diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 642d8ea..8ed6e34 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,9 +8,8 @@ jobs:
     runs-on: ${{ matrix.operating-system }}
     strategy:
       matrix:
-        operating-system: ['ubuntu-16.04']
+        operating-system: ['ubuntu-18.04']
         php-versions: ['5.3', '5.4', '5.5', '5.6', '7.0']
-        phpunit-versions: ['7.5.20']
     steps:
       - name: Checkout
         uses: actions/checkout@v2
@@ -20,57 +19,28 @@ jobs:
         with:
           php-version: ${{ matrix.php-versions }}
           extensions: mbstring, intl
-          ini-values: post_max_size=256M, max_execution_time=180
-          tools: psalm, phpunit:${{ matrix.phpunit-versions }}
+          ini-values: error_reporting=-1, display_errors=On
+          coverage: none
 
-      - name: Install dependencies
-        run: composer self-update --1; composer install
+      - name: Use Composer 1.x
+        run: composer self-update --1
+
+      - name: Install Composer dependencies
+        uses: "ramsey/composer-install@v1"
 
       - name: PHPUnit tests
-        uses: php-actions/phpunit@v2
-        with:
-          memory_limit: 256M
+        run: vendor/bin/phpunit
 
-  moderate:
+  moderate-modern:
     name: PHP ${{ matrix.php-versions }} Test on ${{ matrix.operating-system }}
     runs-on: ${{ matrix.operating-system }}
     strategy:
       matrix:
         operating-system: ['ubuntu-latest']
-        php-versions: ['7.1', '7.2', '7.3']
-        phpunit-versions: ['latest']
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v2
-
-      - name: Setup PHP
-        uses: shivammathur/setup-php@v2
-        with:
-          php-version: ${{ matrix.php-versions }}
-          extensions: mbstring, intl, sodium
-          ini-values: post_max_size=256M, max_execution_time=180
-          tools: psalm, phpunit:${{ matrix.phpunit-versions }}
-
-      - name: Install dependencies
-        run: composer install
-
-      - name: Modernize dependencies
-        run: composer require --dev "phpunit/phpunit:>=4"
+        php-versions: ['7.1', '7.2', '7.3', '7.4', '8.0', '8.1']
 
-      - name: PHPUnit tests
-        uses: php-actions/phpunit@v2
-        timeout-minutes: 30
-        with:
-          memory_limit: 256M
+    continue-on-error: ${{ matrix.php-versions == '8.1' }}
 
-  modern:
-    name: PHP ${{ matrix.php-versions }} Test on ${{ matrix.operating-system }}
-    runs-on: ${{ matrix.operating-system }}
-    strategy:
-      matrix:
-        operating-system: ['ubuntu-latest']
-        php-versions: ['7.4', '8.0']
-        phpunit-versions: ['latest']
     steps:
       - name: Checkout
         uses: actions/checkout@v2
@@ -80,23 +50,21 @@ jobs:
         with:
           php-version: ${{ matrix.php-versions }}
           extensions: mbstring, intl, sodium
-          ini-values: post_max_size=256M, max_execution_time=180
-          tools: psalm, phpunit:${{ matrix.phpunit-versions }}
-
-      - name: Install dependencies
-        run: composer install
+          ini-values: error_reporting=-1, display_errors=On
+          coverage: none
 
       - name: Modernize dependencies
-        run: composer require --dev "phpunit/phpunit:>=4"
+        run: composer require --dev --no-update "phpunit/phpunit:>=4"
 
-      - name: PHPUnit tests
-        uses: php-actions/phpunit@v2
-        timeout-minutes: 30
-        with:
-          memory_limit: 256M
+      - name: Install Composer dependencies (PHP < 8.1)
+        if: ${{ matrix.php-versions != '8.1' }}
+        uses: "ramsey/composer-install@v1"
 
-      - name: Install Psalm
-        run: rm composer.lock && composer require --dev vimeo/psalm:^4
+      - name: Install Composer dependencies - ignore-platform-reqs (PHP 8.1)
+        if: ${{ matrix.php-versions == '8.1' }}
+        uses: "ramsey/composer-install@v1"
+        with:
+          composer-options: --ignore-platform-reqs
 
-      - name: Static Analysis
-        run: vendor/bin/psalm
+      - name: PHPUnit tests
+        run: vendor/bin/phpunit
diff --git a/.github/workflows/psalm.yml b/.github/workflows/psalm.yml
new file mode 100644
index 0000000..43aeeea
--- /dev/null
+++ b/.github/workflows/psalm.yml
@@ -0,0 +1,30 @@
+name: Psalm
+
+on: [push]
+
+jobs:
+  psalm:
+    name: Psalm on PHP ${{ matrix.php-versions }}
+    runs-on: ${{ matrix.operating-system }}
+    strategy:
+      matrix:
+        operating-system: ['ubuntu-latest']
+        php-versions: ['7.4']
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-versions }}
+          tools: psalm:4
+          coverage: none
+
+      - name: Install Composer dependencies
+        uses: "ramsey/composer-install@v1"
+        with:
+          composer-options: --no-dev
+
+      - name: Static Analysis
+        run: psalm