac80f
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,11 @@
+# Reduce Composer package download by removing obsolete files
+
+/.editorconfig      export-ignore
+/.gitattributes     export-ignore
+/.github            export-ignore
+/.gitignore         export-ignore
+/.php_cs.dist.php   export-ignore
+/CODE_OF_CONDUCT.md export-ignore
+/CONTRIBUTING.md    export-ignore
+/phpunit.xml.dist   export-ignore
+/tests              export-ignore
diff --git a/.github/ISSUE_TEMPLATE/BUG_REPORT.md b/.github/ISSUE_TEMPLATE/BUG_REPORT.md
new file mode 100644
index 0000000..48f1395
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/BUG_REPORT.md
@@ -0,0 +1,19 @@
+---
+name: Bug report
+about: Create a report to help us improve this project
+title: ''
+labels: bug
+assignees: sebastiaanluca
+---
+
+### Description
+
+### Expected result
+
+### Steps to reproduce
+
+Please provide a fully working repository that reproduces the bug.
+
+### Additional info
+
+Logs, error output, setup, environment, packages, versions, etc.
diff --git a/.github/ISSUE_TEMPLATE/FEATURE_REQUEST.md b/.github/ISSUE_TEMPLATE/FEATURE_REQUEST.md
new file mode 100644
index 0000000..60093d4
--- /dev/null
+++ b/.github/ISSUE_TEMPLATE/FEATURE_REQUEST.md
@@ -0,0 +1,23 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: feature
+assignees: sebastiaanluca
+---
+
+### Description
+
+A clear and concise description of the problem or proposal.
+
+### Suggested solution
+
+A clear and concise description of what you want to happen.
+
+### Possible alternatives
+
+A clear and concise description of any alternative solutions or features you've considered.
+
+### Additional context
+
+Any other context or screenshots to help situate and understand the requested feature.
diff --git a/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
similarity index 73%
rename from PULL_REQUEST_TEMPLATE.md
rename to .github/PULL_REQUEST_TEMPLATE.md
index 7ff85fa..8828020 100644
--- a/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -1,3 +1,11 @@
+---
+name: Pull request
+about: Create a new pull request to merge code into the main branch
+title: 'A short, descriptive title'
+labels: ''
+assignees: sebastiaanluca
+---
+
 ## PR Type
 
 What kind of pull request is this? Put an `x` in all the boxes that apply:
@@ -8,17 +16,16 @@ What kind of pull request is this? Put an `x` in all the boxes that apply:
 - [ ] Change feature (non-breaking change which either changes or refactors existing functionality)
 - [ ] Breaking change (fix or feature that would cause existing functionality to change)
 
-## What does it change?
-
-Describe your changes in detail.
+---
 
-## Why this PR?
+### Description
 
-Why is this change required? What problem does it solve?
+Clearly describe what this pull request changes and why.
 
-## How has this been tested?
+### Steps to follow to verify functionality
 
-Please describe in detail how you tested your changes (or are planning on testing them).
+1. Clearly state which actions should be performed to fully and correctly review this issue.
+2. …
 
 ## Checklist
 
@@ -32,3 +39,4 @@ To facilitate merging your change and the approval of this PR, please make sure
 - If the change to the code requires a change to the documentation, it has been updated accordingly
 
