diff --git a/.dependabot/config.yml b/.dependabot/config.yaml
similarity index 100%
rename from .dependabot/config.yml
rename to .dependabot/config.yaml
diff --git a/.editorconfig b/.editorconfig
index 329611ca..3aaad722 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -13,7 +13,7 @@ indent_size = 2
 [*.neon]
 indent_style = tab
 
-[*.yml]
+[*.{yaml,yml}]
 indent_size = 2
 
 [Makefile]
diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 118930c8..729263ef 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -2,7 +2,12 @@
 
 We are using [GitHub Actions](https://github.com/features/actions) as a continuous integration system.
 
-For details, see [`workflows/continuous-integration.yml`](workflows/continuous-integration.yml).
+For details, take a look at the following workflow configuration files:
+
+- [`workflows/integrate.yaml`](workflows/integrate.yaml)
+- [`workflows/prune.yaml`](workflows/prune.yaml)
+- [`workflows/release.yaml`](workflows/release.yaml)
+- [`workflows/renew.yaml`](workflows/renew.yaml)
 
 ## Coding Standards
 
@@ -40,7 +45,7 @@ $ make static-code-analysis
 
 to run a static code analysis.
 
-We are also using the baseline features of [`phpstan/phpstan`(https://medium.com/@ondrejmirtes/phpstans-baseline-feature-lets-you-hold-new-code-to-a-higher-standard-e77d815a5dff) and [`vimeo/psalm`](https://psalm.dev/docs/running_psalm/dealing_with_code_issues/#using-a-baseline-file).
+We are also using the baseline features of [`phpstan/phpstan`](https://medium.com/@ondrejmirtes/phpstans-baseline-feature-lets-you-hold-new-code-to-a-higher-standard-e77d815a5dff) and [`vimeo/psalm`](https://psalm.dev/docs/running_psalm/dealing_with_code_issues/#using-a-baseline-file).
 
 Run
 
diff --git a/.github/settings.yml b/.github/settings.yml
index 51549117..aa3c6671 100644
--- a/.github/settings.yml
+++ b/.github/settings.yml
@@ -28,6 +28,12 @@ branches:
           - "Tests (7.4, highest)"
         strict: false
       restrictions:
+
+        # https://developer.github.com/v3/repos/branches/#parameters-1
+
+        # Note: User, app, and team restrictions are only available for organization-owned repositories.
+        # Set to null to disable when using this configuration for a repository on a personal account.
+
         apps:
           - "dependabot-preview"
         teams: []
@@ -39,35 +45,35 @@ branches:
 
 labels:
   - name: "bug"
-    color: "#ee0701"
+    color: "ee0701"
     description: ""
 
   - name: "dependency"
-    color: "#0366d6"
+    color: "0366d6"
     description: ""
 
   - name: "enhancement"
-    color: "#0e8a16"
+    color: "0e8a16"
     description: ""
 
   - name: "rfc"
-    color: "#f4db3a"
+    color: "f4db3a"
     description: ""
 
   - name: "question"
-    color: "#cc317c"
+    color: "cc317c"
     description: ""
 
   - name: "security"
-    color: "#ee0701"
+    color: "ee0701"
     description: ""
 
   - name: "stale"
-    color: "#eeeeee"
+    color: "eeeeee"
     description: ""
 
   - name: "vendor"
-    color: "#f4db3a"
+    color: "f4db3a"
     description: ""
 
 # https://developer.github.com/v3/repos/#edit
diff --git a/.github/workflows/continuous-integration.yml b/.github/workflows/integrate.yaml
similarity index 71%
rename from .github/workflows/continuous-integration.yml
rename to .github/workflows/integrate.yaml
index db985f43..f8105970 100644
--- a/.github/workflows/continuous-integration.yml
+++ b/.github/workflows/integrate.yaml
@@ -1,9 +1,9 @@
 # https://help.github.com/en/categories/automating-your-workflow-with-github-actions
 
-name: "Continuous Integration"
+name: "Integrate"
 
