diff --git a/.github/workflows/grumphp.yaml b/.github/workflows/grumphp.yaml
index 9e5dccf..c691a73 100644
--- a/.github/workflows/grumphp.yaml
+++ b/.github/workflows/grumphp.yaml
@@ -7,7 +7,7 @@ jobs:
         strategy:
             matrix:
                 operating-system: [ubuntu-latest]
-                php-versions: ['8.3', '8.4', '8.5']
+                php-versions: ['8.4', '8.5']
                 composer-options: ['', '--prefer-lowest']
             fail-fast: false
         name: PHP ${{ matrix.php-versions }} @ ${{ matrix.operating-system }} with ${{ matrix.composer-options }}
diff --git a/composer.json b/composer.json
index 486876e..242e8da 100644
--- a/composer.json
+++ b/composer.json
@@ -15,9 +15,16 @@
         }
     ],
     "require": {
-        "php": "~8.3.0 || ~8.4.0 || ~8.5.0",
+        "php": "~8.4.0 || ~8.5.0",
         "ext-json": "*",
-        "php-standard-library/php-standard-library": "^3.1 || ^4.0 || ^5.0 || ^6.0",
+        "php-standard-library/foundation": "^6.1",
+        "php-standard-library/fun": "^6.1",
+        "php-standard-library/hash": "^6.1",
+        "php-standard-library/iter": "^6.1",
+        "php-standard-library/json": "^6.1",
+        "php-standard-library/regex": "^6.1",
+        "php-standard-library/result": "^6.1",
+        "php-standard-library/type": "^6.1",
         "cardinalby/content-disposition": "^1.1",
         "league/uri": "^7.3",
         "php-http/client-common": "^2.7",
diff --git a/psalm.xml b/psalm.xml
index 953123f..25cb856 100644
--- a/psalm.xml
+++ b/psalm.xml
@@ -8,6 +8,7 @@
     findUnusedBaselineEntry="true"
     findUnusedCode="false"
     ensureOverrideAttribute="false"
+    phpVersion="8.4"
 >
     <projectFiles>
         <directory name="src" />