 If you're unsure about any of these, don't hesitate to ask. We're here to help!
+
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 0000000..dfd061a
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,54 @@
+name: Check code
+
+on:
+  push:
+  pull_request:
+
+jobs:
+
+  check:
+    name: Run PHP tests - PHP ${{ matrix.php }} - ${{ matrix.dependency-version }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        php: [8.0, 8.1]
+        dependency-version: [prefer-lowest, prefer-stable]
+        os: [ubuntu-latest]
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v2
+
+      - name: Cache PHP dependencies
+        uses: actions/cache@v2
+        with:
+          path: '**/vendor'
+          key: ${{ runner.os }}-vendor-cache-${{ hashFiles('**/composer.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-vendor-cache-
+
+      - name: Cache Composer dependencies
+        uses: actions/cache@v2
+        with:
+          path: ~/.composer/cache/files
+          key: composer-${{ runner.os }}-php-${{ matrix.php }}-${{ hashFiles('composer.json') }}
+
+      - name: Validate Composer configuration file
+        run: composer validate --strict
+
+      - name: Set up PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: mbstring
+          coverage: none
+
+      - name: Install dependencies
+        run: composer update --${{ matrix.dependency-version }} --prefer-dist --no-interaction --no-progress --optimize-autoloader
+
+      - name: Lint code
+        run: vendor/bin/php-cs-fixer fix --dry-run --diff
+
+      - name: Run tests
+        run: vendor/bin/phpunit
diff --git a/.gitignore b/.gitignore
index 5826402..28188ad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,7 @@
-/vendor
-composer.phar
+.idea
+.php-cs-fixer.cache
+.phpunit.result.cache
 composer.lock
-.DS_Store
+composer.phar
+phpunit.xml
+vendor/
diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
new file mode 100644
index 0000000..8db5cb0
--- /dev/null
+++ b/.php-cs-fixer.dist.php
@@ -0,0 +1,242 @@
+<?php
+
+// Last reviewed: v2.19 (Testament)
+// Based on https://gist.github.com/laravel-shift/cab527923ed2a109dda047b97d53c200
+
+use PhpCsFixer\Config;
+use PhpCsFixer\Finder;
+
+$rules = [
+    '@PSR1' => true,
+    '@PSR2' => true,
+    '@PhpCsFixer' => true,
+    '@Symfony' => true,
+    '@PHP70Migration' => true,
+    '@PHP70Migration:risky' => true,
+    '@PHP71Migration' => true,
+    '@PHP71Migration:risky' => true,
+    '@PHP73Migration' => true,
+    '@PHPUnit75Migration:risky' => true,
+    'final_class' => false,
+    'new_with_braces' => false,
+    'strict_comparison' => true,
+    'list_syntax' => ['syntax' => 'short'],
+    'mb_str_functions' => true,
+    'class_attributes_separation' => [
+        'elements' => [
+            'method' => 'one',
+        ],
+    ],
+    'no_extra_blank_lines' => [
+        'tokens' => [
+            'break',
+            'continue',
+            'curly_brace_block',
+            'extra',
+            'parenthesis_brace_block',
+            'return',
+            'square_brace_block',
+            'throw',
+            'use',
+            'use_trait',
+            'switch',
+
+            'case',
+            'default',
+        ],
+    ],
+    'no_blank_lines_before_namespace' => false,
+    'nullable_type_declaration_for_default_null_value' => true,
+    'increment_style' => ['style' => 'pre'],
+    'self_static_accessor' => true,
+    'static_lambda' => false,
+    'no_empty_phpdoc' => true,
+    'no_superfluous_phpdoc_tags' => [
+        'remove_inheritdoc' => true,
+    ],
+    'phpdoc_line_span' => [
+        'const' => 'multi',
+        'method' => 'multi',
+        'property' => 'multi',
+    ],
+    'general_phpdoc_tag_rename' => true,
+    'phpdoc_add_missing_param_annotation' => ['only_untyped' => true],
+    'phpdoc_align' => ['align' => 'left'],
+    'phpdoc_indent' => true,
+    'phpdoc_inline_tag_normalizer' => true,
+    'phpdoc_no_access' => true,
+    'phpdoc_no_empty_return' => false,
+    'phpdoc_no_package' => true,
+    'phpdoc_no_useless_inheritdoc' => true,
+    'phpdoc_order' => true,
+    'phpdoc_order_by_value' => false,
+    'phpdoc_scalar' => true,
+    'phpdoc_single_line_var_spacing' => true,
+    'phpdoc_summary' => true,
+    'phpdoc_tag_casing' => ['tags' => ['inheritDoc']],
+    'phpdoc_tag_type' => true,
+    'phpdoc_to_comment' => true,
+    'phpdoc_trim' => true,
+    'phpdoc_types' => ['groups' => ['simple', 'alias']],
+    'phpdoc_types_order' => ['null_adjustment' => 'always_last'],
+    'phpdoc_var_annotation_correct_order' => true,
+    'phpdoc_var_without_name' => true,
+    'align_multiline_comment' => ['comment_type' => 'phpdocs_like'],
+    'php_unit_test_class_requires_covers' => false,
+    'php_unit_internal_class' => false,
+    'yoda_style' => false,
+    'ordered_class_elements' => [
+        'order' => [
+            'use_trait',
+            'constant_public',
+            'constant_protected',
+            'constant_private',
+
+            'property_static',
+            'property_public_static',
+            'property_protected_static',
+            'property_private_static',
+
+            'property',
+            'property_public',
+            'property_protected',
+            'property_private',
+
+            'construct',
+            'destruct',
+            'magic',
+
+            'method_static',
+            'method_public_abstract_static',
+            'method_public_static',
+            'method_protected_abstract_static',
+            'method_protected_static',
+            'method_private_static',
+            'method_public_abstract',
+            'method_public',
+            'method_protected_abstract',
+            'method_protected',
+            'method_private',
+        ],
+    ],
+    'array_syntax' => ['syntax' => 'short'],
+    'blank_line_after_namespace' => true,
+    'blank_line_after_opening_tag' => true,
+    'braces' => true,
+    'cast_spaces' => true,
+    'concat_space' => [
+        'spacing' => 'none',
+    ],
+    'declare_equal_normalize' => true,
+    'elseif' => true,
+    'encoding' => true,
+    'full_opening_tag' => true,
+    'fully_qualified_strict_types' => true, // added by Shift
+    'function_declaration' => true,
+    'function_typehint_space' => true,
+    'heredoc_to_nowdoc' => true,
+    'include' => true,
+    'indentation_type' => true,
+    'linebreak_after_opening_tag' => true,
+    'line_ending' => true,
+    'lowercase_cast' => true,
+    'lowercase_keywords' => true,
+    'lowercase_static_reference' => true, // added from Symfony
+    'magic_method_casing' => true, // added from Symfony
+    'magic_constant_casing' => true,
+    'method_argument_space' => true,
+    'native_function_casing' => true,
+    'no_alias_functions' => false,
+    'no_blank_lines_after_class_opening' => true,
+    'no_blank_lines_after_phpdoc' => true,
+    'no_closing_tag' => true,
+    'no_empty_statement' => true,
+    'no_leading_import_slash' => true,
+    'no_leading_namespace_whitespace' => true,
+    'no_mixed_echo_print' => [
+        'use' => 'echo',
+    ],
+    'no_multiline_whitespace_around_double_arrow' => true,
+    'multiline_whitespace_before_semicolons' => [
+        'strategy' => 'no_multi_line',
+    ],
+    'no_short_bool_cast' => true,
+    'no_singleline_whitespace_before_semicolons' => true,
+    'no_spaces_after_function_name' => true,
+    'no_spaces_inside_parenthesis' => true,
+    'no_trailing_comma_in_list_call' => false,
+    'no_trailing_comma_in_singleline_array' => true,
+    'no_trailing_whitespace' => true,
+    'no_trailing_whitespace_in_comment' => true,
+    'no_unreachable_default_argument_value' => true,
+    'no_useless_return' => true,
+    'no_whitespace_before_comma_in_array' => true,
+    'no_whitespace_in_blank_line' => true,
+    'normalize_index_brace' => true,
+    'not_operator_with_successor_space' => true,
+    'object_operator_without_whitespace' => true,
+    'self_accessor' => false,
+    'short_scalar_cast' => true,
+    'simplified_null_return' => false, // disabled by Shift
+    'single_blank_line_at_eof' => true,
+    'single_blank_line_before_namespace' => true,
+    'single_import_per_statement' => true,
+    'single_line_after_imports' => true,
+    'single_line_comment_style' => [
+        'comment_types' => ['hash'],
+    ],
+    'single_quote' => true,
+    'space_after_semicolon' => true,
+    'standardize_not_equals' => true,
+    'switch_case_semicolon_to_colon' => true,
+    'switch_case_space' => true,
+    'ternary_operator_spaces' => true,
+    'trim_array_spaces' => true,
+    'unary_operator_spaces' => true,
+    'whitespace_after_comma_in_array' => true,
+    'constant_case' => ['case' => 'lower'],
+    'psr_autoloading' => true,
+    'trailing_comma_in_multiline' => ['elements' => ['arrays']],
+    'binary_operator_spaces' => [
+        'default' => 'single_space',
+    ],
+    'types_spaces' => [
+        'space' => 'none',
+    ],
+    'blank_line_before_statement' => [
+        'statements' => ['return'],
+    ],
+    'class_definition' => [
+        'multi_line_extends_each_single_line' => true,
+        'single_item_single_line' => true,
+        'single_line' => true,
+    ],
+    'ordered_imports' => [
+        'sort_algorithm' => 'alpha',
+    ],
+    'no_unneeded_control_parentheses' => [
+        'statements' => ['break', 'clone', 'continue', 'echo_print', 'return', 'switch_case', 'yield'],
+    ],
+    'no_spaces_around_offset' => [
+        'positions' => ['inside', 'outside'],
+    ],
+    'visibility_required' => [
+        'elements' => ['property', 'method', 'const'],
+    ],
+];
+
+$finder = Finder::create()
+    ->in([
+        __DIR__.'/src',
+        __DIR__.'/tests',
+    ])
+    ->name('*.php')
+    ->notName('*.blade.php')
+    ->ignoreDotFiles(true)
+    ->ignoreVCS(true);
+
+return (new Config)
+    ->setRules($rules)
+    ->setFinder($finder)
+    ->setRiskyAllowed(true)
+    ->setUsingCache(true);
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 2b69546..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,44 +0,0 @@
-language: php
-
-php:
-  - 7.3
-  - 7.4
-  - nightly
-
-cache:
-  directories:
-    - $HOME/.composer/cache
-
-env:
-  matrix:
-    - LARAVEL_VERSION="^7.0" COMPOSER_FLAGS="--prefer-lowest"
-    - LARAVEL_VERSION="^7.0" COMPOSER_FLAGS="--prefer-stable"
-    - LARAVEL_VERSION="^8.0" COMPOSER_FLAGS="--prefer-lowest"
-    - LARAVEL_VERSION="^8.0" COMPOSER_FLAGS="--prefer-stable"
-    - LARAVEL_VERSION="dev-master" ORCHESTRA_VERSION="dev-master" COMPOSER_FLAGS="--prefer-lowest" MINIMUM_STABILITY="dev"
-    - LARAVEL_VERSION="dev-master" ORCHESTRA_VERSION="dev-master" COMPOSER_FLAGS="--prefer-stable" MINIMUM_STABILITY="dev"
-
-matrix:
-  allow_failures:
-    - php: nightly
-    - env: LARAVEL_VERSION="dev-master" ORCHESTRA_VERSION="dev-master" COMPOSER_FLAGS="--prefer-lowest" MINIMUM_STABILITY="dev"
-    - env: LARAVEL_VERSION="dev-master" ORCHESTRA_VERSION="dev-master" COMPOSER_FLAGS="--prefer-stable" MINIMUM_STABILITY="dev"
-  fast_finish: true
-
-before_install:
-  - composer validate --strict
-  - travis_retry composer self-update
-  - if [[ -n ${MINIMUM_STABILITY} ]]; then composer config minimum-stability ${MINIMUM_STABILITY}; echo "Minimum stability set to ${MINIMUM_STABILITY}"; else echo "Minimum stability left unchanged"; fi
-  - if [[ -n ${ORCHESTRA_VERSION} ]]; then composer require orchestra/testbench=${ORCHESTRA_VERSION} --dev --no-update; else echo "orchestra/testbench version requirement left unchanged"; fi
-  - composer require laravel/framework=${LARAVEL_VERSION} --no-update
-
-install:
-  - travis_retry composer update ${COMPOSER_FLAGS} --no-interaction --prefer-dist
-
-script:
-  - vendor/bin/phpunit
-
-notifications:
-  email:
-    on_failure: change
-    on_success: never
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 122aeee..601908d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,27 @@ All Notable changes to `sebastiaanluca/laravel-boolean-dates` will be documented
 