-on:
-  pull_request:
+on: # yamllint disable-line rule:truthy
+  pull_request: null
   push:
     branches:
       - "master"
@@ -27,10 +27,17 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.0.0"
+        uses: "actions/checkout@v2"
+
+      - name: "Lint YAML files"
+        uses: "ibiqlik/action-yamllint@v1"
+        with:
+          config_file: ".yamllint.yaml"
+          file_or_dir: "."
+          strict: true
 
       - name: "Install PHP with extensions"
-        uses: "shivammathur/setup-php@1.7.3"
+        uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
           extensions: "${{ env.REQUIRED_PHP_EXTENSIONS }}"
@@ -39,22 +46,26 @@ jobs:
       - name: "Validate composer.json and composer.lock"
         run: "composer validate --strict"
 
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
-          path: "~/.composer/cache"
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('**/composer.lock') }}"
           restore-keys: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-"
 
-      - name: "Install lowest dependencies with composer"
+      - name: "Install lowest dependencies from composer.json"
         if: "matrix.dependencies == 'lowest'"
         run: "composer update --no-interaction --no-progress --no-suggest --prefer-lowest"
 
-      - name: "Install locked dependencies with composer"
+      - name: "Install locked dependencies from composer.lock"
         if: "matrix.dependencies == 'locked'"
         run: "composer install --no-interaction --no-progress --no-suggest"
 
-      - name: "Install highest dependencies with composer"
+      - name: "Install highest dependencies from composer.json"
         if: "matrix.dependencies == 'highest'"
         run: "composer update --no-interaction --no-progress --no-suggest"
 
@@ -65,7 +76,7 @@ jobs:
         run: "mkdir -p .build/php-cs-fixer"
 
       - name: "Cache cache directory for friendsofphp/php-cs-fixer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
           path: ".build/php-cs-fixer"
           key: "php-${{ matrix.php-version }}-php-cs-fixer-${{ hashFiles('**/composer.lock') }}"
@@ -89,36 +100,40 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.0.0"
+        uses: "actions/checkout@v2"
 
       - name: "Install PHP with extensions"
-        uses: "shivammathur/setup-php@1.7.3"
+        uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
           extensions: "${{ env.REQUIRED_PHP_EXTENSIONS }}"
           php-version: "${{ matrix.php-version }}"
 
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
-          path: "~/.composer/cache"
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('**/composer.lock') }}"
           restore-keys: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-"
 
-      - name: "Install lowest dependencies with composer"
+      - name: "Install lowest dependencies from composer.json"
         if: "matrix.dependencies == 'lowest'"
         run: "composer update --no-interaction --no-progress --no-suggest --prefer-lowest"
 
-      - name: "Install locked dependencies with composer"
+      - name: "Install locked dependencies from composer.lock"
         if: "matrix.dependencies == 'locked'"
         run: "composer install --no-interaction --no-progress --no-suggest"
 
-      - name: "Install highest dependencies with composer"
+      - name: "Install highest dependencies from composer.json"
         if: "matrix.dependencies == 'highest'"
         run: "composer update --no-interaction --no-progress --no-suggest"
 
       - name: "Run maglnet/composer-require-checker"
-        uses: "docker://webfactory/composer-require-checker:2.0.0"
+        uses: "docker://webfactory/composer-require-checker:2.1.0"
 
   static-code-analysis:
     name: "Static Code Analysis"
@@ -135,37 +150,48 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.0.0"
+        uses: "actions/checkout@v2"
 
       - name: "Install PHP with extensions"
-        uses: "shivammathur/setup-php@1.7.3"
+        uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
           extensions: "${{ env.REQUIRED_PHP_EXTENSIONS }}"
           php-version: "${{ matrix.php-version }}"
 
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
-          path: "~/.composer/cache"
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
           key: "${{ matrix.php-version }}-composer-locked-${{ hashFiles('**/composer.lock') }}"
           restore-keys: "${{ matrix.php-version }}-composer-locked-"
 
-      - name: "Install lowest dependencies with composer"
+      - name: "Install lowest dependencies from composer.json"
         if: "matrix.dependencies == 'lowest'"
         run: "composer update --no-interaction --no-progress --no-suggest --prefer-lowest"
 
