diff --git a/.github/workflows/downgraded_release.yaml b/.github/workflows/downgraded_release.yaml
new file mode 100644
index 0000000..0c2cf23
--- /dev/null
+++ b/.github/workflows/downgraded_release.yaml
@@ -0,0 +1,43 @@
+name: Downgraded Release
+
+on:
+  push:
+    tags:
+      - '*'
+
+permissions:
+  contents: write
+
+jobs:
+  downgrade_release:
+    # Skip if this is already a downgraded tag
+    if: ${{ !endsWith(github.ref_name, '.74') }}
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: shivammathur/setup-php@v2
+        with:
+          php-version: 8.3
+          coverage: none
+
+      - uses: ramsey/composer-install@v3
+
+      # Downgrade /src to PHP 7.4
+      - run: vendor/bin/rector process src --config build/rector-downgrade-php-74.php --ansi
+
+      # Copy PHP 7.4 composer.json
+      - run: cp build/composer-php-74.json composer.json
+
+      # Remove dev files
+      - run: rm -rf build .github tests stubs ecs.php phpstan.neon phpunit.xml rector.php .php-cs-fixer.php
+
+      # Tag and push downgraded code
+      - name: Tag Downgraded Code
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+          git add --all
+          git commit -m "release PHP 7.4 downgraded version" || echo "No changes to commit"
+          git tag "${GITHUB_REF#refs/tags/}.74"
+          git push origin "${GITHUB_REF#refs/tags/}.74"
diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index f221f07..3abc8b4 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -27,16 +27,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-version:
-          - "7.4"
-          - "8.0"
-          - "8.1"
-          - "8.2"
-          - "8.3"
-          - "8.4"
-        dependencies:
-          - lowest
-          - highest
+        php-version: ["8.1", "8.2", "8.3", "8.4"]
+        dependencies: [lowest, highest]
 
     steps:
       - uses: actions/checkout@v4
@@ -47,19 +39,6 @@ jobs:
           extensions: mbstring
           php-version: "${{ matrix.php-version }}"
 
-      - if: matrix.php-version == '7.4'
-        run: >
-          composer remove --dev --no-update
-          rector/rector
-          mll-lab/graphql-php-scalars
-          spaze/phpstan-disallowed-calls
-
-      - if: matrix.php-version == '8.0'
-        run: composer remove --dev --no-update rector/rector
-
-      - if: matrix.php-version == '7.4' || matrix.php-version == '8.0'
-        run: rm -rf src/Enum tests/Enum src/FluidXPlate/Scalars src/Microplate/Scalars tests/FluidXPlate/Scalars tests/Microplate/Scalars
-
       - uses: ramsey/composer-install@v3
         with:
           dependency-versions: "${{ matrix.dependencies }}"
@@ -74,16 +53,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-version:
-          - "7.4"
-          - "8.0"
-          - "8.1"
-          - "8.2"
-          - "8.3"
-          - "8.4"
-        dependencies:
-          - lowest
-          - highest
+        php-version: ["8.1", "8.2", "8.3", "8.4"]
+        dependencies: [lowest, highest]
 
     steps:
       - uses: actions/checkout@v4
@@ -94,19 +65,6 @@ jobs:
           extensions: mbstring
           php-version: "${{ matrix.php-version }}"
 
-      - if: matrix.php-version == '7.4'
-        run: >
-          composer remove --dev --no-update
-          rector/rector
-          mll-lab/graphql-php-scalars
-          spaze/phpstan-disallowed-calls
-
-      - if: matrix.php-version == '8.0'
-        run: composer remove --dev --no-update rector/rector
-
-      - if: matrix.php-version == '7.4' || matrix.php-version == '8.0'
-        run: rm -rf src/Enum tests/Enum src/FluidXPlate/Scalars src/Microplate/Scalars tests/FluidXPlate/Scalars tests/Microplate/Scalars
-
       - uses: ramsey/composer-install@v3
         with:
           dependency-versions: "${{ matrix.dependencies }}"
@@ -131,3 +89,56 @@ jobs:
 
       # Not using v4 due to the breaking changes described in https://github.com/codecov/codecov-action/releases/tag/v4.0.0
       - uses: codecov/codecov-action@v3
+
+  downgraded-build-validate:
+    name: "Downgraded Build Validate (PHP 7.4, ${{ matrix.dependencies }})"
+    runs-on: ubuntu-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        dependencies: [lowest, highest]
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: "Setup PHP 8.3 (Rector)"
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: 8.3
+          coverage: none
+
+      - uses: ramsey/composer-install@v3
+
+      - name: "Downgrade src and tests"
+        run: |
+          vendor/bin/rector process src tests --config build/rector-downgrade-php-74.php --ansi
+
+      - name: "Prepare downgraded composer.json"
+        run: |
+          cp build/composer-php-74.json composer.json
+          rm -f composer.lock
+
+      - name: "Remove tests incompatible with PHP 7.4"
+        run: |
+          rm -rf tests/PHPStan              # Requires PHPStan testing framework
+          rm -rf tests/Enum                 # PHP 8.1+ enums cannot be downgraded
+          rm -rf tests/FluidXPlate          # Requires graphql-php-scalars (optional)
+          rm -rf tests/Qiaxcel              # Requires phpspreadsheet (optional)
+          rm -rf tests/LightcyclerExportSheet  # Uses Collection::firstOrFail (Laravel 9+)
+
+      - name: "Setup PHP 7.4"
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: 7.4
+          coverage: none
+
+      - name: "Install downgraded dependencies"
+        run: |
+          composer update --no-interaction --prefer-dist ${{ matrix.dependencies == 'lowest' && '--prefer-lowest --prefer-stable' || '' }}
+
+      - name: "Validate downgraded composer.json"
+        run: composer validate --no-check-publish
+
+      - name: "Run PHPUnit on downgraded src"
+        run: vendor/bin/phpunit
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 502082a..211e886 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,22 @@
+## v6.0.0
+
+### Changed
+
+- Require PHP ^8.1 for the main package
+- Use PHP 8.1 features: `readonly` properties, union type syntax
+
+### Added
+
+- Automatic PHP 7.4 downgraded releases via `.74` tag suffix (e.g., `v6.0.0.74`)
+- GitHub Actions workflow for automated downgrade releases
+
+### Migration
+
+Users on PHP 7.4 or 8.0 should use the `.74` tagged releases:
+```sh
+composer require mll-lab/php-utils:v6.0.0.74
+```
+
 # [5.23.0](https://github.com/mll-lab/php-utils/compare/v5.22.0...v5.23.0) (2025-12-08)
 
 
diff --git a/README.md b/README.md
index 3cc88c1..d756a4b 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,16 @@ Install through composer
 composer require mll-lab/php-utils
 ```
 
+### PHP 7.4 / 8.0 Support
+
+The main package requires PHP ^8.1. For PHP 7.4 or 8.0, use the automatically generated `.74` releases:
+
+```sh
+composer require mll-lab/php-utils:v6.0.0.74
+```
+
+These releases are automatically downgraded using [Rector](https://getrector.org) and published alongside each main release.