 Updates should follow the [Keep a CHANGELOG](http://keepachangelog.com/) principles.
 
+## 6.0.0 (2022-03-13)
+
+⚠️ This release is a complete rewrite and changes the way it has to be used. Please consult the [README](README.md) for instructions.
+
+### Added
+
+- Added support for Laravel 9
+
+### Changed
+
+- Switched to using `\Illuminate\Support\Carbon` and `\Carbon\CarbonImmutable` instead of `\Carbon\Carbon`
+- Cleaned up code internally
+- Added `BooleanDateAttribute`
+
+### Removed
+
+- Dropped support for PHP 7.x
+- Dropped support for Laravel 7 and 8
+- Removed requirements for `nesbot/carbon`
+- Removed `HasBooleanDates` trait
+
 ## 5.0.0 (2020-10-19)
 
 ### Added
diff --git a/ISSUE_TEMPLATE.md b/ISSUE_TEMPLATE.md
deleted file mode 100644
index 08bee51..0000000
--- a/ISSUE_TEMPLATE.md
+++ /dev/null
@@ -1,24 +0,0 @@
-## Description
-
-Make it clear if the issue is a **bug**, an **enhancement** or just a **question**. The easiest way to indicate this is to prefix the title, e.g. `[Question] I have a question`.
-
-Provide a detailed description of the change or addition you are proposing. Include some screenshots or code examples if possible.
-
-### Your environment
-
-If you're reporting a bug or asking a specific question, include as many relevant details about your environment so we can reproduce it. The more, the better.
-
-- Package version or last commit
-- Operating system and version
-- PHP version
-- Laravel version
-- Related package versions
-- …
-
-## Context
-
-Why is this change important to you? How would you use it? How can it benefit other users?
-
-## Possible implementation
-
-Not obligatory, but suggest an idea for implementing addition or change.
diff --git a/README.md b/README.md
index 12eb9bd..31d7463 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# Automatically convert Eloquent model boolean attributes to dates (and back)
+# Convert Eloquent boolean attributes to dates (and back)
 
 [![Latest stable release][version-badge]][link-packagist]
 [![Software license][license-badge]](LICENSE.md)
@@ -11,7 +11,7 @@
 [![Follow @sebastiaanluca on Twitter][twitter-profile-badge]][link-twitter]
 [![Share this package on Twitter][twitter-share-badge]][link-twitter-share]
 
-**A package to automatically convert boolean fields to dates (and back to booleans) so you always know when something was accepted or changed.**
+**Automatically convert Eloquent model boolean fields to dates (and back to booleans)** so you always know _when_ something was accepted or changed.
 
 Say you've got a registration page for users where they need to accept your terms and perhaps can opt-in to certain features using checkboxes. With the new(-ish) GDPR privacy laws, you're somewhat required to not just keep track of the fact *if* they accepted those (or not), but also *when* they did.
 
@@ -23,26 +23,19 @@ User registration controller:
 $input = request()->input();
 
 $user = User::create([
-    'has_accepted_terms_and_conditions' => $input['terms'],
-    'allows_data_processing' => $input['data_processing'],
-    'has_agreed_to_something' => $input['something'],
+    'has_accepted_terms' => $input['terms'],
+    'is_subscribed_to_newsletter' => $input['newsletter'],
 ]);
 ```
 
 Anywhere else in your code:
 
 ```php
-$user->has_accepted_terms_and_conditions;
+// true or false (boolean)
+$user->has_accepted_terms;
 
-/*
- * true or false (boolean)
- */
- 
-$user->accepted_terms_and_conditions_at;
-
-/*
- * 2018-05-10 16:24:22 (Carbon instance)
- */
+// 2018-05-10 16:24:22 (Carbon instance)
+$user->accepted_terms_at;
 ```
 
 ## Table of contents
@@ -66,8 +59,8 @@ $user->accepted_terms_and_conditions_at;
 
 ## Requirements
 
-- PHP 7.3 or higher
-- Laravel 7.0 or higher
+- PHP 8 or 8.1
+- Laravel ^9.2
 
 ## How to install
 
@@ -77,81 +70,118 @@ $user->accepted_terms_and_conditions_at;
 composer require sebastiaanluca/laravel-boolean-dates
 ```
 