-      - name: "Install locked dependencies with composer"
+      - name: "Install locked dependencies from composer.lock"
         if: "matrix.dependencies == 'locked'"
         run: "composer install --no-interaction --no-progress --no-suggest"
 
-      - name: "Install highest dependencies with composer"
+      - name: "Install highest dependencies from composer.json"
         if: "matrix.dependencies == 'highest'"
         run: "composer update --no-interaction --no-progress --no-suggest"
 
       - name: "Create cache directory for phpstan/phpstan"
         run: "mkdir -p .build/phpstan"
 
+      - name: "Cache cache directory for phpstan/phpstan"
+        uses: "actions/cache@v1"
+        with:
+          path: ".build/phpstan"
+          key: "php-${{ matrix.php-version }}-phpstan-${{ hashFiles('**/composer.lock') }}"
+          restore-keys: "php-${{ matrix.php-version }}-phpstan-"
+
       - name: "Run phpstan/phpstan"
         run: "vendor/bin/phpstan analyse --configuration=phpstan.neon"
 
@@ -194,31 +220,35 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.0.0"
+        uses: "actions/checkout@v2"
 
       - name: "Install PHP with extensions"
-        uses: "shivammathur/setup-php@1.7.3"
+        uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
           extensions: "${{ env.REQUIRED_PHP_EXTENSIONS }}"
           php-version: "${{ matrix.php-version }}"
 
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
-          path: "~/.composer/cache"
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('**/composer.lock') }}"
           restore-keys: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-"
 
-      - name: "Install lowest dependencies with composer"
+      - name: "Install lowest dependencies from composer.json"
         if: "matrix.dependencies == 'lowest'"
         run: "composer update --no-interaction --no-progress --no-suggest --prefer-lowest"
 
-      - name: "Install locked dependencies with composer"
+      - name: "Install locked dependencies from composer.lock"
         if: "matrix.dependencies == 'locked'"
         run: "composer install --no-interaction --no-progress --no-suggest"
 
-      - name: "Install highest dependencies with composer"
+      - name: "Install highest dependencies from composer.json"
         if: "matrix.dependencies == 'highest'"
         run: "composer update --no-interaction --no-progress --no-suggest"
 
diff --git a/.github/workflows/prune.yaml b/.github/workflows/prune.yaml
new file mode 100644
index 00000000..449e4652
--- /dev/null
+++ b/.github/workflows/prune.yaml
@@ -0,0 +1,31 @@
+# https://github.com/actions/stale
+
+name: "Prune"
+
+on: # yamllint disable-line rule:truthy
+  schedule:
+    - cron: "0 12 * * *"
+
+jobs:
+  prune:
+    name: "Issues"
+
+    runs-on: "ubuntu-latest"
+
+    steps:
+      - name: "Prune issues and pull requests"
+        uses: "actions/stale@v1"
+        with:
+          days-before-close: 5
+          days-before-stale: 60
+          repo-token: "${{ secrets.ERGEBNIS_BOT_TOKEN }}"
+          stale-issue-label: "stale"
+          stale-issue-message: |
+            Since this issue has not had any activity within the last sixty days, I have marked it as stale.
+
+            I will close it if no further activity occurs within the next five days.
+          stale-pr-label: "stale"
+          stale-pr-message: |
+            Since this pull request has not had any activity within the last sixty days, I have marked it as stale.
+
+            I will close it if no further activity occurs within the next five days.
diff --git a/.github/workflows/continuous-deployment.yml b/.github/workflows/release.yaml
similarity index 86%
rename from .github/workflows/continuous-deployment.yml
rename to .github/workflows/release.yaml
index c8b2a2e9..5cd6d94b 100644
--- a/.github/workflows/continuous-deployment.yml
+++ b/.github/workflows/release.yaml
@@ -1,8 +1,8 @@
 # https://help.github.com/en/categories/automating-your-workflow-with-github-actions
 
-name: "Continuous Deployment"
+name: "Release"
 
-on:
+on: # yamllint disable-line rule:truthy
   push:
     tags:
       - "**"
@@ -19,7 +19,7 @@ jobs:
         run: "echo \"::set-output name=tag::${GITHUB_REF#refs/tags/}\""
 
