diff --git a/.github/workflows/qa.yml b/.github/workflows/qa.yml
index f6c2d2a..5efb0e0 100644
--- a/.github/workflows/qa.yml
+++ b/.github/workflows/qa.yml
@@ -1,31 +1,50 @@
 name: PHP Quality Assurance
-on: [push]
+on: [push, pull_request]
 jobs:
-    build:
+    tests:
         runs-on: ubuntu-latest
         if: "!contains(github.event.head_commit.message, 'ci skip')"
         strategy:
+            fail-fast: true
             matrix:
-                php-versions: ['7.1', '7.2', '7.3', '7.4']
+                php-versions: ['7.1', '7.2', '7.3', '7.4', '8.0']
         steps:
-            -   uses: actions/checkout@v2
+            - uses: actions/checkout@v2
+
+            - name: Setup PHP
+              uses: shivammathur/setup-php@v2
+              with:
+                  php-version: ${{ matrix.php-versions }}
+
+            - name: Check syntax error in sources
+              run: find ./src/ ./tests/ -type f -name '*.php' -print0 | xargs -0 -L 1 -P 4 -- php -l
+
+            - name: Install dependencies
+              uses: "ramsey/composer-install@v1"
+
+            - name: Run unit tests
+              run: composer tests:no-cov
+
+    static:
+        runs-on: ubuntu-latest
+        if: "!contains(github.event.head_commit.message, 'ci skip')"
+        steps:
+            -   name: Checkout
+                uses: actions/checkout@v2
 
             -   name: Setup PHP
                 uses: shivammathur/setup-php@v2
                 with:
-                    php-version: ${{ matrix.php-versions }}
-
-            -   name: Check syntax error in sources
-                run: find ./src/ ./tests/ -type f -name '*.php' -print0 | xargs -0 -L 1 -P 4 -- php -l
+                    php-version: 7.4
 
             -   name: Install dependencies
-                run: composer install -q -n -a --no-progress --prefer-dist
-
-            -   name: Run unit tests
-                run: ./vendor/bin/phpunit --no-coverage
+                uses: "ramsey/composer-install@v1"
 
             -   name: Check code styles
-                run: ./vendor/bin/phpcs
+                run: composer cs
 
             -   name: Check Psalm
-                run: ./vendor/bin/psalm --show-info=false --no-progress --output-format=compact
+                run: composer psalm
+
+            -   name: Check cross-version PHP compatibility
+                run: composer phpcompat
diff --git a/composer.json b/composer.json
index 235d169..1667e23 100644
--- a/composer.json
+++ b/composer.json
@@ -44,8 +44,10 @@
         "psalm": "@php ./vendor/vimeo/psalm/psalm",
         "tests": "@php ./vendor/phpunit/phpunit/phpunit",
         "tests:no-cov": "@php ./vendor/phpunit/phpunit/phpunit --no-coverage",
+        "phpcompat": "@php ./vendor/squizlabs/php_codesniffer/bin/phpcs -p . --standard=PHPCompatibility --ignore=*/vendor/* --extensions=php --basepath=./ --runtime-set testVersion 7.1-",
         "qa": [
             "@cs",
+            "@phpcompat",
             "@psalm",
             "@tests:no-cov"
         ]
diff --git a/psalm.xml b/psalm.xml
index 7f763a8..fb1ed5c 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -2,23 +2,12 @@
 <psalm
     autoloader="./.psalm/autoloader.php"
     totallyTyped="true"
-    useDocblockTypes="true"
     useDocblockPropertyTypes="true"
     usePhpDocMethodsWithoutMagicCall="true"
     strictBinaryOperands="true"
-    requireVoidReturnType="true"
-    useAssertForType="true"
-    rememberPropertyAssignmentsAfterCall="true"
-    allowPhpStormGenerics="true"
-    allowStringToStandInForClass="false"
-    memoizeMethodCallResults="false"
-    hoistConstants="false"
-    addParamDefaultToDocblockType="false"
-    checkForThrowsInGlobalScope="false"
     ignoreInternalFunctionFalseReturn="false"
     ignoreInternalFunctionNullReturn="false"
     hideExternalErrors="true"
-    allowFileIncludes="true"
     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"