-**Require the `HasBooleanDates` trait** in your Eloquent model, then add the `$booleanDates` field:
+**Set up your Eloquent model** by:
+
+1. Adding your datetime columns to `$casts`
+2. Adding the boolean attributes to `$appends`
+3. Creating attribute accessors and mutators for each field
 
 ```php
 <?php
 
+declare(strict_types=1);
+
 use Illuminate\Database\Eloquent\Model;
-use SebastiaanLuca\BooleanDates\HasBooleanDates;
+use SebastiaanLuca\BooleanDates\BooleanDateAttribute;
 
 class User extends Model
 {
-    use HasBooleanDates;
-    
     /**
-     * @var array
+     * The attributes that should be cast to native types.
+     *
+     * @var array<string, string>
+     */
+    protected $casts = [
+        'accepted_terms_at' => 'immutable_datetime',
+        'subscribed_to_newsletter_at' => 'datetime',
+    ];
+
+    /**
+     * The accessors to append to the model's array form.
+     *
+     * @var array<int, string>
      */
-    protected $booleanDates = [
-        'has_accepted_terms_and_conditions' => 'accepted_terms_at',
-        'allows_data_processing' => 'accepted_processing_at',
-        'has_agreed_to_something' => 'agreed_to_something_at',
+    protected $appends = [
+        'has_accepted_terms',
+        'is_subscribed_to_newsletter',
     ];
+
+    protected function hasAcceptedTerms(): Attribute
+    {
+        return BooleanDateAttribute::for('accepted_terms_at');
+    }
+
+    protected function isSubscribedToNewsletter(): Attribute
+    {
+        return BooleanDateAttribute::for('subscribed_to_newsletter_at');
+    }
 }
 ```
 
-To wrap up, create a **migration** to create a new or alter your existing table and add the timestamp fields:
+Optionally, if your database table hasn't got the datetime columns yet, create a **migration** to create a new table or alter your existing table to add the timestamp fields:
 
 ```php
 <?php
 
+declare(strict_types=1);
+
 use Illuminate\Database\Migrations\Migration;
 use Illuminate\Database\Schema\Blueprint;
 use Illuminate\Support\Facades\Schema;
 
-class AddAgreementFields extends Migration
-{
-    /**
-     * Run the migrations.
-     *
-     * @return void
-     */
-    public function up() : void
+return new class extends Migration {
+    public function up(): void
     {
-        Schema::table('users', function (Blueprint $table) {
+        Schema::table('users', static function (Blueprint $table): void {
             $table->timestamp('accepted_terms_at')->nullable();
-            $table->timestamp('accepted_processing_at')->nullable();
-            $table->timestamp('agreed_to_something_at')->nullable();
+            $table->timestamp('subscribed_to_newsletter_at')->nullable();
         });
     }
-}
-```
+};
 
-Note: the related boolean fields are dynamic and do not need database fields.
+```
 
 ## How to use
 
 ### Saving dates
 
-If a boolean date field's value is true, it'll be automatically converted to the current datetime:
+If a boolean date field's value is true-ish, it'll be automatically converted to the current datetime. You can use anything like booleans, strings, positive integers, and so on.
 
 ```php
 $user = new User;
 
 // Setting values explicitly
-$user->has_accepted_terms_and_conditions = true;
-$user->allows_data_processing = 'yes';
+$user->has_accepted_terms = true;
+$user->has_accepted_terms = 'yes';
+$user->has_accepted_terms = '1';
+$user->has_accepted_terms = 1;
 
 // Or using attribute filling
-$user->fill([
-   'has_agreed_to_something' => 1, 
-]);
+$user->fill(['is_subscribed_to_newsletter' => 'yes']);
 
 $user->save();
 ```
 
 All fields should now contain a datetime similar to `2018-05-10 16:24:22`.
 
+Note that the date stored in the database column **is immutable, i.e. it's only set once**. Any following updates will not change the stored date(time), unless you update the date column manually or if you set it to `false` and back to `true` (disabling, then enabling it).
+
+For example:
+
+```php
+$user = new User;
+
+$user->has_accepted_terms = true;
+$user->save();
+
+// `accepted_terms_at` column will contain `2022-03-13 13:20:00`
+
+$user->has_accepted_terms = true;
+$user->save();
+
+// `accepted_terms_at` column will still contain the original `2022-03-13 13:20:00` date
+```
+
 ### Clearing saved values
 
 Of course you can also remove the saved date and time, for instance if a user retracts their approval:
@@ -159,13 +189,12 @@ Of course you can also remove the saved date and time, for instance if a user re
 ```php
 $user = User::findOrFail(42);
 
-$user->has_accepted_terms_and_conditions = false;
-// $user->has_accepted_terms_and_conditions = null;
-
-$user->allows_data_processing = 0;
-// $user->allows_data_processing = '0';
-
-$user->has_agreed_to_something = '';
+$user->has_accepted_terms = false;
+$user->has_accepted_terms = null;
+$user->has_accepted_terms = '0';
+$user->has_accepted_terms = 0;
+$user->has_accepted_terms = '';
+// $user->has_accepted_terms = null;
 
 $user->save();
 ```
@@ -181,11 +210,8 @@ Use a boolean field's defined _key_ to access its boolean value:
 ```php
 $user = User::findOrFail(42);
 
-$user->has_accepted_terms_and_conditions;
-
-/*
- * true or false (boolean)
- */
+// true or false (boolean)
+$user->has_accepted_terms;
 ```
 
 #### Retrieving fields as datetimes
@@ -195,22 +221,16 @@ Use a boolean field's defined _value_ to explicitly access its (Carbon) datetime
 ```php
 $user = User::findOrFail(42);
 
+// 2018-05-10 16:24:22 (Carbon or CarbonImmutable instance)
 $user->accepted_terms_at;
 
-/*
- * 2018-05-10 16:24:22 (Carbon instance)
- */
-
-$user->accepted_processing_at;
-
-/*
- * NULL
- */
+// null
+$user->is_subscribed_to_newsletter;
 ```
 
 ### Array conversion
 
-When converting a model to an array, all boolean fields ánd their datetimes will be included:
+When converting a model to an array, the boolean fields will be included if you've added them to the `$appends` array in your model.
 