       - name: "Create release"
-        uses: "actions/create-release@v1.0.0"
+        uses: "actions/create-release@v1"
         env:
           GITHUB_TOKEN: "${{ secrets.ERGEBNIS_BOT_TOKEN }}"
         with:
diff --git a/.github/workflows/license.yml b/.github/workflows/renew.yaml
similarity index 76%
rename from .github/workflows/license.yml
rename to .github/workflows/renew.yaml
index 5786ef26..c6923adf 100644
--- a/.github/workflows/license.yml
+++ b/.github/workflows/renew.yaml
@@ -1,8 +1,8 @@
 # https://help.github.com/en/categories/automating-your-workflow-with-github-actions
 
-name: "License"
+name: "Renew"
 
-on:
+on: # yamllint disable-line rule:truthy
   schedule:
     - cron: "1 0 1 1 *"
 
@@ -18,17 +18,17 @@ jobs:
     strategy:
       matrix:
         php-version:
-          - "7.1"
+          - "7.2"
 
         dependencies:
           - "locked"
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.0.0"
+        uses: "actions/checkout@v2"
 
       - name: "Install PHP with extensions"
-        uses: "shivammathur/setup-php@1.7.3"
+        uses: "shivammathur/setup-php@v2"
         with:
           coverage: "none"
           extensions: "${{ env.REQUIRED_PHP_EXTENSIONS }}"
@@ -37,22 +37,26 @@ jobs:
       - name: "Validate composer.json and composer.lock"
         run: "composer validate --strict"
 
+      - name: "Determine composer cache directory"
+        id: "determine-composer-cache-directory"
+        run: "echo \"::set-output name=directory::$(composer config cache-dir)\""
+
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
-          path: "~/.composer/cache"
+          path: "${{ steps.determine-composer-cache-directory.outputs.directory }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('**/composer.lock') }}"
           restore-keys: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-"
 
-      - name: "Install lowest dependencies with composer"
+      - name: "Install lowest dependencies from composer.json"
         if: "matrix.dependencies == 'lowest'"
         run: "composer update --no-interaction --no-progress --no-suggest --prefer-lowest"
 
-      - name: "Install locked dependencies with composer"
+      - name: "Install locked dependencies from composer.lock"
         if: "matrix.dependencies == 'locked'"
         run: "composer install --no-interaction --no-progress --no-suggest"
 
-      - name: "Install highest dependencies with composer"
+      - name: "Install highest dependencies from composer.json"
         if: "matrix.dependencies == 'highest'"
         run: "composer update --no-interaction --no-progress --no-suggest"
 
@@ -60,7 +64,7 @@ jobs:
         run: "mkdir -p .build/php-cs-fixer"
 
       - name: "Cache cache directory for friendsofphp/php-cs-fixer"
-        uses: "actions/cache@v1.0.3"
+        uses: "actions/cache@v1"
         with:
           path: ".build/php-cs-fixer"
           key: "php-${{ matrix.php-version }}-php-cs-fixer-${{ hashFiles('**/composer.lock') }}"
@@ -70,7 +74,7 @@ jobs:
         run: "vendor/bin/php-cs-fixer fix --config=.php_cs --diff --diff-format=udiff --dry-run --verbose"
 