+
 ## Usage
 
 See [tests](tests).
diff --git a/build/composer-php-74.json b/build/composer-php-74.json
new file mode 100644
index 0000000..30d01a4
--- /dev/null
+++ b/build/composer-php-74.json
@@ -0,0 +1,63 @@
+{
+  "name": "mll-lab/php-utils",
+  "description": "Shared PHP utility functions of MLL",
+  "license": "MIT",
+  "type": "library",
+  "authors": [
+    {
+      "name": "Benedikt Franke",
+      "email": "benedikt@franke.tech"
+    }
+  ],
+  "homepage": "https://github.com/mll-lab/php-utils",
+  "support": {
+    "issues": "https://github.com/mll-lab/php-utils/issues",
+    "source": "https://github.com/mll-lab/php-utils"
+  },
+  "require": {
+    "php": "^7.4 || ^8.0",
+    "ext-calendar": "*",
+    "ext-simplexml": "*",
+    "illuminate/support": "^8.77 || ^9 || ^10",
+    "mll-lab/str_putcsv": "^1",
+    "nesbot/carbon": "^2.62.1",
+    "ramsey/uuid": "^3 || ^4",
+    "thecodingmachine/safe": "^1 || ^2"
+  },
+  "require-dev": {
+    "phpunit/phpunit": "^9.6"
+  },
+  "suggest": {
+    "mll-lab/graphql-php-scalars": "To use the provided scalar types for GraphQL servers, requires version ^6.3",
+    "phpoffice/phpspreadsheet": "Required if using QiaxcelImport",
+    "spaze/phpstan-disallowed-calls": "Required when using the PHPStan configuration from rules.neon directly or through the extension installer"
+  },
+  "autoload": {
+    "psr-4": {
+      "MLL\\Utils\\": "src/"
+    }
+  },
+  "autoload-dev": {
+    "psr-4": {
+      "MLL\\Utils\\Tests\\": "tests/"
+    }
+  },
+  "config": {
+    "audit": {
+      "ignore": [
+        "PKSA-8qx3-n5y5-vvnd"
+      ],
+      "abandoned": "ignore"
+    },
+    "block-insecure": false,
+    "sort-packages": true
+  },
+  "extra": {
+    "phpstan": {
+      "includes": [
+        "extension.neon",
+        "rules.neon"
+      ]
+    }
+  }
+}
diff --git a/build/rector-downgrade-php-74.php b/build/rector-downgrade-php-74.php
new file mode 100644
index 0000000..ba8312c
--- /dev/null
+++ b/build/rector-downgrade-php-74.php
@@ -0,0 +1,14 @@
+<?php declare(strict_types=1);
+
+use Rector\Config\RectorConfig;
+use Rector\DowngradePhp80\Rector\Class_\DowngradeAttributeToAnnotationRector;
+use Rector\DowngradePhp80\ValueObject\DowngradeAttributeToAnnotation;
+
+return RectorConfig::configure()
+    ->withDowngradeSets(php74: true)
+    ->withConfiguredRule(DowngradeAttributeToAnnotationRector::class, [
+        new DowngradeAttributeToAnnotation(
+            'PHPUnit\Framework\Attributes\DataProvider',
+            'dataProvider'
+        ),
+    ]);
diff --git a/composer.json b/composer.json
index 9f3cb7c..362bfbc 100644
--- a/composer.json
+++ b/composer.json
@@ -15,10 +15,10 @@
     "source": "https://github.com/mll-lab/php-utils"
   },
   "require": {
-    "php": "^7.4 || ^8",
+    "php": "^8.1",
     "ext-calendar": "*",
     "ext-simplexml": "*",
-    "illuminate/support": "^8.73 || ^9 || ^10 || ^11 || ^12",
+    "illuminate/support": "^8.77 || ^9 || ^10 || ^11 || ^12",
     "mll-lab/str_putcsv": "^1",
     "nesbot/carbon": "^2.62.1 || ^3",
     "ramsey/uuid": "^3 || ^4",
diff --git a/rector.php b/rector.php
index 88c0015..d068315 100644
--- a/rector.php
+++ b/rector.php
@@ -9,6 +9,8 @@
         SetList::CODE_QUALITY,
         SetList::TYPE_DECLARATION,
         SetList::RECTOR_PRESET,
+        SetList::PHP_80,
+        SetList::PHP_81,
         PHPUnitSetList::PHPUNIT_40,
         PHPUnitSetList::PHPUNIT_50,
         PHPUnitSetList::PHPUNIT_60,
@@ -19,7 +21,6 @@
         PHPUnitSetList::PHPUNIT_110,
         PHPUnitSetList::PHPUNIT_CODE_QUALITY,
     ])
-    ->withPhpSets()
     ->withRules([
         Rector\PHPUnit\CodeQuality\Rector\Class_\PreferPHPUnitSelfCallRector::class,
     ])
@@ -28,6 +29,9 @@
         Rector\CodeQuality\Rector\Concat\JoinStringConcatRector::class => [
             __DIR__ . '/tests/CSVArrayTest.php', // keep `\r\n` for readability
         ],
+        Rector\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector::class => [
+            __DIR__ . '/src/IlluminaSampleSheet/V2/BclConvert/BclSample.php', // currently relies on `get_object_vars()` and breaks behaviour.
+        ],
     ])
     ->withPaths([__DIR__ . '/src', __DIR__ . '/tests'])
     ->withBootstrapFiles([
diff --git a/src/DnaSequence.php b/src/DnaSequence.php
index ee71da4..03cc976 100644
--- a/src/DnaSequence.php
+++ b/src/DnaSequence.php
@@ -19,7 +19,7 @@ public function reverse(): string
         $parts = mb_str_split($this->sequence); // @phpstan-ignore-line theCodingMachineSafe.function (safe from PHP 8.0)
         $reversedParts = array_reverse($parts);
 
-        return implode($reversedParts);
+        return implode('', $reversedParts);
     }
 
     public function complement(): string
diff --git a/src/FluidXPlate/FluidXPlate.php b/src/FluidXPlate/FluidXPlate.php
index 195e007..c484c6d 100644
--- a/src/FluidXPlate/FluidXPlate.php
+++ b/src/FluidXPlate/FluidXPlate.php
@@ -16,7 +16,7 @@ class FluidXPlate
     public string $rackID;
 
     /** @var Microplate<string, CoordinateSystem12x8> */
-    private Microplate $microplate;
+    private readonly Microplate $microplate;
 
     public function __construct(string $rackID)
     {
@@ -51,7 +51,7 @@ public function addToNextFreeWell(string $content, FlowDirection $flowDirection)
     /** @return Collection<string, string|null> */
     public function wells(): Collection
     {
-        return $this->microplate->wells();
+        return $this->microplate->wells(); // @phpstan-ignore return.type (generic not inferred)
     }
 
     /** @return Collection<string, null> */
@@ -63,6 +63,6 @@ public function freeWells(): Collection
     /** @return Collection<string, string> */
     public function filledWells(): Collection
     {
-        return $this->microplate->filledWells();
+        return $this->microplate->filledWells(); // @phpstan-ignore return.type (generic not inferred)
     }
 }
diff --git a/src/IlluminaSampleSheet/V1/DualIndex.php b/src/IlluminaSampleSheet/V1/DualIndex.php
index 0b993eb..f88df26 100644
--- a/src/IlluminaSampleSheet/V1/DualIndex.php
+++ b/src/IlluminaSampleSheet/V1/DualIndex.php
@@ -4,21 +4,12 @@
 
 class DualIndex extends Index
 {
-    public string $i7IndexID;
-
-    public string $index;
-
-    public string $i5IndexID;
-
-    public string $index2;
-
-    public function __construct(string $i7IndexID, string $index, string $i5IndexID, string $index2)
-    {
-        $this->i7IndexID = $i7IndexID;
-        $this->index = $index;
-        $this->i5IndexID = $i5IndexID;
-        $this->index2 = $index2;
-
+    public function __construct(
+        public string $i7IndexID,
+        public string $index,
+        public string $i5IndexID,
+        public string $index2
+    ) {
         $this->validate();
     }
 
diff --git a/src/IlluminaSampleSheet/V1/HeaderSection.php b/src/IlluminaSampleSheet/V1/HeaderSection.php
index 208d820..b5c8994 100644
--- a/src/IlluminaSampleSheet/V1/HeaderSection.php
+++ b/src/IlluminaSampleSheet/V1/HeaderSection.php
@@ -6,45 +6,17 @@
 
 class HeaderSection implements Section
 {
-    public ?string $iemFileVersion;
-
-    public ?string $experimentName;
-
-    public ?string $investigatorName;
-
-    public string $date;
-
-    public string $workflow;
-
-    public string $application;
-
-    public string $assay;
-
-    public string $description;
-
-    public string $chemistry;
-
     public function __construct(
-        string $iemFileVersion,
-        string $investigatorName,
-        string $experimentName,
-        string $date,
-        string $workflow,
-        string $application,
-        string $assay,
-        string $description,
-        string $chemistry
-    ) {
-        $this->chemistry = $chemistry;
-        $this->description = $description;
-        $this->assay = $assay;
-        $this->application = $application;
-        $this->workflow = $workflow;
-        $this->date = $date;
-        $this->investigatorName = $investigatorName;
-        $this->experimentName = $experimentName;
-        $this->iemFileVersion = $iemFileVersion;
-    }
+        public ?string $iemFileVersion,
