diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 06ada0e..a311e64 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, macOS-latest]
-        php-version: ['8.2', '8.3']
+        php-version: ['8.2', '8.3', '8.4']
         dependency-versions: ['lowest', 'highest']
     name: 'PHPUnit'
     steps:
@@ -30,43 +30,8 @@ jobs:
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
   psalm:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        php-version: ['8.2', '8.3']
-        dependency-versions: ['lowest', 'highest']
-    name: 'Psalm'
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-      - name: Setup PHP
-        uses: shivammathur/setup-php@v2
-        with:
-          php-version: ${{ matrix.php-version }}
-          extensions: mbstring, intl
-          coverage: none
-      - name: Composer
-        uses: "ramsey/composer-install@v2"
-        with:
-          dependency-versions: ${{ matrix.dependencies }}
-      - name: Psalm
-        run: vendor/bin/psalm --shepherd
+    uses: innmind/github-workflows/.github/workflows/psalm-matrix.yml@main
   cs:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        php-version: ['8.2']
-    name: 'CS'
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-      - name: Setup PHP
-        uses: shivammathur/setup-php@v2
-        with:
-          php-version: ${{ matrix.php-version }}
-          extensions: mbstring, intl
-          coverage: none
-      - name: Composer
-        uses: "ramsey/composer-install@v2"
-      - name: CS
-        run: vendor/bin/php-cs-fixer fix --diff --dry-run
+    uses: innmind/github-workflows/.github/workflows/cs.yml@main
+    with:
+      php-version: '8.2'
diff --git a/composer.json b/composer.json
index 733dfb7..d821dfa 100644
--- a/composer.json
+++ b/composer.json
@@ -31,7 +31,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "~10.0",
-        "vimeo/psalm": "~5.23",
+        "vimeo/psalm": "~5.23|dev-master",
         "innmind/coding-standard": "~2.0"
     }
 }
diff --git a/src/Json.php b/src/Json.php
index 2f2d27f..7976490 100644
--- a/src/Json.php
+++ b/src/Json.php
@@ -67,11 +67,20 @@ public static function maybeDecode(string $string): Maybe
     public static function encode(mixed $content, int $options = 0, int $depth = 512): string
     {
         try {
-            return \json_encode(
+            $content = \json_encode(
                 $content,
                 $options | \JSON_THROW_ON_ERROR,
                 $depth,
             );
+
+            if ($content === false) {
+                // This case should not happen since we use the option to throw
+                // on error. But Psalm doesn't understand that so we have to
+                // handle the `false` case.
+                throw new \JsonException;
+            }
+
+            return $content;
         } catch (\JsonException $e) {
             throw self::wrap($e);
         }