       - name: "Open pull request updating license year"
-        uses: "gr2m/create-or-update-pull-request-action@v1.2.9"
+        uses: "gr2m/create-or-update-pull-request-action@v1.2.10"
         with:
           author: "ergebnis-bot <bot@ergebn.is>"
           branch: "feature/license-year"
diff --git a/.github/workflows/stale.yml b/.github/workflows/stale.yml
deleted file mode 100644
index 0d6f48ef..00000000
--- a/.github/workflows/stale.yml
+++ /dev/null
@@ -1,29 +0,0 @@
-# https://github.com/actions/stale
-
-name: "Stale"
-
-on:
-  schedule:
-    - cron: "0 12 * * *"
-
-jobs:
-  stale:
-    runs-on: "ubuntu-latest"
-
-    steps:
-      - name: "Close stale issues and pull requests"
-        uses: "actions/stale@v1.1.0"
-        with:
-          days-before-close: 5
-          days-before-stale: 60
-          repo-token: "${{ secrets.ERGEBNIS_BOT_TOKEN }}"
-          stale-issue-label: 'stale'
-          stale-issue-message: >
-            This issue has been automatically marked as stale because it has not had
-            recent activity. It will be closed if no further activity occurs. Thank you
-            for your contributions.
-          stale-pr-label: "stale"
-          stale-pr-message: >
-            This PR has been automatically marked as stale because it has not had
-            recent activity. It will be closed if no further activity occurs. Thank you
-            for your contributions.
diff --git a/.php_cs b/.php_cs
index 0241e668..7846af94 100644
--- a/.php_cs
+++ b/.php_cs
@@ -32,9 +32,9 @@ $config->getFinder()
     ->ignoreDotFiles(false)
     ->in(__DIR__)
     ->exclude([
-        '.build',
-        '.dependabot',
-        '.github',
+        '.build/',
+        '.dependabot/',
+        '.github/',
     ])
     ->name('.php_cs');
 
diff --git a/.yamllint.yaml b/.yamllint.yaml
new file mode 100644
index 00000000..17b1b556
--- /dev/null
+++ b/.yamllint.yaml
@@ -0,0 +1,65 @@
+extends: "default"
+
+ignore: |
+  .build/
+  vendor/
+
+rules:
+  braces:
+    max-spaces-inside-empty: 0
+    max-spaces-inside: 1
+    min-spaces-inside-empty: 0
+    min-spaces-inside: 1
+  brackets:
+    max-spaces-inside-empty: 0
+    max-spaces-inside: 0
+    min-spaces-inside-empty: 0
+    min-spaces-inside: 0
+  colons:
+    max-spaces-after: 1
+    max-spaces-before: 0
+  commas:
+    max-spaces-after: 1
+    max-spaces-before: 0
+    min-spaces-after: 1
+  comments:
+    ignore-shebangs: true
+    min-spaces-from-content: 1
+    require-starting-space: true
+  comments-indentation: "enable"
+  document-end:
+    present: false
+  document-start:
+    present: false
+  indentation:
+    check-multi-line-strings: true
+    indent-sequences: true
+    spaces: 2
+  empty-lines:
+    max-end: 0
+    max-start: 0
+    max: 1
+  empty-values:
+    forbid-in-block-mappings: true
+    forbid-in-flow-mappings: true
+  hyphens:
+    max-spaces-after: 2
+  key-duplicates: "enable"
+  key-ordering: "disable"
+  line-length: "disable"
+  new-line-at-end-of-file: "enable"
+  new-lines:
+    type: "unix"
+  octal-values:
+    forbid-implicit-octal: true
+  quoted-strings:
+    quote-type: "double"
+  trailing-spaces: "enable"
+  truthy:
+    allowed-values:
+      - "false"
+      - "true"
+
+yaml-files:
+  - '*.yaml'
+  - '*.yml'
diff --git a/Makefile b/Makefile
index 3228a3c8..1cb60ad8 100644
--- a/Makefile
+++ b/Makefile
@@ -3,12 +3,13 @@ it: coding-standards dependency-analysis static-code-analysis tests ## Runs the
 
 .PHONY: coding-standards
 coding-standards: vendor ## Fixes code style issues with friendsofphp/php-cs-fixer
+	yamllint -c .yamllint.yaml --strict .
 	mkdir -p .build/php-cs-fixer
 	vendor/bin/php-cs-fixer fix --config=.php_cs --diff --diff-format=udiff --verbose
 
 .PHONY: dependency-analysis
 dependency-analysis: vendor ## Runs a dependency analysis with maglnet/composer-require-checker
-	docker run --interactive --rm --tty --volume ${PWD}:/app webfactory/composer-require-checker:2.0.0
+	docker run --interactive --rm --tty --volume ${PWD}:/app webfactory/composer-require-checker:2.1.0
 
 .PHONY: help
 help: ## Displays this list of targets with descriptions
diff --git a/README.md b/README.md
index 675797e0..db183548 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,9 @@
 # http-method
 