+        public ?string $investigatorName,
+        public ?string $experimentName,
+        public string $date,
+        public string $workflow,
+        public string $application,
+        public string $assay,
+        public string $description,
+        public string $chemistry
+    ) {}
 
     public function convertSectionToString(): string
     {
diff --git a/src/IlluminaSampleSheet/V1/ReadsSection.php b/src/IlluminaSampleSheet/V1/ReadsSection.php
index fcde207..f0fea7d 100644
--- a/src/IlluminaSampleSheet/V1/ReadsSection.php
+++ b/src/IlluminaSampleSheet/V1/ReadsSection.php
@@ -6,15 +6,10 @@
 
 class ReadsSection implements Section
 {
-    private int $read1Cycles;
-
-    private int $read2Cycles;
-
-    public function __construct(int $read1Cycles, int $read2Cycles)
-    {
-        $this->read1Cycles = $read1Cycles;
-        $this->read2Cycles = $read2Cycles;
-    }
+    public function __construct(
+        private readonly int $read1Cycles,
+        private readonly int $read2Cycles
+    ) {}
 
     public function convertSectionToString(): string
     {
diff --git a/src/IlluminaSampleSheet/V1/RowForDualIndexWithLane.php b/src/IlluminaSampleSheet/V1/RowForDualIndexWithLane.php
index de197ce..29ea0d3 100644
--- a/src/IlluminaSampleSheet/V1/RowForDualIndexWithLane.php
+++ b/src/IlluminaSampleSheet/V1/RowForDualIndexWithLane.php
@@ -4,30 +4,17 @@
 
 class RowForDualIndexWithLane extends Row
 {
-    public DualIndex $dualIndex;
-
-    public int $lane;
-
-    public string $sampleName;
-
-    public string $samplePlate;
-
-    public string $sampleWell;
-
-    public string $sampleProject;
-
-    public string $description;
-
-    public function __construct(DualIndex $dualIndex, int $lane, string $sampleID, string $sampleName, string $samplePlate, string $sampleWell, string $sampleProject, string $description)
-    {
-        $this->dualIndex = $dualIndex;
-        $this->lane = $lane;
+    public function __construct(
+        public DualIndex $dualIndex,
+        public int $lane,
+        string $sampleID,
+        public string $sampleName,
+        public string $samplePlate,
+        public string $sampleWell,
+        public string $sampleProject,
+        public string $description
+    ) {
         $this->sampleID = $sampleID;
-        $this->sampleName = $sampleName;
-        $this->samplePlate = $samplePlate;
-        $this->sampleWell = $sampleWell;
-        $this->sampleProject = $sampleProject;
-        $this->description = $description;
     }
 
     public function toString(): string
diff --git a/src/IlluminaSampleSheet/V1/RowForDualIndexWithoutLane.php b/src/IlluminaSampleSheet/V1/RowForDualIndexWithoutLane.php
index 2d0c6dc..4a24a63 100644
--- a/src/IlluminaSampleSheet/V1/RowForDualIndexWithoutLane.php
+++ b/src/IlluminaSampleSheet/V1/RowForDualIndexWithoutLane.php
@@ -4,27 +4,16 @@
 
 class RowForDualIndexWithoutLane extends Row
 {
-    public DualIndex $dualIndex;
-
-    public string $sampleName;
-
-    public string $samplePlate;
-
-    public string $sampleWell;
-
-    public string $sampleProject;
-
-    public string $description;
-
-    public function __construct(DualIndex $dualIndex, string $sampleID, string $sampleName, string $samplePlate, string $sampleWell, string $sampleProject, string $description)
-    {
-        $this->dualIndex = $dualIndex;
+    public function __construct(
+        public DualIndex $dualIndex,
+        string $sampleID,
+        public string $sampleName,
+        public string $samplePlate,
+        public string $sampleWell,
+        public string $sampleProject,
+        public string $description
+    ) {
         $this->sampleID = $sampleID;
-        $this->sampleName = $sampleName;
-        $this->samplePlate = $samplePlate;
-        $this->sampleWell = $sampleWell;
-        $this->sampleProject = $sampleProject;
-        $this->description = $description;
     }
 
     public function toString(): string
diff --git a/src/IlluminaSampleSheet/V1/SettingsSection.php b/src/IlluminaSampleSheet/V1/SettingsSection.php
index 6fc8b61..0744373 100644
--- a/src/IlluminaSampleSheet/V1/SettingsSection.php
+++ b/src/IlluminaSampleSheet/V1/SettingsSection.php
@@ -6,15 +6,10 @@
 
 class SettingsSection implements Section
 {
-    private ?string $adapter;
-
-    private ?string $adapterRead2;
-
-    public function __construct(?string $adapter = null, ?string $adapterRead2 = null)
-    {
-        $this->adapter = $adapter;
-        $this->adapterRead2 = $adapterRead2;
-    }
+    public function __construct(
+        private readonly ?string $adapter = null,
+        private readonly ?string $adapterRead2 = null
+    ) {}
 
     public function convertSectionToString(): string
     {
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/BclConvertSection.php b/src/IlluminaSampleSheet/V2/BclConvert/BclConvertSection.php
index e98757a..70caaa4 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/BclConvertSection.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/BclConvertSection.php
@@ -7,15 +7,10 @@
 
 class BclConvertSection implements Section
 {
-    protected SettingsSection $settingsSection;
-
-    protected DataSection $dataSection;
-
-    public function __construct(SettingsSection $settingsSection, DataSection $dataSection)
-    {
-        $this->settingsSection = $settingsSection;
-        $this->dataSection = $dataSection;
-    }
+    public function __construct(
+        protected SettingsSection $settingsSection,
+        protected DataSection $dataSection
+    ) {}
 
     public function convertSectionToString(): string
     {
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/CycleType.php b/src/IlluminaSampleSheet/V2/BclConvert/CycleType.php
index f26983d..614b196 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/CycleType.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/CycleType.php
@@ -9,12 +9,9 @@ class CycleType
     public const UMI_CYCLE = 'U';
     public const INDEX_CYCLE = 'I';
 
-    public string $value;
-
-    public function __construct(string $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public string $value
+    ) {}
 
     public static function READ_CYCLE(): self
     {
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/CycleTypeWithCount.php b/src/IlluminaSampleSheet/V2/BclConvert/CycleTypeWithCount.php
index 039da11..2681721 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/CycleTypeWithCount.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/CycleTypeWithCount.php
@@ -4,15 +4,10 @@
 
 class CycleTypeWithCount
 {
-    protected CycleType $cycleType;
-
-    public int $count;
-
-    public function __construct(CycleType $cycleType, int $count)
-    {
-        $this->cycleType = $cycleType;
-        $this->count = $count;
-    }
+    public function __construct(
+        protected CycleType $cycleType,
+        public int $count
+    ) {}
 
     public function toString(): string
     {
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/DataSection.php b/src/IlluminaSampleSheet/V2/BclConvert/DataSection.php
index db3fc4f..a67d0f1 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/DataSection.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/DataSection.php
@@ -59,7 +59,7 @@ protected function generateDataHeaderByProperties(array $samplePropertiesOfFirst
         $samplePropertiesOfFirstSample = array_filter($samplePropertiesOfFirstSample, fn (string $value): bool // @phpstan-ignore-next-line Variable property access on a non-object required here
         => $this->dataRows[0]->$value !== null);
 
-        $samplePropertiesOfFirstSample = array_map(fn (string $value): string => ucfirst($value), $samplePropertiesOfFirstSample);
+        $samplePropertiesOfFirstSample = array_map(ucfirst(...), $samplePropertiesOfFirstSample);
 
         return implode(',', $samplePropertiesOfFirstSample);
     }
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycle.php b/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycle.php
index 54c035b..819998a 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycle.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycle.php