 ```php
 $user = User::findOrFail(42);
@@ -221,12 +241,10 @@ $user->toArray();
  * Which will return something like:
  * 
  * [
- *     'accepted_terms_at' => \Carbon\Carbon('2018-05-10 16:24:22'),
- *     'accepted_processing_at' => NULL,
- *     'agreed_to_something_at' => \Carbon\Carbon('2018-05-10 16:24:22'),
- *     'accepted_terms_and_conditions' => true,
- *     'allows_data_processing' => false,
- *     'agreed_to_something' => true,
+ *     'accepted_terms_at' => \Carbon\CarbonImmutable('2018-05-10 16:24:22'),
+ *     'subscribed_to_newsletter_at' => \Illuminate\Support\Carbon('2018-05-10 16:24:22'),
+ *     'has_accepted_terms' => true,
+ *     'is_subscribed_to_newsletter' => true,
  * ];
  */
 ```
@@ -282,8 +300,8 @@ Have a project that could use some guidance? Send me an e-mail at [hello@sebasti
 [link-twitter-share]: https://twitter.com/intent/tweet?text=Easily%20convert%20Eloquent%20model%20booleans%20to%20dates%20and%20back%20with%20Laravel%20Boolean%20Dates.%20Via%20@sebastiaanluca%20https://github.com/sebastiaanluca/laravel-boolean-dates
 [link-contributors]: ../../contributors
 
-[link-portfolio]: https://www.sebastiaanluca.com
-[link-blog]: https://blog.sebastiaanluca.com
+[link-portfolio]: https://sebastiaanluca.com
+[link-blog]: https://sebastiaanluca.com/blog
 [link-packages]: https://packagist.org/packages/sebastiaanluca
 [link-twitter]: https://twitter.com/sebastiaanluca
 [link-github-profile]: https://github.com/sebastiaanluca
diff --git a/composer.json b/composer.json
index 7ec60cd..2ec80b4 100644
--- a/composer.json
+++ b/composer.json
@@ -11,6 +11,7 @@
         "eloquent",
         "laravel",
         "model",
+        "php",
         "timestamps"
     ],
     "homepage": "https://github.com/sebastiaanluca/laravel-boolean-dates",
@@ -19,21 +20,18 @@
         {
             "name": "Sebastiaan Luca",
             "email": "hello@sebastiaanluca.com",
-            "homepage": "https://www.sebastiaanluca.com",
+            "homepage": "https://sebastiaanluca.com",
             "role": "Author"
         }
     ],
     "require": {
-        "php": "^7.3",
-        "laravel/framework": "^7.0|^8.0",
-        "nesbot/carbon": "^1.22|^2.0"
+        "php": "^8.0|^8.1",
+        "illuminate/database": "^9.2",
+        "illuminate/support": "^9.2"
     },
     "require-dev": {
-        "dms/phpunit-arraysubset-asserts": "^0.1.0",
-        "kint-php/kint": "^3.3",
-        "mockery/mockery": "^1.3",
-        "orchestra/testbench": "^5.1|^6.0",
-        "phpunit/phpunit": "^8.5"
+        "friendsofphp/php-cs-fixer": "^3.7",
+        "phpunit/phpunit": "^9.5"
     },
     "autoload": {
         "psr-4": {
@@ -48,30 +46,25 @@
     "config": {
         "sort-packages": true
     },
-    "extra": {
-        "laravel": {
-            "providers": [
-                "SebastiaanLuca\\BooleanDates\\BooleanDatesServiceProvider"
-            ]
-        }
-    },
+    "minimum-stability": "dev",
+    "prefer-stable": true,
     "scripts": {
-        "composer-validate": "@composer validate --no-check-all --strict --ansi",
+        "composer:validate": "@composer validate --strict --ansi",
         "test": "vendor/bin/phpunit",
-        "test-lowest": [
-            "composer update --prefer-lowest --prefer-dist --no-interaction --ansi",
+        "lint": "vendor/bin/php-cs-fixer fix --dry-run --diff --ansi",
+        "fix": "vendor/bin/php-cs-fixer fix --ansi",
+        "check": [
+            "@composer:validate",
+            "@lint",
             "@test"
         ],
-        "test-stable": [
-            "composer update --prefer-stable --prefer-dist --no-interaction --ansi",
-            "@test"
+        "check:lowest": [
+            "composer update --prefer-lowest --prefer-dist --no-interaction --ansi",
+            "@check"
         ],
-        "check": [
-            "@composer-validate",
-            "@test"
+        "check:stable": [
+            "composer update --prefer-stable --prefer-dist --no-interaction --ansi",
+            "@check"
         ]
-    },
-    "minimum-stability": "dev",
-    "prefer-stable": true
+    }
 }
-
diff --git a/config/flow.php b/config/flow.php
deleted file mode 100644
index ca5d8ed..0000000
--- a/config/flow.php
+++ /dev/null
@@ -1,5 +0,0 @@
-<?php
-
-return [
-
-];
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
deleted file mode 100644
index 5dacc60..0000000
--- a/phpcs.xml.dist
+++ /dev/null
@@ -1,9 +0,0 @@
-<?xml version="1.0"?>
-<ruleset>
-    <arg name="basepath" value="."/>
-
-    <file>./src</file>
-    <file>./tests</file>
-
-    <rule ref="./vendor/sebastiaanluca/php-codesniffer-ruleset/ruleset.xml"/>
-</ruleset>
diff --git a/phpunit.xml b/phpunit.xml
deleted file mode 100644
index 74a29bd..0000000
--- a/phpunit.xml
+++ /dev/null
@@ -1,32 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<phpunit bootstrap="vendor/autoload.php"
-         backupGlobals="false"
-         backupStaticAttributes="false"
-         colors="true"
-         verbose="true"
-         processIsolation="false"
-         convertErrorsToExceptions="true"
-         convertNoticesToExceptions="true"
-         convertWarningsToExceptions="true"
-         beStrictAboutTestsThatDoNotTestAnything="true"
-         beStrictAboutOutputDuringTests="true"
-         stopOnFailure="false"
-         failOnRisky="true"
-         failOnWarning="true"
-         stopOnError="false"
-         cacheResult="false"
->
-    <testsuites>
-        <testsuite name="Feature Tests">
-            <directory suffix="Test.php">./tests/Feature</directory>
-        </testsuite>
-        <testsuite name="Unit Tests">
-            <directory suffix="Test.php">./tests/Unit</directory>
-        </testsuite>
-    </testsuites>
-    <filter>
-        <whitelist>
-            <directory suffix=".php">src/</directory>
-        </whitelist>
-    </filter>
-</phpunit>
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
new file mode 100644
index 0000000..a753534
--- /dev/null
+++ b/phpunit.xml.dist
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit
+    backupGlobals="false"
+    backupStaticAttributes="false"
+    bootstrap="vendor/autoload.php"
+    colors="true"
+    convertErrorsToExceptions="true"
+    convertNoticesToExceptions="true"
+    convertWarningsToExceptions="true"
+    processIsolation="false"
+    stopOnFailure="false"
+    verbose="true"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd"
+>
+    <coverage>
+        <include>
+            <directory suffix=".php">src/</directory>
+        </include>
+    </coverage>
+    <testsuites>
+        <testsuite name="Feature tests">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>
diff --git a/src/BooleanDateAttribute.php b/src/BooleanDateAttribute.php
new file mode 100644
index 0000000..3ad1847
--- /dev/null
+++ b/src/BooleanDateAttribute.php
@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SebastiaanLuca\BooleanDates;
+
+use Carbon\CarbonImmutable;
+use Illuminate\Database\Eloquent\Casts\Attribute;
+
+class BooleanDateAttribute extends Attribute
+{
+    public static function for(string $column): static
+    {
+        return parent::make(
+            get: static fn (?string $value, array $attributes): bool => static::getBooleanDate($value, $attributes, $column),
+            set: static fn (mixed $value, array $attributes): array => static::setBooleanDate($value, $attributes, $column),
+        );
+    }
+
+    private static function getBooleanDate(mixed $value, array $attributes, string $column): bool