-[![Continuous Deployment](https://github.com/ergebnis/http-method/workflows/Continuous%20Deployment/badge.svg)](https://github.com/ergebnis/http-method/actions)
-[![Continuous Integration](https://github.com/ergebnis/http-method/workflows/Continuous%20Integration/badge.svg)](https://github.com/ergebnis/http-method/actions)
+[![Integrate](https://github.com/ergebnis/http-method/workflows/Integrate/badge.svg?branch=master)](https://github.com/ergebnis/http-method/actions)
+[![Prune](https://github.com/ergebnis/http-method/workflows/Prune/badge.svg?branch=master)](https://github.com/ergebnis/http-method/actions)
+[![Release](https://github.com/ergebnis/http-method/workflows/Release/badge.svg?branch=master)](https://github.com/ergebnis/http-method/actions)
+[![Renew](https://github.com/ergebnis/http-method/workflows/Renew/badge.svg?branch=master)](https://github.com/ergebnis/http-method/actions)
 
 [![Type Coverage](https://shepherd.dev/github/ergebnis/http-method/coverage.svg)](https://shepherd.dev/github/ergebnis/http-method)
 
@@ -150,4 +152,6 @@ Please have a look at [`CODE_OF_CONDUCT.md`](https://github.com/ergebnis/.github
 
 ## License
 
-This package is licensed using the [MIT License](LICENSE.md).
+This package is licensed using the MIT License.
+
+Please have a look at [`LICENSE.md`](LICENSE.md).
diff --git a/phpstan.neon b/phpstan.neon
index d52be24d..c1075f0a 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -6,6 +6,6 @@ parameters:
 	inferPrivatePropertyTypeFromConstructor: true
 	level: max
 	paths:
-		- src
-		- test
-	tmpDir: %currentWorkingDirectory%/.build/phpstan
+		- src/
+		- test/
+	tmpDir: %currentWorkingDirectory%/.build/phpstan/
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 9ba07fe4..4380f5a9 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<files psalm-version="3.8.1@8e54e3aa060fc490d86d0e2abbf62750516d40fd">
+<files psalm-version="3.9.5@0cfe565d0afbcd31eadcc281b9017b5692911661">
   <file src="test/Unit/Method/Rfc/Rfc3648Test.php">
     <RedundantCondition occurrences="1">
       <code>assertSame</code>
@@ -77,4 +77,14 @@
       <code>assertSame</code>
     </RedundantCondition>
   </file>
+  <file src="test/Unit/Method/WebDavTest.php">
+    <MixedInferredReturnType occurrences="1">
+      <code>array</code>
+    </MixedInferredReturnType>
+  </file>
+  <file src="test/Unit/MethodTest.php">
+    <MixedInferredReturnType occurrences="1">
+      <code>array</code>
+    </MixedInferredReturnType>
+  </file>
 </files>
diff --git a/psalm.xml b/psalm.xml
index 87dbffbd..d645df4b 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -3,7 +3,9 @@
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns="https://getpsalm.org/schema/config"
     xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+    cacheDirectory=".build/psalm"
     errorBaseline="psalm-baseline.xml"
+    errorLevel="1"
     resolveFromConfigFile="true"
 >
     <issueHandlers>
@@ -15,10 +17,10 @@
     </plugins>
 
     <projectFiles>
-        <directory name="src" />
-        <directory name="test" />
+        <directory name="src/" />
+        <directory name="test/" />
         <ignoreFiles>
-            <directory name="vendor" />
+            <directory name="vendor/" />
         </ignoreFiles>
     </projectFiles>
 </psalm>
diff --git a/test/Unit/phpunit.xml b/test/Unit/phpunit.xml
index 07b9c636..5d606146 100644
--- a/test/Unit/phpunit.xml
+++ b/test/Unit/phpunit.xml
@@ -29,7 +29,7 @@
     </testsuites>
     <filter>
         <whitelist addUncoveredFilesFromWhitelist="true" processUncoveredFilesFromWhitelist="true">
-            <directory suffix=".php">../../src</directory>
+            <directory suffix=".php">../../src/</directory>
         </whitelist>
     </filter>
 </phpunit>