@@ -6,14 +6,10 @@
 
 class OverrideCycle
 {
-    /** @var array<CycleTypeWithCount> */
-    public array $cycles;
-
     /** @param array<CycleTypeWithCount> $cycles */
-    public function __construct(array $cycles)
-    {
-        $this->cycles = $cycles;
-    }
+    public function __construct(
+        public array $cycles
+    ) {}
 
     /** @param bool|null $isSecondIndexAndForwardDirection null if it is not the secondIndex, true if it is the secondIndex and forwardDirection, false if it is the secondIndex and reverseDirection */
     public function toString(int $fillUpToMax, ?bool $isSecondIndexAndForwardDirection): string
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycles.php b/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycles.php
index 03715cf..617f482 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycles.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/OverrideCycles.php
@@ -15,15 +15,17 @@ class OverrideCycles
 
     public ?OverrideCycle $read2;
 
-    private DataSection $dataSection;
-
-    public function __construct(DataSection $dataSection, string $read1, string $index1, ?string $index2, ?string $read2)
-    {
+    public function __construct(
+        private readonly DataSection $dataSection,
+        string $read1,
+        string $index1,
+        ?string $index2,
+        ?string $read2
+    ) {
         $this->read1 = $this->makeOverrideCycle($read1);
         $this->index1 = $this->makeOverrideCycle($index1);
         $this->index2 = $index2 !== null ? $this->makeOverrideCycle($index2) : null;
         $this->read2 = $read2 !== null ? $this->makeOverrideCycle($read2) : null;
-        $this->dataSection = $dataSection;
     }
 
     public function toString(): string
diff --git a/src/IlluminaSampleSheet/V2/BclConvert/SettingsSection.php b/src/IlluminaSampleSheet/V2/BclConvert/SettingsSection.php
index 7279c24..b248c2f 100644
--- a/src/IlluminaSampleSheet/V2/BclConvert/SettingsSection.php
+++ b/src/IlluminaSampleSheet/V2/BclConvert/SettingsSection.php
@@ -7,19 +7,12 @@
 
 class SettingsSection implements Section
 {
-    public string $softwareVersion;
-
-    public FastQCompressionFormat $fastqCompressionFormat;
-
     public ?bool $trimUMI = null;
 
     public function __construct(
-        string $softwareVersion,
-        FastQCompressionFormat $fastqCompressionFormat
-    ) {
-        $this->softwareVersion = $softwareVersion;
-        $this->fastqCompressionFormat = $fastqCompressionFormat;
-    }
+        public string $softwareVersion,
+        public FastQCompressionFormat $fastqCompressionFormat
+    ) {}
 
     public function convertSectionToString(): string
     {
diff --git a/src/IlluminaSampleSheet/V2/Enums/FastQCompressionFormat.php b/src/IlluminaSampleSheet/V2/Enums/FastQCompressionFormat.php
index d813820..aed0df4 100644
--- a/src/IlluminaSampleSheet/V2/Enums/FastQCompressionFormat.php
+++ b/src/IlluminaSampleSheet/V2/Enums/FastQCompressionFormat.php
@@ -7,12 +7,9 @@ class FastQCompressionFormat
     public const GZIP = 'gzip';
     public const DRAGEN = 'dragen';
 
-    public string $value;
-
-    public function __construct(string $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public string $value
+    ) {}
 
     public static function GZIP(): self
     {
diff --git a/src/IlluminaSampleSheet/V2/HeaderSection.php b/src/IlluminaSampleSheet/V2/HeaderSection.php
index 8731f43..3159036 100644
--- a/src/IlluminaSampleSheet/V2/HeaderSection.php
+++ b/src/IlluminaSampleSheet/V2/HeaderSection.php
@@ -11,8 +11,6 @@ class HeaderSection implements Section
 
     protected string $fileFormatVersion = self::FILE_FORMAT_VERSION;
 
-    public string $runName;
-
     public ?string $runDescription = null;
 
     public ?string $instrumentType = null;
@@ -22,10 +20,9 @@ class HeaderSection implements Section
     /** @var array<string, string> */
     protected array $customParams = [];
 
-    public function __construct(string $runName)
-    {
-        $this->runName = $runName;
-    }
+    public function __construct(
+        public string $runName
+    ) {}
 
     public static function isForwardIndexOrientation(): bool
     {
diff --git a/src/LightcyclerExportSheet/LightcyclerSample.php b/src/LightcyclerExportSheet/LightcyclerSample.php
index 2e5e3f0..52a6437 100644
--- a/src/LightcyclerExportSheet/LightcyclerSample.php
+++ b/src/LightcyclerExportSheet/LightcyclerSample.php
@@ -7,29 +7,12 @@
 
 class LightcyclerSample
 {
-    public string $name;
-
-    /** @var Coordinates<CoordinateSystem12x8> */
-    public Coordinates $coordinates;
-
-    public float $calculatedConcentration;
-
-    public float $crossingPoint;
-
-    public ?float $standardConcentration;
-
     /** @param Coordinates<CoordinateSystem12x8> $coordinates */
     public function __construct(
-        string $name,
-        Coordinates $coordinates,
-        float $calculatedConcentration,
-        float $crossingPoint,
-        ?float $standardConcentration = null
-    ) {
-        $this->standardConcentration = $standardConcentration;
-        $this->crossingPoint = $crossingPoint;
-        $this->calculatedConcentration = $calculatedConcentration;
-        $this->coordinates = $coordinates;
-        $this->name = $name;
-    }
+        public string $name,
+        public Coordinates $coordinates,
+        public float $calculatedConcentration,
+        public float $crossingPoint,
+        public ?float $standardConcentration = null
+    ) {}
 }
diff --git a/src/LightcyclerSampleSheet/AbsoluteQuantificationSample.php b/src/LightcyclerSampleSheet/AbsoluteQuantificationSample.php
index 9a236b8..08b7e88 100644
--- a/src/LightcyclerSampleSheet/AbsoluteQuantificationSample.php
+++ b/src/LightcyclerSampleSheet/AbsoluteQuantificationSample.php
@@ -7,34 +7,15 @@
 
 class AbsoluteQuantificationSample
 {
-    public string $sampleName;
-
-    public string $filterCombination;
-
-    public string $hexColor;
-
-    public string $sampleType;
-
-    /** Key used to determine replication grouping - samples with the same key will replicate to the first occurrence */
-    public string $replicationOfKey;
-
-    public ?int $concentration;
-
     public function __construct(
-        string $sampleName,
-        string $filterCombination,
-        string $hexColor,
-        string $sampleType,
-        string $replicationOfKey,
-        ?int $concentration
-    ) {
-        $this->sampleName = $sampleName;
-        $this->filterCombination = $filterCombination;
-        $this->hexColor = $hexColor;
-        $this->sampleType = $sampleType;
-        $this->replicationOfKey = $replicationOfKey;
-        $this->concentration = $concentration;
-    }
+        public string $sampleName,
+        public string $filterCombination,
+        public string $hexColor,
+        public string $sampleType,
+        /** Key used to determine replication grouping - samples with the same key will replicate to the first occurrence */
+        public string $replicationOfKey,
+        public ?int $concentration
+    ) {}
 
     public static function formatConcentration(?int $concentration): ?string
     {
diff --git a/src/LightcyclerSampleSheet/RelativeQuantificationSample.php b/src/LightcyclerSampleSheet/RelativeQuantificationSample.php
index d686997..0038f78 100644
--- a/src/LightcyclerSampleSheet/RelativeQuantificationSample.php
+++ b/src/LightcyclerSampleSheet/RelativeQuantificationSample.php
@@ -7,27 +7,13 @@
 
 class RelativeQuantificationSample
 {
-    public string $sampleName;
-
-    public string $filterCombination;
-
-    public string $hexColor;
-
-    /** @var Coordinates<CoordinateSystem12x8>|null */
-    public ?Coordinates $replicationOf;
-
     /** @param Coordinates<CoordinateSystem12x8>|null $replicationOf */
     public function __construct(
-        string $sampleName,
-        string $filterCombination,
-        string $hexColor,
-        ?Coordinates $replicationOf
-    ) {
-        $this->sampleName = $sampleName;
-        $this->filterCombination = $filterCombination;
-        $this->hexColor = $hexColor;
-        $this->replicationOf = $replicationOf;