+    {
+        return array_key_exists($column, $attributes) && $attributes[$column] !== null;
+    }
+
+    private static function setBooleanDate(mixed $value, array $attributes, string $column): array
+    {
+        // Only update the field if it's never been set before or when it's being "disabled"
+        if (! $value || ! array_key_exists($column, $attributes) || $attributes[$column] === null) {
+            return [$column => ! $value ? null : CarbonImmutable::now()];
+        }
+
+        return [];
+    }
+}
diff --git a/src/BooleanDatesServiceProvider.php b/src/BooleanDatesServiceProvider.php
deleted file mode 100644
index b40da05..0000000
--- a/src/BooleanDatesServiceProvider.php
+++ /dev/null
@@ -1,11 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates;
-
-use Illuminate\Support\ServiceProvider;
-
-class BooleanDatesServiceProvider extends ServiceProvider
-{
-}
diff --git a/src/HasBooleanDates.php b/src/HasBooleanDates.php
deleted file mode 100644
index 615d03d..0000000
--- a/src/HasBooleanDates.php
+++ /dev/null
@@ -1,188 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates;
-
-use Carbon\Carbon;
-
-trait HasBooleanDates
-{
-    /**
-     * Initialize the trait.
-     *
-     * @return void
-     */
-    public function initializeHasBooleanDates() : void
-    {
-        $this->dates = array_unique(
-            array_merge(
-                $this->dates,
-                array_values($this->getBooleanDates())
-            )
-        );
-    }
-
-    /**
-     * Convert the model's attributes to an array.
-     *
-     * @return array
-     */
-    public function attributesToArray() : array
-    {
-        $attributes = parent::attributesToArray();
-
-        $attributes = $this->addBooleanDateAttributesToArray($attributes);
-
-        return $attributes;
-    }
-
-    /**
-     * Get an attribute from the model.
-     *
-     * @param string $key
-     *
-     * @return mixed
-     */
-    public function getAttribute($key)
-    {
-        if (! $key) {
-            return null;
-        }
-
-        if ($this->hasBooleanDate($key)) {
-            return $this->getBooleanDate($key);
-        }
-
-        return parent::getAttribute($key);
-    }
-
-    /**
-     * Set a given attribute on the model.
-     *
-     * @param string $key
-     * @param mixed $value
-     *
-     * @return $this
-     */
-    public function setAttribute($key, $value)
-    {
-        if ($this->hasBooleanDate($key)) {
-            $this->setBooleanDate($key, $value);
-
-            return $this;
-        }
-
-        return parent::setAttribute($key, $value);
-    }
-
-    /**
-     * @return array
-     */
-    public function getBooleanDates() : array
-    {
-        return $this->booleanDates ?? [];
-    }
-
-    /**
-     * @return array
-     */
-    protected function getBooleanDateAttributes() : array
-    {
-        return array_intersect_key(
-            $this->getAttributes(),
-            array_flip($this->getBooleanDates())
-        );
-    }
-
-    /**
-     * @param mixed $key
-     *
-     * @return bool
-     */
-    protected function getBooleanDate($key) : bool
-    {
-        return parent::getAttribute($this->getBooleanDateField($key)) !== null;
-    }
-
-    /**
-     * @param string $key
-     * @param mixed $value
-     *
-     * @return void
-     */
-    protected function setBooleanDate(string $key, $value) : void
-    {
-        // Only update the timestamp if the value is true and if it's not yet set
-        // or if the value is false and we need to unset the field.
-        if (! $value || ($value && $this->currentBooleanDateFieldValueIsNotYetSet($key))) {
-            // Set the value directly on the attributes array, don't use
-            // setAttribute, and don't receive $200. (\) (°,,,°) (/)
-            // This allows us to format and set the datetime ourselves,
-            // and makes using the $dates field optional.
-            $this->attributes[$this->getBooleanDateField($key)] = $this->getNewBooleanDateValue($value);
-        }
-    }
-
-    /**
-     * @param string $key
-     *
-     * @return bool
-     */
-    protected function hasBooleanDate(string $key) : bool
-    {
-        return array_key_exists($key, $this->getBooleanDates());
-    }
-
-    /**
-     * @param mixed $key
-     *
-     * @return bool
-     */
-    protected function currentBooleanDateFieldValueIsNotYetSet($key) : bool
-    {
-        if (! array_key_exists($this->getBooleanDateField($key), $this->getAttributes())) {
-            return true;
-        }
-
-        return parent::getAttribute($this->getBooleanDateField($key)) === null;
-    }
-
-    /**
-     * @param mixed $key
-     *
-     * @return string
-     */
-    protected function getBooleanDateField($key) : string
-    {
-        return $this->booleanDates[$key];
-    }
-
-    /**
-     * @param mixed $value
-     *
-     * @return string|null
-     */
-    protected function getNewBooleanDateValue($value) : ?string
-    {
-        return $value ? $this->fromDateTime(Carbon::now()) : null;
-    }
-
-    /**
-     * @param array $attributes
-     *
-     * @return array
-     */
-    protected function addBooleanDateAttributesToArray(array $attributes) : array
-    {
-        foreach ($this->getBooleanDates() as $booleanField => $date) {
-            if (! array_key_exists($date, $attributes)) {
-                continue;
-            }
-
-            $attributes[$booleanField] = $this->getBooleanDate($booleanField);
-        }
-
-        return $attributes;
-    }
-}
diff --git a/tests/BooleanAttributeTest.php b/tests/BooleanAttributeTest.php
new file mode 100644
index 0000000..75c253f
--- /dev/null
+++ b/tests/BooleanAttributeTest.php
@@ -0,0 +1,278 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SebastiaanLuca\BooleanDates\Tests;
+
+use Carbon\CarbonImmutable;
+use Illuminate\Support\Carbon;
+
+class BooleanAttributeTest extends TestCase
+{
+    /**
+     * @test
+     */
+    public function it can handle initial values(): void
+    {
+        $model = new TestModel([
+            'accepted_terms_at' => 1,
+            'subscribed_to_newsletter_at' => Carbon::now(),
+        ]);
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+        $this->assertTrue($model->has_accepted_terms);
+
+        $this->assertInstanceOf(Carbon::class, $model->subscribed_to_newsletter_at);
+        $this->assertTrue($model->is_subscribed_to_newsletter);
+    }
+
+    /**
+     * @test
+     */
+    public function it can handle empty initial values(): void
+    {
+        $model = new TestModel;
+
+        $this->assertNull($model->accepted_terms_at);
+        $this->assertFalse($model->has_accepted_terms);
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = false;
+
+        $this->assertNull($model->accepted_terms_at);
+        $this->assertFalse($model->has_accepted_terms);
+
+        $model->has_accepted_terms = true;
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+        $this->assertTrue($model->has_accepted_terms);
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = true;
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+        $this->assertTrue($model->has_accepted_terms);
+
+        $model->has_accepted_terms = false;
+
+        $this->assertNull($model->accepted_terms_at);
+        $this->assertFalse($model->has_accepted_terms);
+    }
+
+    /**
+     * @test
+     */