-    }
+        public string $sampleName,
+        public string $filterCombination,
+        public string $hexColor,
+        public ?Coordinates $replicationOf
+    ) {}
 
     /** @return list<string> */
     public function toSerializableArray(string $coordinatesString): array
diff --git a/src/Microplate/AbstractMicroplate.php b/src/Microplate/AbstractMicroplate.php
index c8f5178..7cb7f02 100644
--- a/src/Microplate/AbstractMicroplate.php
+++ b/src/Microplate/AbstractMicroplate.php
@@ -16,14 +16,10 @@ abstract class AbstractMicroplate
 {
     public const EMPTY_WELL = null;
 
-    /** @var TCoordinateSystem */
-    public CoordinateSystem $coordinateSystem;
-
     /** @param TCoordinateSystem $coordinateSystem */
-    public function __construct(CoordinateSystem $coordinateSystem)
-    {
-        $this->coordinateSystem = $coordinateSystem;
-    }
+    public function __construct(
+        public CoordinateSystem $coordinateSystem
+    ) {}
 
     /** @return WellsCollection */
     abstract public function wells(): Collection;
diff --git a/src/Microplate/AbstractSection.php b/src/Microplate/AbstractSection.php
index 8b66b8f..8592851 100644
--- a/src/Microplate/AbstractSection.php
+++ b/src/Microplate/AbstractSection.php
@@ -7,16 +7,13 @@
 /** @template TSectionWell */
 abstract class AbstractSection
 {
-    /** @var SectionedMicroplate<TSectionWell, CoordinateSystem, static> */
-    public SectionedMicroplate $sectionedMicroplate;
-
     /** @var Collection<int, TSectionWell|null> */
     public Collection $sectionItems;
 
     /** @param SectionedMicroplate<TSectionWell, CoordinateSystem, static> $sectionedMicroplate */
-    public function __construct(SectionedMicroplate $sectionedMicroplate)
-    {
-        $this->sectionedMicroplate = $sectionedMicroplate;
+    public function __construct(
+        public SectionedMicroplate $sectionedMicroplate
+    ) {
         $this->sectionItems = new Collection();
     }
 
diff --git a/src/Microplate/Coordinates.php b/src/Microplate/Coordinates.php
index a13c7b4..0fdb73b 100644
--- a/src/Microplate/Coordinates.php
+++ b/src/Microplate/Coordinates.php
@@ -84,7 +84,7 @@ public static function fromString(string $coordinatesString, CoordinateSystem $c
         if ($valid === 0) {
             $firstValidExample = Arr::first($rows) . Arr::first($columns);
             $lastValidExample = Arr::last($rows) . Arr::last($columns);
-            $coordinateSystemClass = get_class($coordinateSystem);
+            $coordinateSystemClass = $coordinateSystem::class;
             throw new \InvalidArgumentException("Expected coordinates between {$firstValidExample} and {$lastValidExample} for {$coordinateSystemClass}, got: {$coordinatesString}.");
         }
         /** @var array{1: string, 2: string} $matches */
@@ -103,25 +103,19 @@ public static function fromPosition(int $position, FlowDirection $direction, Coo
     {
         self::assertPositionInRange($coordinateSystem, $position);
 
-        switch ($direction->value) {
-            case FlowDirection::COLUMN:
-                return new static(
-                    $coordinateSystem->rowForColumnFlowPosition($position),
-                    $coordinateSystem->columnForColumnFlowPosition($position),
-                    $coordinateSystem
-                );
-
-            case FlowDirection::ROW:
-                return new static(
-                    $coordinateSystem->rowForRowFlowPosition($position),
-                    $coordinateSystem->columnForRowFlowPosition($position),
-                    $coordinateSystem
-                );
-                // @codeCoverageIgnoreStart all Enums are listed and this should never happen
-            default:
-                throw new UnexpectedFlowDirection($direction);
-                // @codeCoverageIgnoreEnd
-        }
+        return match ($direction->value) {
+            FlowDirection::COLUMN => new static(
+                $coordinateSystem->rowForColumnFlowPosition($position),
+                $coordinateSystem->columnForColumnFlowPosition($position),
+                $coordinateSystem
+            ),
+            FlowDirection::ROW => new static(
+                $coordinateSystem->rowForRowFlowPosition($position),
+                $coordinateSystem->columnForRowFlowPosition($position),
+                $coordinateSystem
+            ),
+            default => throw new UnexpectedFlowDirection($direction),
+        };
     }
 
     public function toString(): string
@@ -143,16 +137,11 @@ public function position(FlowDirection $direction): int
         /** @var int<0, max> $columnIndex Must be found, since __construct enforces $this->column is valid */
         $columnIndex = array_search($this->column, $this->coordinateSystem->columns(), true);
 
-        switch ($direction->value) {
-            case FlowDirection::ROW:
-                return $rowIndex * count($this->coordinateSystem->columns()) + $columnIndex + 1;
-            case FlowDirection::COLUMN:
-                return $columnIndex * count($this->coordinateSystem->rows()) + $rowIndex + 1;
-                // @codeCoverageIgnoreStart all Enums are listed and this should never happen
-            default:
-                throw new UnexpectedFlowDirection($direction);
-                // @codeCoverageIgnoreEnd
-        }
+        return match ($direction->value) {
+            FlowDirection::ROW => $rowIndex * count($this->coordinateSystem->columns()) + $columnIndex + 1,
+            FlowDirection::COLUMN => $columnIndex * count($this->coordinateSystem->rows()) + $rowIndex + 1,
+            default => throw new UnexpectedFlowDirection($direction),
+        };
     }
 
     /**
diff --git a/src/Microplate/Enums/FlowDirection.php b/src/Microplate/Enums/FlowDirection.php
index 73d3081..3bf6aa7 100644
--- a/src/Microplate/Enums/FlowDirection.php
+++ b/src/Microplate/Enums/FlowDirection.php
@@ -7,12 +7,9 @@ class FlowDirection
     public const ROW = 'ROW';
     public const COLUMN = 'COLUMN';
 
-    public string $value;
-
-    public function __construct(string $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public string $value
+    ) {}
 
     public static function ROW(): self
     {
diff --git a/src/Microplate/FullColumnSection.php b/src/Microplate/FullColumnSection.php
index 6a87c26..759dfa6 100644
--- a/src/Microplate/FullColumnSection.php
+++ b/src/Microplate/FullColumnSection.php
@@ -66,8 +66,7 @@ private function growSection(): void
         }
     }
 
-    /** @return false|int */
-    private function nextReservedWell()
+    private function nextReservedWell(): int|false
     {
         $search = $this->sectionItems->search(AbstractMicroplate::EMPTY_WELL);
         assert($search === false || is_int($search)); // @phpstan-ignore-line function.alreadyNarrowedType (not yet supported by PHPStan of older versions)
diff --git a/src/Microplate/MicroplateSet/Location.php b/src/Microplate/MicroplateSet/Location.php
index ff28f51..58e4055 100644
--- a/src/Microplate/MicroplateSet/Location.php
+++ b/src/Microplate/MicroplateSet/Location.php
@@ -8,15 +8,9 @@
 /** @template TCoordinateSystem of CoordinateSystem */
 class Location
 {
-    public string $plateID;
-
-    /** @var \MLL\Utils\Microplate\Coordinates<TCoordinateSystem> */
-    public Coordinates $coordinates;
-
     /** @param \MLL\Utils\Microplate\Coordinates<TCoordinateSystem> $coordinates */
-    public function __construct(Coordinates $coordinates, string $plateID)
-    {
-        $this->coordinates = $coordinates;
-        $this->plateID = $plateID;
-    }
+    public function __construct(
+        public Coordinates $coordinates,
+        public string $plateID
+    ) {}
 }
diff --git a/src/Microplate/MicroplateSet/MicroplateSet.php b/src/Microplate/MicroplateSet/MicroplateSet.php
index f00b249..608472d 100644
--- a/src/Microplate/MicroplateSet/MicroplateSet.php
+++ b/src/Microplate/MicroplateSet/MicroplateSet.php
@@ -9,14 +9,10 @@
 /** @template TCoordinateSystem of CoordinateSystem */
 abstract class MicroplateSet
 {
-    /** @var TCoordinateSystem */
-    public CoordinateSystem $coordinateSystem;
-
     /** @param TCoordinateSystem $coordinateSystem */
-    public function __construct(CoordinateSystem $coordinateSystem)
-    {
-        $this->coordinateSystem = $coordinateSystem;
-    }
+    public function __construct(
+        public CoordinateSystem $coordinateSystem
+    ) {}
 
     /** @return list<string> */
     abstract public function plateIDs(): array;
diff --git a/src/Microplate/WellWithCoordinates.php b/src/Microplate/WellWithCoordinates.php
index ba79d0f..525ca04 100644
--- a/src/Microplate/WellWithCoordinates.php
+++ b/src/Microplate/WellWithCoordinates.php
@@ -8,19 +8,12 @@
  */
 class WellWithCoordinates
 {
-    /** @var TWell */
-    public $content;
-
-    /** @var Coordinates<TCoordinateSystem> */
-    public Coordinates $coordinates;
-
     /**
      * @param TWell $content
      * @param Coordinates<TCoordinateSystem> $coordinates
      */
-    public function __construct($content, Coordinates $coordinates)
-    {
-        $this->content = $content;
-        $this->coordinates = $coordinates;
-    }
+    public function __construct(
+        public $content,
+        public Coordinates $coordinates
+    ) {}
 }
diff --git a/src/Number.php b/src/Number.php
index 55a74f0..effa6b0 100644
--- a/src/Number.php
+++ b/src/Number.php
@@ -13,10 +13,8 @@ class Number
      * @param float|int $min
      * @param float|int $max
      * @param float|int $current
-     *
-     * @return float|int
      */
-    public static function clamp($min, $max, $current)
+    public static function clamp($min, $max, $current): float|int
     {
         return max($min, min($max, $current));
     }
diff --git a/src/PHPStan/Rules/NoAssignmentInIfRule.php b/src/PHPStan/Rules/NoAssignmentInIfRule.php
index 039d758..78bc452 100644
--- a/src/PHPStan/Rules/NoAssignmentInIfRule.php
+++ b/src/PHPStan/Rules/NoAssignmentInIfRule.php
@@ -19,7 +19,7 @@
  */
 class NoAssignmentInIfRule implements Rule
 {
-    private NodeFinder $nodeFinder;
+    private readonly NodeFinder $nodeFinder;
 
     public function __construct()
     {
diff --git a/src/PHPStan/Rules/ThrowableClassNameRule.php b/src/PHPStan/Rules/ThrowableClassNameRule.php
index 30c211f..6b01640 100644
--- a/src/PHPStan/Rules/ThrowableClassNameRule.php
+++ b/src/PHPStan/Rules/ThrowableClassNameRule.php
@@ -13,13 +13,9 @@
 /** @implements Rule<Class_> */
 class ThrowableClassNameRule implements Rule
 {
-    private ReflectionProvider $reflectionProvider;
-
     public function __construct(
-        ReflectionProvider $reflectionProvider
-    ) {
-        $this->reflectionProvider = $reflectionProvider;
-    }
+        private readonly ReflectionProvider $reflectionProvider
+    ) {}
 
     public function getNodeType(): string
     {
diff --git a/src/Qiaxcel/QiaxcelImport.php b/src/Qiaxcel/QiaxcelImport.php
index 2bd5cb9..c6260e0 100644
--- a/src/Qiaxcel/QiaxcelImport.php
+++ b/src/Qiaxcel/QiaxcelImport.php
@@ -9,23 +9,12 @@
 
 class QiaxcelImport
 {
-    public string $fileName;
-
-    /** @var list<string> */
-    protected array $entries;
-
-    public string $valueForEmptyCell;
-
     /** @param list<string> $entries */
     public function __construct(
-        string $fileName,
-        array $entries,
-        string $valueForEmptyCell = 'Leer'
-    ) {
-        $this->fileName = $fileName;
-        $this->entries = $entries;
-        $this->valueForEmptyCell = $valueForEmptyCell;
-    }
+        public string $fileName,
+        protected array $entries,
+        public string $valueForEmptyCell = 'Leer'
+    ) {}
 
     public function generate(): SpreadSheet
     {
diff --git a/src/QxManager/FilledRow.php b/src/QxManager/FilledRow.php
index 5ba9b60..1b4aef5 100644
--- a/src/QxManager/FilledRow.php
+++ b/src/QxManager/FilledRow.php
@@ -4,73 +4,24 @@
 
 class FilledRow
 {
-    private string $experimentType;
-
-    private string $supermixName;
-
-    private string $assayType;
-
-    private string $targetType;
-
-    private string $plot;
-
-    private string $targetName;
-
-    private string $signalCh1;
-
-    private string $signalCh2;
-
-    private string $sampleDescription1;
-
-    private ?string $sampleDescription2;
-
-    private ?string $sampleDescription3;
-
-    private ?string $sampleDescription4;
-
-    private string $sampleType;
-
-    private ?int $referenceCopies;
-
-    private ?string $wellNotes;
-
-    private ?string $rdqConversionFactor;
-
     public function __construct(
-        string $sampleDescription1,
-        ?string $sampleDescription2,
-        ?string $sampleDescription3,
-        ?string $sampleDescription4,
-        string $sampleType,
-        string $experimentType,
-        string $supermixName,
-        string $assayType,
-        string $targetType,
-        string $plot,
-        string $targetName,
-        string $signalCh1,
-        string $signalCh2,
-        ?int $referenceCopies = null,
-        ?string $wellNotes = null,
-        ?string $rdqConversionFactor = null
-    ) {
-        $this->targetName = $targetName;
-        $this->signalCh1 = $signalCh1;
-        $this->signalCh2 = $signalCh2;
-        $this->sampleDescription1 = $sampleDescription1;
-        $this->sampleDescription2 = $sampleDescription2;
-        $this->sampleDescription3 = $sampleDescription3;
-        $this->sampleDescription4 = $sampleDescription4;
-        $this->sampleType = $sampleType;
-        $this->experimentType = $experimentType;
-        $this->supermixName = $supermixName;
-        $this->assayType = $assayType;
-        $this->targetType = $targetType;
-        $this->plot = $plot;
-        $this->referenceCopies = $referenceCopies;
-        $this->wellNotes = $wellNotes;
-        $this->rdqConversionFactor = $rdqConversionFactor;
-    }
+        private readonly string $sampleDescription1,
+        private readonly ?string $sampleDescription2,
+        private readonly ?string $sampleDescription3,
+        private readonly ?string $sampleDescription4,
+        private readonly string $sampleType,
+        private readonly string $experimentType,
+        private readonly string $supermixName,
+        private readonly string $assayType,
+        private readonly string $targetType,
+        private readonly string $plot,
+        private readonly string $targetName,
+        private readonly string $signalCh1,
+        private readonly string $signalCh2,
+        private readonly ?int $referenceCopies = null,
+        private readonly ?string $wellNotes = null,
+        private readonly ?string $rdqConversionFactor = null
+    ) {}
 
     public function toString(): string
     {
diff --git a/src/QxManager/FilledWell.php b/src/QxManager/FilledWell.php
index bd4da93..ee3bf67 100644
--- a/src/QxManager/FilledWell.php
+++ b/src/QxManager/FilledWell.php
@@ -7,15 +7,10 @@
 
 class FilledWell
 {
-    private FilledRow $famRow;
-
-    private FilledRow $hexRow;
-
-    public function __construct(FilledRow $famRow, FilledRow $hexRow)
-    {
-        $this->famRow = $famRow;
-        $this->hexRow = $hexRow;
-    }
+    public function __construct(
+        private readonly FilledRow $famRow,
+        private readonly FilledRow $hexRow
+    ) {}
 
     /** @param Coordinates<CoordinateSystem12x8> $coordinates */
     public function toString(Coordinates $coordinates): string
diff --git a/src/Tecan/BasicCommands/AspirateAndDispenseParameters.php b/src/Tecan/BasicCommands/AspirateAndDispenseParameters.php
index a918400..572d74f 100644
--- a/src/Tecan/BasicCommands/AspirateAndDispenseParameters.php
+++ b/src/Tecan/BasicCommands/AspirateAndDispenseParameters.php
@@ -6,18 +6,11 @@
 
 class AspirateAndDispenseParameters
 {
-    private Rack $rack;
-
-    private int $startPosition;
-
-    private int $endPosition;
-
-    public function __construct(Rack $rack, int $startPosition, int $endPosition)
-    {
-        $this->rack = $rack;
-        $this->startPosition = $startPosition;
-        $this->endPosition = $endPosition;
-    }
+    public function __construct(
+        private readonly Rack $rack,
+        private readonly int $startPosition,
+        private readonly int $endPosition
+    ) {}
 