+    public function it cannot enable a boolean attribute twice and change its date(): void
+    {
+        Carbon::setTestNow('2022-03-13 14:31:00');
+
+        $model = new TestModel;
+
+        $model->has_accepted_terms = true;
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+        $this->assertSame('2022-03-13 14:31:00', $model->accepted_terms_at->toDateTimeString());
+        $this->assertTrue($model->has_accepted_terms);
+
+        $model->has_accepted_terms = true;
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+        $this->assertSame('2022-03-13 14:31:00', $model->accepted_terms_at->toDateTimeString());
+        $this->assertTrue($model->has_accepted_terms);
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute twice if it was disabled(): void
+    {
+        Carbon::setTestNow('2022-03-13 14:00:00');
+
+        $model = new TestModel;
+
+        $model->is_subscribed_to_newsletter = true;
+
+        $this->assertInstanceOf(Carbon::class, $model->subscribed_to_newsletter_at);
+        $this->assertSame('2022-03-13 14:00:00', $model->subscribed_to_newsletter_at->toDateTimeString());
+        $this->assertTrue($model->is_subscribed_to_newsletter);
+
+        Carbon::setTestNow('2022-03-20 15:00:00');
+
+        $model->is_subscribed_to_newsletter = false;
+
+        $this->assertNull($model->subscribed_to_newsletter_at);
+        $this->assertFalse($model->is_subscribed_to_newsletter);
+
+        $model->is_subscribed_to_newsletter = true;
+
+        $this->assertInstanceOf(Carbon::class, $model->subscribed_to_newsletter_at);
+        $this->assertSame('2022-03-20 15:00:00', $model->subscribed_to_newsletter_at->toDateTimeString());
+        $this->assertTrue($model->is_subscribed_to_newsletter);
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute from a boolean(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = true;
+
+        $this->assertInstanceOf(CarbonImmutable::class, $model->accepted_terms_at);
+
+        $this->assertSame(
+            Carbon::now()->format('Y-m-d H:i'),
+            $model->accepted_terms_at->format('Y-m-d H:i')
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute from a string(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = 'yes';
+
+        $this->assertSame(
+            Carbon::now()->format('Y-m-d H:i'),
+            $model->accepted_terms_at->format('Y-m-d H:i')
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute from an integer string(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = '1';
+
+        $this->assertSame(
+            Carbon::now()->format('Y-m-d H:i'),
+            $model->accepted_terms_at->format('Y-m-d H:i')
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function it can enable a boolean attribute from an integer(): void
+    {
+        $model = new TestModel;
+
+        $model->is_subscribed_to_newsletter = 1;
+
+        $this->assertSame(
+            Carbon::now()->format('Y-m-d H:i'),
+            $model->subscribed_to_newsletter_at->format('Y-m-d H:i')
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute from a boolean(): void
+    {
+        $model = new TestModel;
+
+        $model->allows_data_processing = false;
+
+        $this->assertNull($model->accepted_processing_at);
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute from null(): void
+    {
+        $model = new TestModel;
+
+        $model->has_agreed_to_something = null;
+
+        $this->assertNull($model->agreed_to_something_at);
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute from an integer string(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = '0';
+
+        $this->assertNull($model->accepted_terms_at);
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute from an integer(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = 0;
+
+        $this->assertNull($model->accepted_terms_at);
+    }
+
+    /**
+     * @test
+     */
+    public function it can disable a boolean attribute from an empty string(): void
+    {
+        $model = new TestModel;
+
+        $model->has_accepted_terms = '';
+
+        $this->assertNull($model->accepted_terms_at);
+    }
+
+    /**
+     * @test
+     */
+    public function it returns all attributes(): void
+    {
+        Carbon::setTestNow('2018-01-01 10:42:06');
+
+        $model = new TestModel;
+
+        $model->something = 'something';
+
+        $model->has_accepted_terms = 0;
+        $model->is_subscribed_to_newsletter = 1;
+
+        $expected = [
+            'something' => 'something',
+
+            'accepted_terms_at' => null,
+            'subscribed_to_newsletter_at' => '2018-01-01T10:42:06.000000Z',
+
+            'has_accepted_terms' => false,
+            'is_subscribed_to_newsletter' => true,
+        ];
+
+        $this->assertSame(
+            $expected,
+            $model->toArray(),
+        );
+    }
+}
diff --git a/tests/Feature/BooleanArrayTest.php b/tests/Feature/BooleanArrayTest.php
deleted file mode 100644
index 835a55c..0000000
--- a/tests/Feature/BooleanArrayTest.php
+++ /dev/null
@@ -1,69 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates\Tests\Feature;
-
-use Carbon\Carbon;
-use DMS\PHPUnitExtensions\ArraySubset\ArraySubsetAsserts;
-use SebastiaanLuca\BooleanDates\Tests\resources\TestModel;
-use SebastiaanLuca\BooleanDates\Tests\TestCase;
-
-class BooleanArrayTest extends TestCase
-{
-    use ArraySubsetAsserts;
-
-    /**
-     * @test
-     */
-    public function it returns all boolean dates() : void
-    {
-        $model = new TestModel;
-
-        $expected = [
-            'has_accepted_terms_and_conditions' => 'accepted_terms_at',
-            'allows_data_processing' => 'accepted_processing_at',
-            'has_agreed_to_something' => 'agreed_to_something_at',
-        ];
-
-        $this->assertSame(
-            $expected,
-            $model->getBooleanDates()
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it returns all attributes() : void
-    {
-        Carbon::setTestNow('2018-01-01 10:42:06');
-
-        $model = new TestModel;
-
-        $model->something = 'something';
-        $model->tested_at = Carbon::now();
-
-        $model->has_accepted_terms_and_conditions = false;
-        $model->allows_data_processing = true;
-        $model->has_agreed_to_something = '0';
-
-        $expected = [
-            'something' => 'something',
-            'tested_at' => '2018-01-01 10:42:06',
-
-            'has_accepted_terms_and_conditions' => false,
-            'allows_data_processing' => true,
-            'has_agreed_to_something' => false,
-
-            'accepted_terms_at' => null,
-            'accepted_processing_at' => '2018-01-01T10:42:06.000000Z',
-            'agreed_to_something_at' => null,
-        ];
-
-        ArraySubsetAsserts::assertArraySubset(
-            $expected,
-            $model->toArray()
-        );
-    }
-}
diff --git a/tests/Feature/BooleanAttributeTest.php b/tests/Feature/BooleanAttributeTest.php
deleted file mode 100644
index 8b42b4e..0000000
--- a/tests/Feature/BooleanAttributeTest.php
+++ /dev/null
@@ -1,148 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates\Tests\Feature;
-
-use Carbon\Carbon;
-use SebastiaanLuca\BooleanDates\Tests\resources\TestModel;
-use SebastiaanLuca\BooleanDates\Tests\TestCase;
-
-class BooleanAttributeTest extends TestCase
-{
-    /**
-     * @test
-     */
-    public function it skips returning invalid fields() : void
-    {
-        $model = new TestModel;
-