     /** Serializes the aspirate and dispense parameters as part of a reagent distribution according the gwl file format. */
     public function toString(): string
diff --git a/src/Tecan/BasicCommands/Comment.php b/src/Tecan/BasicCommands/Comment.php
index 9d8f3b9..adebcc2 100644
--- a/src/Tecan/BasicCommands/Comment.php
+++ b/src/Tecan/BasicCommands/Comment.php
@@ -4,12 +4,9 @@
 
 class Comment extends Command
 {
-    private string $comment;
-
-    public function __construct(string $comment)
-    {
-        $this->comment = $comment;
-    }
+    public function __construct(
+        private readonly string $comment
+    ) {}
 
     public function toString(): string
     {
diff --git a/src/Tecan/BasicCommands/ReagentDistribution.php b/src/Tecan/BasicCommands/ReagentDistribution.php
index 38ff826..beeb2fb 100644
--- a/src/Tecan/BasicCommands/ReagentDistribution.php
+++ b/src/Tecan/BasicCommands/ReagentDistribution.php
@@ -7,22 +7,7 @@
 
 class ReagentDistribution extends Command
 {
-    private AspirateAndDispenseParameters $source;
-
-    private AspirateAndDispenseParameters $target;
-
-    private float $volume;
-
-    private LiquidClass $liquidClass;
-
-    private ?int $numberOfDitiReuses;
-
-    private ?int $numberOfMultiDisp;
-
-    private ReagentDistributionDirection $direction;
-
-    /** @var array<int>|null */
-    private ?array $excludedTargetWells;
+    private readonly ReagentDistributionDirection $direction;
 
     /**
      * @param int|null $numberOfDitiReuses optional maximum number of DiTi reuses allowed (default 1 = no DiTi reuse)
@@ -31,23 +16,16 @@ class ReagentDistribution extends Command
      * @param array<int>|null $excludedTargetWells Optional list of wells in destination labware to be excluded from pipetting
      */
     public function __construct(
-        AspirateAndDispenseParameters $source,
-        AspirateAndDispenseParameters $target,
-        float $dispenseVolume,
-        LiquidClass $liquidClass,
-        ?int $numberOfDitiReuses = null,
-        ?int $numberOfMultiDisp = null,
+        private readonly AspirateAndDispenseParameters $source,
+        private readonly AspirateAndDispenseParameters $target,
+        private readonly float $volume,
+        private readonly LiquidClass $liquidClass,
+        private readonly ?int $numberOfDitiReuses = null,
+        private readonly ?int $numberOfMultiDisp = null,
         ?ReagentDistributionDirection $direction = null,
-        ?array $excludedTargetWells = null
+        private readonly ?array $excludedTargetWells = null
     ) {
-        $this->source = $source;
-        $this->target = $target;
-        $this->volume = $dispenseVolume;
-        $this->liquidClass = $liquidClass;
-        $this->numberOfDitiReuses = $numberOfDitiReuses;
-        $this->numberOfMultiDisp = $numberOfMultiDisp;
         $this->direction = $direction ?? ReagentDistributionDirection::LEFT_TO_RIGHT();
-        $this->excludedTargetWells = $excludedTargetWells;
     }
 
     public function toString(): string
diff --git a/src/Tecan/BasicCommands/SetDiTiType.php b/src/Tecan/BasicCommands/SetDiTiType.php
index ca0ccdb..094b91b 100644
--- a/src/Tecan/BasicCommands/SetDiTiType.php
+++ b/src/Tecan/BasicCommands/SetDiTiType.php
@@ -9,12 +9,9 @@
  */
 class SetDiTiType extends Command
 {
-    private int $indexOfDiTi;
-
-    public function __construct(int $indexOfDiTi)
-    {
-        $this->indexOfDiTi = $indexOfDiTi;
-    }
+    public function __construct(
+        private readonly int $indexOfDiTi
+    ) {}
 
     public function toString(): string
     {
diff --git a/src/Tecan/CustomCommands/AspirateParameters.php b/src/Tecan/CustomCommands/AspirateParameters.php
index 070b01f..6c1230d 100644
--- a/src/Tecan/CustomCommands/AspirateParameters.php
+++ b/src/Tecan/CustomCommands/AspirateParameters.php
@@ -7,15 +7,10 @@
 
 class AspirateParameters
 {
-    private Rack $rack;
-
-    private int $sourcePosition;
-
-    public function __construct(Rack $rack, int $sourcePosition)
-    {
-        $this->rack = $rack;
-        $this->sourcePosition = $sourcePosition;
-    }
+    public function __construct(
+        private readonly Rack $rack,
+        private readonly int $sourcePosition
+    ) {}
 
     public function formatToAspirateAndDispenseParameters(): AspirateAndDispenseParameters
     {
diff --git a/src/Tecan/CustomCommands/DispenseParameters.php b/src/Tecan/CustomCommands/DispenseParameters.php
index 2dbfd56..8b90d12 100644
--- a/src/Tecan/CustomCommands/DispenseParameters.php
+++ b/src/Tecan/CustomCommands/DispenseParameters.php
@@ -7,17 +7,11 @@
 
 class DispenseParameters
 {
-    public Rack $rack;
-
-    /** @var non-empty-array<int> */
-    public array $dispensePositions;
-
     /** @param non-empty-array<int> $dispensePositions */
-    public function __construct(Rack $rack, array $dispensePositions)
-    {
-        $this->rack = $rack;
-        $this->dispensePositions = $dispensePositions;
-    }
+    public function __construct(
+        public Rack $rack,
+        public array $dispensePositions
+    ) {}
 
     public function formatToAspirateAndDispenseParameters(): AspirateAndDispenseParameters
     {
diff --git a/src/Tecan/CustomCommands/MLLReagentDistribution.php b/src/Tecan/CustomCommands/MLLReagentDistribution.php
index 49c2c4b..e6b7661 100644
--- a/src/Tecan/CustomCommands/MLLReagentDistribution.php
+++ b/src/Tecan/CustomCommands/MLLReagentDistribution.php
@@ -12,25 +12,12 @@ class MLLReagentDistribution extends Command
     public const NUMBER_OF_DITI_REUSES = 6;
     public const NUMBER_OF_MULTI_DISP = 1;
 
-    private AspirateParameters $source;
-
-    private DispenseParameters $target;
-
-    private float $volume;
-
-    private LiquidClass $liquidClass;
-
     public function __construct(
-        AspirateParameters $source,
-        DispenseParameters $target,
-        float $dispenseVolume,
-        LiquidClass $liquidClass
-    ) {
-        $this->source = $source;
-        $this->target = $target;
-        $this->volume = $dispenseVolume;
-        $this->liquidClass = $liquidClass;
-    }
+        private readonly AspirateParameters $source,
+        private readonly DispenseParameters $target,
+        private readonly float $volume,
+        private readonly LiquidClass $liquidClass
+    ) {}
 
     public function toString(): string
     {
diff --git a/src/Tecan/CustomCommands/TransferWithAutoWash.php b/src/Tecan/CustomCommands/TransferWithAutoWash.php
index 8b46b4d..515841d 100644
--- a/src/Tecan/CustomCommands/TransferWithAutoWash.php
+++ b/src/Tecan/CustomCommands/TransferWithAutoWash.php
@@ -13,9 +13,9 @@
 
 class TransferWithAutoWash extends Command implements UsesTipMask
 {
-    private Aspirate $aspirate;
+    private readonly Aspirate $aspirate;
 
-    private Dispense $dispense;
+    private readonly Dispense $dispense;
 
     public function __construct(float $volume, LiquidClass $liquidClass, Location $aspirateLocation, Location $dispenseLocation)
     {
diff --git a/src/Tecan/LiquidClass/CustomLiquidClass.php b/src/Tecan/LiquidClass/CustomLiquidClass.php
index 336f17e..365f88c 100644
--- a/src/Tecan/LiquidClass/CustomLiquidClass.php
+++ b/src/Tecan/LiquidClass/CustomLiquidClass.php
@@ -4,12 +4,9 @@
 
 class CustomLiquidClass implements LiquidClass
 {
-    private string $name;
-
-    public function __construct(string $name)
-    {
-        $this->name = $name;
-    }
+    public function __construct(
+        private readonly string $name
+    ) {}
 
     public function name(): string
     {
diff --git a/src/Tecan/LiquidClass/MLLLiquidClass.php b/src/Tecan/LiquidClass/MLLLiquidClass.php
index 3ddd39d..3fd0264 100644
--- a/src/Tecan/LiquidClass/MLLLiquidClass.php
+++ b/src/Tecan/LiquidClass/MLLLiquidClass.php
@@ -8,14 +8,11 @@ class MLLLiquidClass implements LiquidClass
     public const DNA_DILUTION_WATER = 'DNA_Dilution_Water';
     public const TRANSFER_PCR_PRODUKT = 'Transfer_PCR_Produkt';
     public const TRANSFER_MASTERMIX_MP = 'Transfer_Mastermix_MP';
-    public const TRANSFER_TEMPLATE = 'Transfer_Template'; // DNA-templates and BUFFER!
+    public const TRANSFER_TEMPLATE = 'Transfer_Template';
 
-    public string $value;
-
-    public function __construct(string $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public string $value
+    ) {}
 
     public static function DNA_DILUTION(): self
     {
diff --git a/src/Tecan/Location/BarcodeLocation.php b/src/Tecan/Location/BarcodeLocation.php
index 8d1d87d..d77026c 100644
--- a/src/Tecan/Location/BarcodeLocation.php
+++ b/src/Tecan/Location/BarcodeLocation.php
@@ -6,15 +6,10 @@
 
 class BarcodeLocation implements Location
 {
-    private string $barcode;
-
-    private ScannedRack $rack;
-
-    public function __construct(string $barcode, ScannedRack $rack)
-    {
-        $this->barcode = $barcode;
-        $this->rack = $rack;
-    }
+    public function __construct(
+        private readonly string $barcode,
+        private readonly ScannedRack $rack
+    ) {}
 
     public function tubeID(): string
     {
diff --git a/src/Tecan/Location/PositionLocation.php b/src/Tecan/Location/PositionLocation.php
index 25601dc..d86f261 100644
--- a/src/Tecan/Location/PositionLocation.php
+++ b/src/Tecan/Location/PositionLocation.php
@@ -6,15 +6,10 @@
 
 class PositionLocation implements Location
 {
-    private int $position;
-
-    private Rack $rack;
-
-    public function __construct(int $position, Rack $rack)
-    {
-        $this->position = $position;
-        $this->rack = $rack;
-    }
+    public function __construct(
+        private readonly int $position,
+        private readonly Rack $rack
+    ) {}
 
     public function tubeID(): ?string
     {
diff --git a/src/Tecan/Rack/BaseRack.php b/src/Tecan/Rack/BaseRack.php
index 9f0e9e8..ad2ff91 100644
--- a/src/Tecan/Rack/BaseRack.php
+++ b/src/Tecan/Rack/BaseRack.php
@@ -13,11 +13,9 @@ abstract class BaseRack implements Rack
     /** @var Collection<int, TContent|null> */
     public Collection $positions;
 
-    public CoordinateSystem $coordinateSystem;
-
-    public function __construct(CoordinateSystem $coordinateSystem)
-    {
-        $this->coordinateSystem = $coordinateSystem;
+    public function __construct(
+        public CoordinateSystem $coordinateSystem
+    ) {
         /** @phpstan-ignore-next-line types are correct, but phpstan doesn't understand it */
         $this->positions = Collection::times($this->positionCount(), fn () => self::EMPTY_POSITION)
             ->mapWithKeys(fn ($content, int $position): array => [$position + 1 => $content]); /** @phpstan-ignore missingType.parameter (is in template context) */
diff --git a/src/Tecan/ReagentDistribution/ReagentDistributionDirection.php b/src/Tecan/ReagentDistribution/ReagentDistributionDirection.php
index 1c0785f..b61cb1d 100644
--- a/src/Tecan/ReagentDistribution/ReagentDistributionDirection.php
+++ b/src/Tecan/ReagentDistribution/ReagentDistributionDirection.php
@@ -7,12 +7,9 @@ class ReagentDistributionDirection
     public const LEFT_TO_RIGHT = 0;
     public const RIGHT_TO_LEFT = 1;
 
-    public int $value;
-
-    public function __construct(int $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public int $value
+    ) {}
 
     public static function LEFT_TO_RIGHT(): self
     {
diff --git a/src/Tecan/TecanProtocol.php b/src/Tecan/TecanProtocol.php
index 0b5e255..94c0038 100644
--- a/src/Tecan/TecanProtocol.php
+++ b/src/Tecan/TecanProtocol.php
@@ -22,28 +22,22 @@ class TecanProtocol
 
     public const GEMINI_WORKLIST_FILENAME_SUFFIX = '.gwl';
 
-    private TipMask $tipMask;
-
-    private string $protocolName;
+    private readonly string $protocolName;
 
     /** @var Collection<int, Command> */
-    private Collection $commands;
-
-    public ?int $defaultDiTiTypeIndex;
+    private readonly Collection $commands;
 
     public ?int $currentDiTiTypeIndex;
 
     public function __construct(
-        TipMask $tipMask,
+        private readonly TipMask $tipMask,
         ?string $protocolName = null,
         ?string $userName = null,
-        ?int $defaultDiTiTypeIndex = null
+        public ?int $defaultDiTiTypeIndex = null
     ) {
-        $this->tipMask = $tipMask;
         $this->protocolName = $protocolName ?? Str::uuid()->toString();
         $this->commands = $this->buildHeader($userName, $protocolName);
-        $this->defaultDiTiTypeIndex = $defaultDiTiTypeIndex;
-        $this->currentDiTiTypeIndex = $defaultDiTiTypeIndex;
+        $this->currentDiTiTypeIndex = $this->defaultDiTiTypeIndex;
     }
 
     public function addCommand(Command $command): void
diff --git a/src/Tecan/TipMask/TipMask.php b/src/Tecan/TipMask/TipMask.php
index 4924ff5..1a3c31d 100644
--- a/src/Tecan/TipMask/TipMask.php
+++ b/src/Tecan/TipMask/TipMask.php
@@ -9,14 +9,11 @@ class TipMask
     public const FOUR_TIPS = 'FOUR_TIPS';
     public const EIGHT_TIPS = 'EIGHT_TIPS';
 
-    public string $value;
-
     public ?int $currentTip = null;
 
-    public function __construct(string $value)
-    {
-        $this->value = $value;
-    }
+    public function __construct(
+        public string $value
+    ) {}
 
     public static function FOUR_TIPS(): self
     {
@@ -35,14 +32,11 @@ public static function firstTip(): int
 
     public function isLastTip(): bool
     {
-        switch ($this->value) {
-            case self::FOUR_TIPS:
-                return $this->currentTip === 8;
-            case self::EIGHT_TIPS:
-                return $this->currentTip === 128;
-            default:
-                throw new TecanException("isLastTip not defined for {$this->value}.");
-        }
+        return match ($this->value) {
+            self::FOUR_TIPS => $this->currentTip === 8,
+            self::EIGHT_TIPS => $this->currentTip === 128,
+            default => throw new TecanException("isLastTip not defined for {$this->value}."),
+        };
     }
 
     public function nextTip(): int