-        $this->assertNull($model->getAttribute(null));
-        $this->assertNull($model->getAttribute(false));
-        $this->assertNull($model->getAttribute(''));
-        $this->assertNull($model->getAttribute('0'));
-    }
-
-    /**
-     * @test
-     */
-    public function it leaves other attributes untouched() : void
-    {
-        $model = new TestModel;
-
-        $model->something = 'something';
-
-        $this->assertSame(
-            'something',
-            $model->something
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it sets the date from a true boolean() : void
-    {
-        $model = new TestModel;
-
-        $model->has_accepted_terms_and_conditions = true;
-
-        $this->assertSame(
-            Carbon::now()->format('Y-m-d H:i'),
-            $model->accepted_terms_at->format('Y-m-d H:i')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it sets the date from a non empty string() : void
-    {
-        $model = new TestModel;
-
-        $model->has_accepted_terms_and_conditions = 'yes';
-
-        $this->assertSame(
-            Carbon::now()->format('Y-m-d H:i'),
-            $model->accepted_terms_at->format('Y-m-d H:i')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it sets the date from a positive integer value() : void
-    {
-        $model = new TestModel;
-
-        $model->has_agreed_to_something = 1;
-
-        $this->assertSame(
-            Carbon::now()->format('Y-m-d H:i'),
-            $model->agreed_to_something_at->format('Y-m-d H:i')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it sets the date from a positive integer string value() : void
-    {
-        $model = new TestModel;
-
-        $model->has_accepted_terms_and_conditions = '1';
-
-        $this->assertSame(
-            Carbon::now()->format('Y-m-d H:i'),
-            $model->accepted_terms_at->format('Y-m-d H:i')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it clears the date from a false boolean() : void
-    {
-        $model = new TestModel;
-
-        $model->allows_data_processing = false;
-
-        $this->assertNull($model->accepted_processing_at);
-    }
-
-    /**
-     * @test
-     */
-    public function it clears the date from null() : void
-    {
-        $model = new TestModel;
-
-        $model->has_agreed_to_something = null;
-
-        $this->assertNull($model->agreed_to_something_at);
-    }
-
-    /**
-     * @test
-     */
-    public function it clears the date from a false string value() : void
-    {
-        $model = new TestModel;
-
-        $model->has_accepted_terms_and_conditions = '0';
-
-        $this->assertNull($model->accepted_terms_at);
-    }
-
-    /**
-     * @test
-     */
-    public function it clears the date from an empty string value() : void
-    {
-        $model = new TestModel;
-
-        $model->has_accepted_terms_and_conditions = '0';
-
-        $this->assertNull($model->accepted_terms_at);
-    }
-}
diff --git a/tests/Feature/BooleanDateTest.php b/tests/Feature/BooleanDateTest.php
deleted file mode 100644
index 1575981..0000000
--- a/tests/Feature/BooleanDateTest.php
+++ /dev/null
@@ -1,59 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates\Tests\Feature;
-
-use Carbon\Carbon;
-use SebastiaanLuca\BooleanDates\Tests\resources\TestModel;
-use SebastiaanLuca\BooleanDates\Tests\TestCase;
-
-class BooleanDateTest extends TestCase
-{
-    /**
-     * @test
-     */
-    public function it leaves other date attributes untouched() : void
-    {
-        $model = new TestModel;
-
-        $model->tested_at = Carbon::now('+5 days');
-
-        $this->assertSame(
-            Carbon::now('+5 days')->format('Y-m-d H:i:s'),
-            $model->tested_at->format('Y-m-d H:i:s')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it returns a date object from a true attribute() : void
-    {
-        $model = new TestModel;
-
-        $model->allows_data_processing = true;
-
-        $this->assertInstanceOf(
-            Carbon::class,
-            $model->accepted_processing_at
-        );
-
-        $this->assertEquals(
-            Carbon::now()->format('Y-m-d H:i:s'),
-            $model->accepted_processing_at->format('Y-m-d H:i:s')
-        );
-    }
-
-    /**
-     * @test
-     */
-    public function it returns null from a false attribute() : void
-    {
-        $model = new TestModel;
-
-        $model->allows_data_processing = false;
-
-        $this->assertNull($model->accepted_processing_at);
-    }
-}
diff --git a/tests/TestCase.php b/tests/TestCase.php
index 0549332..34e1718 100644
--- a/tests/TestCase.php
+++ b/tests/TestCase.php
@@ -4,20 +4,8 @@
 
 namespace SebastiaanLuca\BooleanDates\Tests;
 
-use Orchestra\Testbench\TestCase as BaseTestCase;
-use SebastiaanLuca\BooleanDates\BooleanDatesServiceProvider;
+use PHPUnit\Framework\TestCase as BaseTestCase;
 
 class TestCase extends BaseTestCase
 {
-    /**
-     * @param \Illuminate\Foundation\Application $app
-     *
-     * @return array
-     */
-    protected function getPackageProviders($app) : array
-    {
-        return [
-            BooleanDatesServiceProvider::class,
-        ];
-    }
 }
diff --git a/tests/TestModel.php b/tests/TestModel.php
new file mode 100644
index 0000000..7673bdb
--- /dev/null
+++ b/tests/TestModel.php
@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SebastiaanLuca\BooleanDates\Tests;
+
+use Illuminate\Database\Eloquent\Casts\Attribute;
+use Illuminate\Database\Eloquent\Model;
+use SebastiaanLuca\BooleanDates\BooleanDateAttribute;
+
+class TestModel extends Model
+{
+    /**
+     * @var bool
+     */
+    protected static $unguarded = true;
+
+    /**
+     * The storage format of the model's date columns.
+     *
+     * Set this manually so creating the model with date attributes doesn't
+     * have to check the database.
+     *
+     * @var string
+     */
+    protected $dateFormat = 'Y-m-d H:i:s';
+
+    /**
+     * @var array<string, string>
+     */
+    protected $casts = [
+        'id' => 'integer',
+        'accepted_terms_at' => 'immutable_datetime',
+        'subscribed_to_newsletter_at' => 'datetime',
+    ];
+
+    /**
+     * @var array<int, string>
+     */
+    protected $appends = [
+        'has_accepted_terms',
+        'is_subscribed_to_newsletter',
+    ];
+
+    protected function hasAcceptedTerms(): Attribute
+    {
+        return BooleanDateAttribute::for('accepted_terms_at');
+    }
+
+    protected function isSubscribedToNewsletter(): Attribute
+    {
+        return BooleanDateAttribute::for('subscribed_to_newsletter_at');
+    }
+}
diff --git a/tests/resources/TestModel.php b/tests/resources/TestModel.php
deleted file mode 100644
index 690bcee..0000000
--- a/tests/resources/TestModel.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace SebastiaanLuca\BooleanDates\Tests\resources;
-
-use Illuminate\Database\Eloquent\Model;
-use SebastiaanLuca\BooleanDates\HasBooleanDates;
-
-class TestModel extends Model
-{
-    use HasBooleanDates;
-
-    /**
-     * Set the date of fields to the current date and time if a counterpart boolean field is
-     * true-ish.
-     *
-     * Keys and values should be in the format: `'boolean_field' => 'internal_timestamp_field'`.
-     *
-     * @var array
-     */
-    protected $booleanDates = [
-        'has_accepted_terms_and_conditions' => 'accepted_terms_at',
-        'allows_data_processing' => 'accepted_processing_at',
-        'has_agreed_to_something' => 'agreed_to_something_at',
-    ];
-}